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Architecting a secure landing zone in the AWS European Sovereign Cloud

16 September 2026 at 23:20

The AWS European Sovereign Cloud is a new, independent cloud for Europe, physically and logically separate from existing AWS Regions and operated within the European Union (EU). It provides the same services, features, and APIs as AWS commercial Regions, but runs as a distinct AWS partition (aws-eusc), with its own control plane, AWS Identity and Access Management (IAM), billing, console, and service endpoints. Understanding the partition boundary is the key that unlocks correct answers to questions about billing roll-ups, single sign-on (SSO), cross-account roles, AWS Direct Connect, and image distribution. In this post, we show you how to architect a secure, scalable landing zone in the AWS European Sovereign Cloud. We cover account structure and governance, identity managed as infrastructure as code (IaC), centralized logging to a security and event management (SIEM) tool, data protection, network and perimeter design, secure continuous integration and delivery (CI/CD) and artifact distribution, and incident response. Throughout, we map the design to the AWS Security Reference Architecture (AWS SRA) and the AWS Well-Architected Framework, and we call out which behaviors are platform boundaries of a sovereign partition and which are configuration choices you can adapt.

If you are evaluating compliance readiness alongside your landing zone build-out, see the companion post Landing Zone Accelerator Independent Assessment Report for C5:2020 now available on AWS Artifact. This post covers how to align with C5:2020 criteria and provides an independent assessment report and compliance workbook, resources that complement the architectural patterns described here.

The foundational concept: EUSC is a partition

AWS groups Regions into partitions. Every Region is in exactly one partition, and each partition has one or more Regions. Partitions have independent instances of AWS Identity and Access Management (IAM) and provide a hard boundary between Regions in different partitions. AWS commercial Regions are in the aws partition, Regions in China are in the aws-cn partition, and AWS GovCloud Regions are in the aws-us-gov partition. The AWS European Sovereign Cloud is the aws-eusc partition, with its first Region in Brandenburg, Germany (eusc-de-east-1).

Some AWS services provide cross-Region functionality, such as Amazon S3 Cross-Region Replication or AWS Transit Gateway Inter-Region peering. These capabilities work only between Regions in the same partition. You can’t use IAM credentials from one partition to interact with resources in a different partition. There are practical differences that impact your architecture, shown in the following table:

Dimension Commercial AWS (aws) AWS European Sovereign Cloud (aws-eusc)
ARN prefix arn:aws: arn:aws-eusc:
Console or endpoint domain amazonaws.com amazonaws.eu
AWS Organizations One organization in the partition A separate, independent organization
AWS IAM Identity Center Instance in the partition A separate instance in the partition
Billing Consolidated in the partition’s payer A separate payer and billing system (EUR currency)
Cross-partition features and services such as: sts:AssumeRole, VPC peering, Transit Gateway, AWS RAM, Amazon S3 replication Cross-Region features and functionality Not available across the aws and aws-eusc boundary

Every AWS Region is sovereign by design: if you find yourself architecting across Regions, note that this partition boundary means that the centralization—one organization, one logging account, one identity source, one billing roll-up—is achievable within each partition. In the EUSC you operate an independent landing zone in aws-eusc that mirrors your commercial operating model. Where you need to bridge the two clouds (for example, a standard application CI/CD system in an AWS commercial Region deploying into EUSC), you integrate at the network or API layer with separate credentials for each partition, not with cross-partition trust. With these partition fundamentals in mind, the remainder of this post walks you through the considerations to build a production-ready landing zone in the EUSC. Each section addresses a critical layer of the architecture, starting with how to write partition-aware infrastructure code that works across both aws and aws-eusc, then moving into the organizational and governance controls that underpin everything else.

Cross-partition IaC

These Terraform and AWS CloudFormation IaC snippets demonstrate partition-aware Amazon Resource Name (ARN) construction—a pattern that helps ensure your infrastructure code works unchanged across AWS partitions (such as standard aws, GovCloud aws-us-gov, or European Sovereign Cloud aws-eusc).

In the case of using the same Terraform script from a commercial Region, ensure that arn:aws isn’t hard coded. This Terraform script derives the partition at deploy time so the same modules work in both AWS commercial Regions and the EUSC.

# Terraform: partition-aware ARNs (works unchanged in aws and aws-eusc)data "aws_partition""current" {}
data "aws_partition" "current" {}
data "aws_region" "current" {}
data "aws_caller_identity" "current" {}
data "aws_organizations_organization" "current" {}

locals {
partition = data.aws_partition.current.partition# "aws" or "aws-eusc"
account_id = data.aws_caller_identity.current.account_id
org_id= data.aws_organizations_organization.current.id
ecs_task_execution_policy_arn = "arn:${local.partition}:iam::aws:policy/service-role/AmazonECSTaskExecutionRolePolicy"
central_logs_bucket_arn= "arn:${local.partition}:s3:::${local.org_id}-central-logs"
}

resource "aws_iam_role" "amazon_ecs_role" {
  name = "AmazonECSrole"
  assume_role_policy = jsonencode({
    Version = "2012-10-17"
    Statement = [
      {
        Action = "sts:AssumeRole"
        Effect = "Allow"
        Sid= ""
        Principal = {
          # IAM service principals are "amazonaws.com" across all partitions,
          # this stays literal (do NOT use ${AWS::URLSuffix} here).
          Service = "ecs-tasks.amazonaws.com"
        }
      },
    ]
  })
}

resource "aws_iam_role_policy_attachment" "amazon_ecs_role_attach" {
  role= "AmazonECSrole"
  # Use ${local.partition } rather than hardcoding "aws" in the ARN.
  policy_arn = "arn:${local.partition}:iam::aws:policy/service-role/AmazonECSTaskExecutionRolePolicy"
}
# CloudFormation: use the AWS::Partition pseudo parameter, never a literal "aws"

AWSTemplateFormatVersion: "2010-09-09"

Description: >-
Creates an ECS task execution role. Demonstrates using the
${AWS::Partition} pseudo parameter in ARNs instead of hardcoding "aws",
so the template works across partitions (aws, aws-cn, aws-us-gov, aws-eusc).

Resources:
  ExecRole:
    Type: AWS::IAM::Role
    Properties:
      RoleName: AmazonECSroleCF
      AssumeRolePolicyDocument:
        Version: "2012-10-17"
        Statement:
          - Effect: Allow
            Principal:
              Service:
                # IAM service principals are "amazonaws.com" across all partitions,
                # so this stays literal (do NOT use ${AWS::URLSuffix} here).
                - "ecs-tasks.amazonaws.com"
            Action: "sts:AssumeRole"
      ManagedPolicyArns:
        # Use ${AWS::Partition} rather than hardcoding "aws" in the ARN.
        - !Sub "arn:${AWS::Partition}:iam::aws:policy/service-role/AmazonECSTaskExecutionRolePolicy"

Outputs:
  ExecRoleArn:
    Description: ARN of the created ECS task execution role
    Value: !GetAtt ExecRole.Arn

Account structure and governance

AWS Control Tower offers a straightforward way to set up and govern an AWS multi-account environment, following prescriptive best practices. AWS Control Tower orchestrates the capabilities of several other AWS services, including AWS Organizations, AWS Service Catalog, and AWS IAM Identity Center, to build a landing zone in less than an hour. Resources are set up and managed on your behalf.

We recommend following the AWS Security Reference Architecture (AWS SRA) multi-account model structure for a EUSC deployment. Use the management account only for governance, deploy universal security guardrails through service control policies (SCPs), resource control policies (RCPs), and service deployments (such as AWS CloudTrail) that will affect all member accounts in the organization.

Region-deny SCPs are commonly applied in commercial Regions, but aren’t required (at this time) in the EUSC because of the physically and logically separated nature of its design.

Other possible SCPs for the management OU:

  • Service-level guardrails – Restrict which AWS services can be used, based on your compliance posture.
  • Network perimeter controls – Enforce virtual private cloud (VPC) endpoints, deny public access patterns, and restrict egress.
  • Encryption and key management – Require AWS Key Management Service (AWS KMS) managed keys for all data-at-rest services and enforce key policies aligned with your sovereignty requirements.

Note: As additional EUSC Regions or Local Zones become available, the partition boundary continues to enforce isolation from non-EUSC Regions. If you need to restrict usage to a subset of EUSC Regions (for example, only eusc-de-east-1 but not a future eusc-de-west-1), a Region-deny SCP would become relevant at that point.

Identity: IAM Identity Center as IaC, no direct payer access

IAM Identity Center is available in the AWS European Sovereign Cloud as an independent instance within the partition. You can connect it to your external identity provider (IdP)—Microsoft Entra ID, Okta, and so on—using SAML/SCIM, exactly as in AWS commercial Regions. If you already use Identity Center to federate in the commercial partition, you can point a second Identity Center integration at the same corporate IdP, so users keep one set of credentials. You manage permission sets, groups, and account assignments separately for each partition.

Manage permission sets and assignments as code

The following Terraform defines a permission set with both an AWS managed policy and an inline least-privilege policy, then assigns a group to a target account. Reproduce the aws_ssoadmin_account_assignment for each account or organizational unit (OU) mapping.

Because group membership comes from your IdP over SCIM, the IdP handles joiner, mover, and leaver, and access in EUSC updates automatically. No one receives direct access to the management account; all human access flows through IAM Identity Center permission sets assigned to non-management accounts.

data "aws_ssoadmin_instances" "this" {}
data "aws_partition" "current" {}

# Workload account the group is assigned to.
variable "analytics_workload_account_id" {
  type        = string
  description = "Account ID of the workload account to assign the permission set to"
}

locals {
  sso_instance_arn  = tolist(data.aws_ssoadmin_instances.this.arns)[0]
  identity_store_id = tolist(data.aws_ssoadmin_instances.this.identity_store_ids)[0]
}

resource "aws_ssoadmin_permission_set" "analytics_operator" {
  name             = "AnalyticsOperator"
  description      = "Operate analytics workloads; no IAM or billing"
  instance_arn     = local.sso_instance_arn
  session_duration = "PT4H"
}

# Attach an AWS managed policy
resource "aws_ssoadmin_managed_policy_attachment" "analytics_ro" {
  instance_arn       = local.sso_instance_arn
  permission_set_arn = aws_ssoadmin_permission_set.analytics_operator.arn
  managed_policy_arn = "arn:${data.aws_partition.current.partition}:iam::aws:policy/ReadOnlyAccess"
}

# Add a least-privilege inline policy (note the partition-aware ARNs)
resource "aws_ssoadmin_permission_set_inline_policy" "analytics_inline" {
  instance_arn       = local.sso_instance_arn
  permission_set_arn = aws_ssoadmin_permission_set.analytics_operator.arn
  inline_policy = jsonencode({
    Version = "2012-10-17"
    Statement = [{
      Sid      = "OperateAnalyticsData"
      Effect   = "Allow"
      Action   = ["s3:GetObject", "s3:PutObject", "s3:ListBucket"]
      Resource = [
        "arn:${data.aws_partition.current.partition}:s3:::analytics-*",
        "arn:${data.aws_partition.current.partition}:s3:::analytics-*/*"
      ]
      Condition = { StringEquals = { "aws:RequestedRegion" = "eusc-de-east-1" } }
    }]
  })
}

# Group for analytics operators.
# In production this is typically synced from your IdP via SCIM; here we
# manage it directly so the config is self-contained.
resource "aws_identitystore_group" "analytics" {
  identity_store_id = local.identity_store_id
  display_name      = "analytics-operators"
  description       = "Analytics operators"
}

# Assign the group to a workload account with the permission set
resource "aws_ssoadmin_account_assignment" "analytics_to_workload" {
  instance_arn       = local.sso_instance_arn
  permission_set_arn = aws_ssoadmin_permission_set.analytics_operator.arn
  principal_id       = aws_identitystore_group.analytics.group_id
  principal_type     = "GROUP"
  target_id          = var.analytics_workload_account_id
  target_type        = "AWS_ACCOUNT"
}

Cross-account roles for governance, logging, and tooling

Cross-account roles within the EUSC partition work normally; this is how the logging and security-tooling accounts collect from workload accounts. Scope each trust policy to a specific principal and harden it with an external ID (for third-party tooling) and partition-aware ARNs.

{
  "Version": "2012-10-17",
  "Statement": [{
    "Effect": "Allow",
    "Principal": {
      "AWS": "arn:${AWS::Partition}:iam::<SECURITY_TOOLING_ACCOUNT_ID>:role/SecurityAuditCollector"
    },
    "Action": "sts:AssumeRole",
    "Condition": {
      "StringEquals": { "sts:ExternalId": "eusc-sec-audit" },
      "ArnLike": { "aws:PrincipalArn": "arn:${AWS::Partition}:iam::*:role/SecurityAuditCollector" }
    }
  }]
}

A role in the aws partition can’t assume a role in aws-eusc (or the reverse).

Logging and monitoring: centralized in EUSC, exported to your SIEM

A sovereign logging architecture requires three things:

  • A single, immutable store for all audit and operational logs
  • A central security account that runs detective controls and correlates findings
  • A reliable, in-partition path that feeds everything into your SIEM without data ever leaving the boundary.

In the subsections that follow, we walk through each layer: Centralized log collection in the Log Archive account, Amazon GuardDuty and AWS Security Hub administration through the Security Tooling account, and the pull-based SIEM integration pattern that keeps telemetry inside the EUSC partition.

Centralize logs in the Log Archive account

The Log Archive account holds the organization trail and a central log bucket as part of the landing zone. In the commercial AWS partition, global services like IAM route their CloudTrail events to us-east-1. In the EUSC, global services events are logged within the EUSC partition because the control plane is independent and located entirely within the EU.

Organization level detective services

GuardDuty and Security Hub are available in EUSC, but organization-wide auto-enable and some newer features might differ from commercial AWS features at any given time. Design the Security Tooling account as the delegated administrator where supported. If org-level auto-enable isn’t yet available, enable per-account through your IaC (AWS CloudFormation StackSets) so coverage is complete and code-managed. Treat the EUSC service and feature list as the source of truth and gate optional features behind a partition flag.

Network security and perimeter, including AWS Direct Connect

The AWS European Sovereign Cloud has its own sovereign AWS Direct Connect points of presence (PoPs), with dedicated networking infrastructure and connectivity from European providers, providing customers an autonomous network path into the partition. You terminate Direct Connect in a dedicated Network account and share connectivity to workload VPCs using Transit Gateway (with AWS RAM). A Direct Connect connection or Direct Connect gateway in the commercial partition can’t be extended into aws-eusc. To reach EUSC VPCs, you provision a separate Direct Connect connection that lands in the EUSC partition’s Network account. If your on-premises network already backhauls to AWS commercial Regions, you connect that network to EUSC with its own virtual interface or connection, or a site-to-site VPN. You don’t bridge the two AWS partitions through a shared Direct Connect gateway.

The following figure shows the recommended perimeter design in EUSC.

Figure 1: Recommended perimeter design in EUSC

Figure 1: Recommended perimeter design in EUSC

The perimeter design includes:

  • Centralized egress and inspection – Route workload egress through an inspection VPC in the Network account (gateway load balancer with your firewall of choice, or AWS Network Firewall. Keep workload VPCs private with no internet gateway.
  • Private service access – Use VPC interface endpoints (VPCe) for AWS service calls so traffic stays on the AWS network within the partition. VPCe doesn’t cross partitions; expose any commercial-partition service to EUSC consumers over DX/VPN and an in-EUSC load balancer.
  • DNS – EUSC has its own Amazon Route 53. For names that must resolve across clouds, use subdomain delegation or Resolver forwarding rules over your DX or VPN link rather than expecting hosted zones to be visible across partitions.
  • Segmentation as code – Express segmentation with security groups referencing prefix lists and keep the EUSC IP ranges current from the partition’s published ip-ranges file in your firewall automation.

Data protection

AWS Key Management Service (AWS KMS) is available in EUSC; use customer managed keys for all sensitive data stores and enforce their use with SCPs and key policies. Where your residency or operational-autonomy requirements call for it, evaluate AWS KMS external and imported key material options available in the partition.

For workloads where regulation mandates that key material never resides within the cloud provider’s infrastructure, configure an AWS KMS External Key Store (XKS) in the EUSC Region. The XKS proxy connects AWS KMS to your EU-based hardware security module (HSM) (on-premises or hosted with an EU trust service provider); all encrypt and decrypt operations are performed by your external key manager. Note the trade-offs: increased latency, reduced availability SLA, and added operational burden. Reserve XKS for the subset of data where regulatory or contractual obligations explicitly require it.

The EUSC Region has achieved SOC 2, BSI C5 Type 1 attestation, and seven ISO certifications, including ISO 27001, 27017, 27018, and 27701. Reference these in your data protection evidence packages when demonstrating encryption-at-rest and key management controls to EU regulators.

Secure CI/CD and distributing images across the partition boundary

If you need to deploy existing images or binaries into EUSC (aws-eusc) from existing AWS commercial (aws) accounts, you can’t use cross-partition Amazon Elastic Container Registry (Amazon ECR) replication, Amazon Machine Image (AMI) copy, or Amazon Simple Storage Service (Amazon S3) replication. Instead, treat EUSC as an independent supply-chain destination:

  • Container images – Build (or re-tag and re-sign) images and push to an Amazon ECR registry inside EUSC. ECR cross-Region replication works within the partition (useful as EUSC adds Regions or Local Zones), but the initial crossing from commercial is an explicit pipeline push using EUSC credentials. Sign images with a sovereign signing key and verify at deploy time.
  • AMIs and images – Rebuild golden images in EUSC with EC2 Image Builder (run the pipeline natively in EUSC), or import virtual machine (VM) images using Amazon S3 in EUSC and aws ec2 import-image. There is no direct cross-partition AMI copy.
  • Binaries and artifacts – Stage in an artifact bucket in the EUSC Shared Services account. Move packages across the boundary with aws s3 sync or AWS DataSync over your DX or VPN, or using controlled export, then distribute within the partition using in-partition S3 replication to other EUSC Regions or Local Zones as they come online.
# Push a container image to ECR inside EUSC (note the .eu endpoint).
# Credentials/profile must be for the aws-eusc partition.
aws ecr get-login-password --region eusc-de-east-1 --profile eusc-shared-services \
  | docker login --username AWS --password-stdin \
    111122223333.dkr.ecr.eusc-de-east-1.amazonaws.eu

docker tag company/runtime:7.x \
  111122223333.dkr.ecr.eusc-de-east-1.amazonaws.eu/company/runtime:7.x
docker push \
  111122223333.dkr.ecr.eusc-de-east-1.amazonaws.eu/company/runtime:7.x

Remember that endpoints and ARNs use amazonaws.eu in the EUSC partition. IAM service principals always use amazonaws.com regardless of partition.

Replicating deployment code and pipelines

Run a native deployment plane in EUSC (AWS CodePipeline, AWS CodeBuild, AWS CodeDeploy, or your existing tool deployed in-partition) in the Shared Services account, with cross-account deploy roles into workload accounts. If a commercial-partition continuous-integration system must deploy into EUSC, give it separate credentials for each partition; the clean pattern is OIDC federation with two trust configurations, one for each partition, because no cross-partition role assumption exists.

// Deploy role in an EUSC workload account, trusted by the EUSC Shared Services pipeline role
{
  "Version": "2012-10-17",
  "Statement": [{
    "Effect": "Allow",
    "Principal": { "AWS": "arn:aws-eusc:iam::<SHARED_SERVICES_ACCT>:role/PipelineDeployRole" },
    "Action": "sts:AssumeRole",
    "Condition": { "StringEquals": { "sts:ExternalId": "EUSC-deploy" } }
  }]
}

For account vending and landing-zone-as-code, use Account Factory for Terraform (AFT) deployed in EUSC. AFT pipelines create accounts through AWS Control Tower, apply baseline guardrails, bootstrap the preceding partition-aware modules, and register OUs, giving you the accounts and account groups as code. Keep Terraform state for each partition in an in-EUSC Amazon S3 backend with an Amazon DynamoDB lock table; don’t share state across partitions.

The Landing Zone Accelerator on AWS (LZA) solution is an alternative deployment method that provisions a baseline security architecture and includes customizations for each partition, with consideration for service availability. A customized configuration baseline for European Sovereign Cloud was recently released and is accompanied by the LZA Compliance Workbook, which maps regional European security standards and international frameworks to over 200 security settings deployed by LZA.

Supported compared to by-design boundaries: A quick reference

Capability Status in EUSC What to do
AWS Control Tower account vending, controls Supported in-partition Govern the EUSC Region; drive vending with AFT; re-register OUs after Region changes
AWS Control Tower–managed or self-managed IAM Identity Center Configuration choice Choose self-managed to own permission sets as code
Permission set creation and assignment as IaC Supported Manage with SCIM groups from your IdP
Identity Center single home and delegated admin for each partition By-design behavior Administer from one Region; non-issue in single-Region EUSC
Cross-account roles (governance, logging, tooling) Supported within partition Scope trust to specific principals and ExternalId
Cross-partition AssumeRole, VPC peering, TGW, RAM, Amazon S3 replication Not available (security boundary) Integrate at network or API layer with separate per-partition credentials
Billing roll-up across accounts and Regions Supported within the EUSC org Aggregate in a finance or governance account in-partition
Billing roll-up across the aws and aws-eusc boundary Separate billing systems (EUR payer) Keep cost analysis in-partition or in an EU-resident tool
Multi-Region image distribution (Amazon ECR, AMI, and Amazon S3) Supported within partition Push into EUSC first, then replicate in-partition
GuardDuty and Security Hub Available—some org-auto-enable and features vary Delegate admin where supported; per-account enable using IaC otherwise
CloudFront, Shield Advanced, Firewall Manager, Inspector In planning at time of publication Follow on AWS Builder Center (capabilities) for release updates

Billing and cost governance

Roll up within the EUSC organization, not across partitions. Enable consolidated billing in the EUSC management account and deliver AWS Data Exports (Cost and Usage Report 2.0) to an S3 bucket in a dedicated finance or governance account in the Security or Infrastructure OU.

Set permissions so workload teams can query the curated data in that account; no one should be able to access the management or payer account directly. You can’t replicate billing data into the commercial partition; the EUSC has a separate payer (billed in EUR through the EU contracting entity).

Conclusion

Architecting in the AWS European Sovereign Cloud is, in most respects, architecting a second well-run AWS landing zone with one organizing principle that resolves nearly every design question: it’s an independent partition. Centralization of governance, identity, logging, and billing is fully achievable, but within the EUSC partition. The boundaries you encounter between commercial AWS and EUSC—no cross-partition roles, peering, replication, or billing roll-up—are the sovereignty guarantees doing their job.

Build the foundation as code. Use an AWS Control Tower landing zone driven by AFT, IAM Identity Center permission sets and assignments in Terraform federated to your corporate IdP, an immutable central log store, customer managed encryption keys constrained to the sovereign Region, and a Network account terminating a dedicated Direct Connect. Add a CI/CD plane that pushes images and artifacts into the partition with per-partition credentials. Keep every ARN partition-aware and every optional service behind a feature flag, and the same modules will serve both clouds.

To accelerate your build with additional enablement from AWS, explore the LZA Universal Configuration for European Sovereign Cloud on GitHub, which packages many of the patterns described in this post into a ready-to-deploy baseline. To complement your deployment with compliance readiness, the LZA Independent Assessment Report for C5:2020 evaluates how LZA’s security baseline maps to C5:2020 technical requirements, and you can download the report and the LZA Compliance Workbook from AWS Artifact.

Further reading

If you have feedback about this post, submit comments in the Comments section below or start a thread on AWS re:Post.


Pablo Pagani

Pablo Pagani

Pablo is a Systems Development Manager for AWS European Sovereign Cloud, based in Madrid, Spain. He has previously held roles within Enterprise Support and Professional Services. An active member of the Security Technical Field Community, he helps customers build a secure journey on AWS. Pablo developed his passion for computers while writing his first lines of code in BASIC on an MSX computer with 64 KB of RAM.

Margo Cronin

Margo is an EMEA Principal Solutions Architect specializing in Security & Compliance and is based out of Zurich Switzerland. Her interests include security, privacy, cryptography, and compliance. She is passionate about her work unblocking security challenges for AWS customers, enabling their successful cloud journeys. She is an author of the “AWS User Guide to Financial Services Regulations and Guidelines in Switzerland”.

AWS STS simplifies session token size limits and adds session token size monitoring

16 September 2026 at 00:21

AWS Security Token Service (AWS STS) has simplified session token size limits, giving you more room for your session policies and session tags. STS has replaced the packed policy size and the overall session token size limits with a single token size limit of 4,096 bytes. STS now reports session token size in API responses, Amazon CloudWatch metrics, and AWS CloudTrail events. By using STS, you can also generate session tokens of different sizes, so you can find the maximum token size that your infrastructure can support.

The 4,096-byte limit is the current maximum, not a permanent ceiling. AWS might increase the limit as new capabilities are added that require session tokens to carry more information.

In this post, you learn what has changed, what this change means for you, and what to do next.

What has changed

AWS STS session-vending APIs, such as AssumeRole, AssumeRoleWithSAML, AssumeRoleWithWebIdentity, GetSessionToken, and GetFederationToken, return temporary security credentials: an access key ID, a secret access key, and a session token. This change governs the session token, the opaque string that STS creates from the session policies and tags you pass plus the context that AWS adds.

Three things have changed.

  • A single limit: Previously, STS enforced two size limits on the session token. It serialized and compressed your session policies and tags into a form called the packed policy, which had its own limit. The assembled token, which included the packed policy, had a separate overall limit. A request could fail against either limit, and both failures returned the same PackedPolicyTooLargeException, so you couldn’t tell which one you exceeded. STS now enforces a single limit: the assembled session token must fit within 4,096 bytes. The separate packed policy limit, which made failures hard to predict, has been removed. When a token exceeds the assembled session token limit, STS returns PackedPolicyTooLargeException. STS continues to use the same exception, so existing error-handling code works without an SDK update.
  • Session token size is now reported. Every successful response from an STS session-vending API includes SessionTokenSize (which reports the session token size in bytes) and SessionTokenUtilization (which reports the percentage of the 4,096-byte limit consumed). STS also returns PackedPolicySize in every successful response for backward compatibility. PackedPolicySize now reports the same value as SessionTokenUtilization, enabling applications that use older AWS SDK versions to monitor utilization through this field. These response fields are also recorded in CloudTrail events. In CloudWatch, SessionTokenSize and SessionTokenMaxSize (the enforced limit) are published in the AWS/STS namespace.
  • Testing is more straightforward: MinimumSessionTokenSize is a new optional parameter on the STS session-vending APIs. You can use it to increase a session token to at least the size you specify, up to 4,096 bytes. Use the parameter to find the maximum token size your infrastructure can handle.
Behavior Previously Now
Limits enforced Two: Packed policy size and assembled token size One: Assembled session token size (4096 bytes)
Error on failure PackedPolicyTooLargeException: The error message didn’t identify which of the two limits was exceeded. PackedPolicyTooLargeException: The updated message reports your session token size and the maximum allowed size, both in bytes.
Session token size visibility Not reported

API Response and AWS CloudTrail:

SessionTokenSize, SessionTokenUtilization, and PackedPolicySize. PackedPolicySize reports the same percentage as SessionTokenUtilization for backward compatibility.

Amazon CloudWatch:

SessionTokenSize and SessionTokenMaxSize

Infrastructure testing No mechanism MinimumSessionTokenSize: Parameter on sesssion-vending APIs

What this change means for you?

How this affects you depends on your situation. The following scenarios cover the most common cases.

  • If you have never hit a token size error: You’re unlikely to notice a change. Your tokens stay their current size and gain headroom. Over time they could become larger than your systems have handled before. We recommend you use MinimumSessionTokenSize to find the maximum token size your systems can handle. See the What to do next section for more details.
  • If you’ve hit PackedPolicyTooLargeException before: Some requests that previously failed now succeed under the single limit. Review any workarounds you put in place specifically to avoid token size errors and decide whether you still need them. General best practices still apply: consistent tag casing and reused tag values compress more efficiently, and concise session policies keep the assembled token smaller. No code change is required for error handling. AWS STS still returns PackedPolicyTooLargeException when the assembled session token exceeds the limit, the same exception STS returned before this change.
  • If your systems enforce their own size limits on credentials: If your application uses an AWS SDK to obtain temporary credentials and make AWS API calls, the SDK handles the session token internally, so token size doesn’t affect your code. Focus instead on systems that store or forward session tokens, such as load balancers, proxies, caches, and databases. These systems might have size limits that smaller tokens didn’t reach. For example, a database column defined as varchar(2048) can’t hold a 4,096-byte token. Review where you persist or pass session tokens, and identify the maximum token size each system supports. The next section shows how to test this.

What to do next

We recommend the following three steps to prepare your systems for this change.

  1. Validate the maximum token size your systems can handle. Use MinimumSessionTokenSize to find the maximum session token size each system in your infrastructure can handle. Knowing these limits helps you identify systems that might reject or truncate larger tokens. The 4,096-byte limit reflects today’s needs, not a permanent ceiling. It might grow as AWS introduces new capabilities such as additional context keys for new services, richer audit metadata, and larger cryptographic signatures as the industry transitions to post-quantum algorithms. Avoid hard-coding the current maximum into your systems and revisit any fixed size assumptions if the limit changes.

    Tip: AWS STS serializes and compresses your session policies and tags when assembling the token. Compression results vary based on the actual content, not just its length. Two sets of tags with identical character counts can produce different token sizes. This is why MinimumSessionTokenSize is a more reliable way to test your infrastructure than estimating from input length.

    aws sts assume-role \
      --role-arn arn:aws:iam::123456789012:role/MyRole \
      --role-session-name validation-test \
      --minimum-session-token-size 4096

    Start at 4,096 bytes to test against the largest possible token. If a system truncates or rejects it, lower the value to find the size your infrastructure supports, then raise that limit where you can. MinimumSessionTokenSize is available in the latest AWS SDK, AWS Command Line Interface (AWS CLI), and Tools for PowerShell versions. See the STS API Reference for details. If your AWS SDK or AWS CLI predates the parameter, update it to use this feature.

  2. Monitor your session token size (recommended). If your infrastructure has size constraints, you can use monitoring to see tokens that are approaching your limit and act before a request fails. AWS STS reports size through three channels, each suited to a different need.
    • In the API response: Reading SessionTokenUtilization and SessionTokenSize from the response requires the latest AWS SDK version. You can also monitor token size through CloudWatch and CloudTrail without updating your SDK.
    {
      "Credentials": {
        "AccessKeyId": "REDACTED",
        "SecretAccessKey": "REDACTED",
        "SessionToken": "REDACTED",
        "Expiration": "2026-06-30T12:00:00Z"
      },
      "AssumedRoleUser": { "...": "..." },
      "PackedPolicySize": 61,
      "SessionTokenSize": 2532,
      "SessionTokenUtilization": 61
    }
    • In CloudWatch: STS publishes SessionTokenSize and SessionTokenMaxSize in the AWS/STS namespace. Use them to build dashboards and set alarms. Set your alarm against the size limit you found during testing, not the 4,096-byte maximum. The maximum is the same for every account, so your own infrastructure limit is the one that matters.

    The following figure shows the SessionTokenMaxSize and SessionTokenSize metrics graphed in the CloudWatch console.

    Figure 1: SessionTokenMaxSize and SessionTokenSizemetrics in the CloudWatch console

    Figure 1: SessionTokenMaxSize and SessionTokenSizemetrics in the CloudWatch console

    • In CloudTrail: Each STS session-vending event records SessionTokenUtilization and SessionTokenSize for successful calls.
    {
      "eventName": "AssumeRole",
      "responseElements": {
        "credentials": { "...": "..." },
        "assumedRoleUser": { "...": "..." },
        "packedPolicySize": 61,
        "sessionTokenUtilization": 61,
        "sessionTokenSize": 2532
      }
    }
  3. Use appropriate fields for monitoring session token utilization. AWS STS still returns PackedPolicySize in session-vending API responses and CloudTrail records for backward compatibility. The field now reports the same value as SessionTokenUtilization: the percentage of the 4,096-byte session token size limit consumed by the token. As a result, PackedPolicySize values might appear lower even when your token content has not changed.

    If your SDK exposes SessionTokenUtilization, use that field because its name reflects the value’s current meaning. If an earlier SDK does not expose SessionTokenUtilization, use PackedPolicySize to monitor the same utilization percentage without updating the SDK. We recommend you monitor SessionTokenSize for the token size in bytes.

Conclusion

You now have more room for session tags, tag values, and session policies in your AWS sessions. AWS STS enforces a single 4,096-byte session token limit, returns a clearer error message when a token exceeds it, and reports token size so you can track growth proactively. Validate your token-handling systems with MinimumSessionTokenSize, and watch SessionTokenUtilization and SessionTokenSize for ongoing visibility.

References

If you have feedback about this post, submit comments in the Comments section below.


Rishi Tripathy

Rishi Tripathy

Rishi is a Principal Product Manager on the AWS Identity and Access Management (IAM) team. He focuses on access control mechanisms that help enterprises secure their AWS environments at scale. He is passionate about building security primitives that are straightforward to adopt and hard to misconfigure.

Tanmay Baid

Tanmay Baid

Tanmay is a Senior Software Development Engineer on the AWS Identity and Access Management (IAM) team. He works on the core identity systems behind the credentials and tokens customers rely on to access AWS at massive scale. He enjoys working on the hard problems at the intersection of distributed systems, identity, and security.

Architecting resilient authentication with Amazon Cognito multi-Region replication

15 September 2026 at 21:00

Your consumer identity and access management (CIAM) system is the foundation of your customer experience. It’s how users sign in, access services, and engage with your applications. As your business scales across geographies, ensuring authentication is always available becomes a core architectural requirement. However, building multi-Region authentication has traditionally required complex custom replication solutions that synchronize user data, manage consistency, and handle failover, all adding significant operational overhead. Amazon Cognito simplifies this with multi-Region replication (MRR), which automatically replicates user pools across AWS Regions with near-real-time synchronization, built-in failover, and seamless sign-in, while keeping operational complexity and costs optimized.

In this post, we show you how to prepare your user pool for MRR, provide architectural decisions and reference architectures for business to consumer (B2C), business to business (B2B), and machine to machine (M2M) use cases, and practical guidance on implementing failover strategies.

Amazon Cognito MRR at a glance

Amazon Cognito MRR creates a replica user pool in another AWS Region (a replica Region) that shares the same user pool ID as your primary user pool. The primary user pool (the user pool in your primary Region) remains authoritative, and its configurations (app client IDs, client secrets), user data (attributes, hashed credentials, group memberships), and external identity provider (IdP) settings are replicated to the replica with eventual consistency.

The user pool in the replica Region (replica user pool) supports user authentication operations (such as sign-in, token generation and revocation) and read-only operations towards user pool configurations and user attributes (such as list users and groups and describe user pool configurations). Write operations against user pool configurations and updating user attributes aren’t enabled in the replica user pool and can only be made in the primary user pool. Amazon Cognito returns an Action temporarily unavailable error when using managed login, or an OperationNotEnabledException when using an AWS SDK for those operations. See Supported API operations in secondary Regions for a list of API operations supported in replica Regions.

JSON web tokens (JWTs) and active sessions are interoperable between Regions; for example, a refresh token issued by the primary Region is accepted in the replica Region to retrieve new ID and access tokens.

While this post primarily focuses on MRR architecture patterns and considerations, you can visit the following posts to learn more about MRR basics and the next-generation infrastructure behind it:

Prepare for multi-Region replication

In this section, we show you architectural decisions and preparation work for a successful MRR deployment.

Apply a multi-Region customer managed key

Without MRR enabled, data is encrypted at rest with an AWS owned AWS Key Management Service (AWS KMS) key and encrypted in transit with TLS 1.2 and TLS 1.3 with hybrid post-quantum key exchange. Before enabling MRR, you must configure your user pool to use a customer managed key. This must be a symmetric multi-Region AWS KMS customer managed key.

Architectural considerations for your KMS key:

  • You only need to set up one replica multi-Region key for your customer managed key because Amazon Cognito MRR supports only one additional replica Region.
  • You own the administration of the customer managed key, including key policies, rotation, and deletion. You can also consider a key rotation strategy before enabling MRR or enable automatic key rotation.
  • Follow least-privilege principles in KMS key policy and scope the KMS key to your user pool only. You can do so by applying a condition statement: kms:EncryptionContext:aws:cognito-idp:<userpool-arn>. See the data encryption section in the Amazon Cognito developer guide for a full example key policy.

Choose a multi-Region OIDC issuer

In each ID and access tokens, Amazon Cognito includes a default Issuer claim in the JWT payload, referred as iss, to represent the identity provider that issued the token. The OpenID Connect (OIDC) specification dictates that the iss format must be a URL that uses https scheme and publishes a JSON metadata document about the identity provider available at the <iss>/.well-known/openid-configuration path. The metadata document must also include the JSON Web Key (JWK) document in the <iss>/.well-known/jwks.json path, which contains the signing keys to validate the token signatures for its integrity.

The original issuer type follows the format as https://cognito-idp.<region>.amazonaws.com/<userpool_id>. However, this issuer URL format and the OIDC well-known metadata are regional resources. As part of the MRR capability, Cognito introduces a new multi-Region OIDC issuer type, the updated issuer, and follows the format as https://issuer-cognito-idp.<region>.amazonaws.com/<userpool_id>. This new updated issuer type replaces the original single Region type and maintains availability of the issuer endpoint regardless of the state of primary or replica Region.

Based on the issuer URL format you select, your OpenID Connect discovery endpoint is hosted at  <iss>/.well-known/openid-configuration and your JSON Web Key Set (JWKS) endpoint at <iss>/.well-known/jwks.json. Both original type and updated type are supported with the Amazon Cognito MRR capability. You can change the issuer type at any stage in your MRR journey, and the newly issued tokens, including those generated by refresh tokens, will reflect the most current issuer type configurations.

We recommend adopting the updated issuer type. With the updated issuer type, the OpenID Connect discovery document and JWKS endpoint remain consistent and available regardless of which Region is servicing requests. This means your applications can always fetch signing keys for token verification, even during a regional impairment.

To adopt the updated issuer type, update your applications and downstream dependencies to validate against the new updated iss value. If you use the aws-jwt-verify library, update to v5.2.1 or later that supports updated issuer type. Plan this as a coordinated deployment; existing ID and access tokens with the original issuer type remain valid and accepted by Amazon Cognito endpoints until they expire. When using an existing refresh token to exchange for a new set of ID and access tokens, new tokens always carry the current issuer format configuration at the time of token refresh operation, providing interoperability across two issuer formats.

If you can’t immediately adopt the multi-Region issuer—for example, because downstream services or third-party integrations validate the iss claim against a hard-coded original format pattern—you can enable MRR while continuing to use the original issuer type. However, in this configuration the OIDC discovery endpoint and JWKS endpoint are tied to a single Region and might be unavailable during a regional impairment. Your multi-Region application might not be able to fetch public keys dynamically and validate token signatures. To mitigate this, it’s a good practice to implement a JWKS caching strategy in your token verification layer. Cache the signing keys locally (respecting the Cache-Control headers) so your applications can continue to validate tokens using cached keys when the JWKS endpoint is unreachable. This approach lets you benefit from MRR for user authentication while maintaining token verification continuity until you’re ready to complete the issuer migration. To learn more about the original and updated issuer types, see the Amazon Cognito user pools as an OIDC issuer section of the developer guide.

Configure regional service dependencies

Amazon Cognito user pools support several integrations with AWS services for extended customization functionalities. Those AWS services are regional services and must be configured independently in the replica Region, including:

  • AWS Lambda – Lambda triggers (for example, pre-authentication, pre-token generation, and others) are invoked in different authentication stages and should be deployed in the replica Region and attached to the replica user pool to match customized behaviors in the primary user pool. When deploying Lambda triggers, you can adopt the same logic for both primary and replica user pools and access to downstream resources or set up a different logic to characterize different behaviors when requests are served in the replica Region.
  • AWS WAF – WAF web access control lists (web ACLs) are associated to protect the user pool from unwanted requests. When accepting traffic to the replica user pool, create matching WAF web ACLs in the replica Region.
  • Amazon Simple Notification Service (Amazon SNS) – If you send text messages (for example, SMS-based multi-factor authentication (MFA), passwordless authentication, or SMS notifications), configure Amazon SNS in the replica Region. SNS requires additional set up (origination identities, spending limits) in each Region, and sender ID registration time depends on several factors.
  • Amazon Simple Email Service (Amazon SES) – If you use Amazon SES for email delivery, verify sending domains and email addresses in the replica Region and configure your replica user pool accordingly.
  • Amazon CloudWatch – If you export user activity logs from Amazon Cognito to a CloudWatch log group, or monitor service quotas in CloudWatch, configure alarms and analytics accordingly.

Use infrastructure-as-code tools like AWS CloudFormation or AWS Cloud Development Kit (AWS CDK) to maintain consistent configurations and deployments across Regions and environments. You should also monitor for any configuration drifts between assets.

Consider automatic domain failover

For authentication use cases that rely on managed login and OAuth 2.0 endpoints—including federated authentication and M2M authorization—Amazon Cognito supports automatic failover to the replica Region with an Amazon Route 53 health check. Cognito uses the health status of Route 53 health check to control whether traffic routes to the primary or replica user pool. The health check can be set up to monitor the health of an endpoint, a CloudWatch alarm, or a calculated number of other health checks, so you determine what triggers a healthy or unhealthy state and can adjust traffic routing as needed.

Both the Amazon Cognito prefix domain (for example, auth.us-east-1.amazoncognito.com) and custom domain (for example, auth.example.com) support automatic domain failover. Your domain serves as the single entry point for the user pool OAuth 2.0 endpoints and directs traffic to the managed login pages. Cognito automatically fails over domain traffic to the replica Region when a Route 53 health check becomes unhealthy and fails back to the primary Region when the check is healthy. You don’t need to create another prefix domain in the replica user pool for failover use cases.

With the automatic failover capability, you can use a single domain to serve external IdP configurations, including redirect URIs and SAML assertion consumer URLs. For example, use https://auth.example.com/saml2/logout to send SAML 2.0 sign-out responses. Because the domain can serve traffic to both the primary and replica Regions and remains unchanged across Regions, your external IdP configurations stay consistent across Regions, and existing federated users continue to authenticate without disruption. This means that you can enable MRR without having to contact external IdP admins to update configurations; all existing configurations will continue to work.

For SDK-based authentication use cases without managed login, a custom domain isn’t strictly required. We recommend configuring a custom endpoint for SDK requests to simplify failover orchestration, so you don’t have to modify the Region parameter in the SDK configuration. Behind your custom endpoint, you can use the same Route 53 health check or a custom load balancing strategy to proxy API requests to primary or replica Region endpoints. You might also consider load balancing user authentication traffic, by referring to an X-Amz-Target HTTP header (for example, X-Amz-Target: AWSCognitoIdentityProviderService.InitiateAuth), to both the primary and replica Regions, while keeping user sign-up operations in the primary Region. If you use both managed login and SDK authentication in the same user pool, you can consider using the custom domain as the custom endpoint of the SDK for a streamlined operation, where Route 53 health check initiates failover and failback between the primary and replica Regions.

Plan for TOTP MFA alternatives

Time-Based One-Time Password (TOTP) MFA isn’t supported in replica user pools. Users configured to use TOTP MFA must authenticate through the primary Region. If your application relies on TOTP as a second factor, this limitation requires careful planning because you want to enable an alternative MFA for your users, such as SMS OTP, email OTP, or passkey.

Review quotas

When you activate a replica user pool, you gain a separate set of default quotas in the replica Region. Previously reserved higher quotas for your user pool in the primary Region aren’t carried over to the replica Region.

Data sovereignty

When selecting a replica Region for your user pool, consider your organization’s data sovereignty and residency requirements, as user identity data will be replicated to and stored in that Region. For guidance on navigating compliance, continuity, and control obligations that may influence your Region selection, see Practical digital sovereignty: Navigating the pillars of compliance, continuity, and control.

Reference architectures

In this section, we show you reference architectures for common authentication patterns using the Amazon Cognito MRR capability. Each architecture demonstrates how Cognito MRR works with different authentication use cases.

Managed login and federation

Amazon Cognito managed login provides a fully managed authentication UI that handles sign-in, sign-up, and federation flows. With MRR, managed login endpoints are served from the healthy user pool based on your Route 53 health check configuration. Managed login also includes OAuth 2.0 endpoints and can be used with local Cognito accounts and federated users. Figure 1 depicts a reference architecture for using managed login to authenticate Cognito users.

Figure 1: Cognito MRR reference architecture for managed login and federation use cases

Figure 1: Cognito MRR reference architecture for managed login and federation use cases

When using Amazon Cognito with managed login, the process flow is:

  1. The user visits the application and is redirected to the managed login to begin the authentication flow.
  2. Managed login uses the Route 53 health check to control traffic routing.
  3. If the health check returns a healthy status, all traffic to the managed login flows to the primary Region user pool for user authentication.
  4. For a federated user, the primary Region user pool redirects the user to a federated IdP or social IdP for authentication. After successful authentication, Amazon Cognito creates or updates user attributes depending on whether it’s a new user signing in for first time or an existing user.
  5. If the health check returns an unhealthy status, all traffic to the managed login flows to the replica Region user pool. Cognito users will authenticate against the replica user pool.
  6. The replica Region user pool endpoint redirects federated users to external IdPs. However, any user creation or attribute update against replica user pool will fail until the health check returns healthy and traffic routes back to the primary Region.

M2M architecture

In an M2M architecture, services authenticate using the OAuth 2.0 client credentials grant. This flow doesn’t involve users; instead, backend services exchange client credentials for access tokens.

Figure 2: Cognito MRR reference architecture for machine-to-machine use case

Figure 2: Cognito MRR reference architecture for machine-to-machine use case

The authentication flow is:

  1. Application clients send a POST request to the Amazon Cognito /token endpoint with client credentials.
  2. Managed login uses the Route 53 health check to determine whether traffic should flow to the primary or replica user pool.
  3. If the health check returns a healthy status, traffic to the /token endpoint will flow to the primary Region user pool.
  4. If the health check returns an unhealthy status, traffic to the /token endpoint will flow to the replica Region user pool. After the health check returns to a healthy status, traffic will return to routing to the primary user pool.

SDK-based architecture

For applications that use AWS SDK or Amazon Cognito APIs directly (rather than through managed login), the authentication flow is embedded in your application code. This gives you more control over the user experience but requires additional considerations for failover.

Figure 3: Cognito MRR reference architecture for SDK use cases

Figure 3: Cognito MRR reference architecture for SDK use cases

The process shown in Figure 3 is:

  1. The user visits the application and signs in through a custom UI (using APIs or SDKs).
  2. (Optional) An Amazon Route 53 health check is configured to perform a health check against regional proxy endpoints and determine traffic routing. You can also use a custom health check or your DNS resolver to make traffic routing determinations.
  3. If the health check returns a healthy status, all traffic to the proxy endpoints will flow to the primary Region proxy for user authentication. You can also choose to load balance user authentication traffic across both the primary and backup Regions.
  4. The primary Region Amazon API Gateway proxy forwards user requests to the Amazon Cognito regional endpoint.
  5. If the health check returns an unhealthy status, all traffic will flow to the replica Region proxy.
  6. The replica Region API Gateway proxy begins forwarding user requests to the Amazon Cognito regional endpoint until the health check returns to healthy status.

In an SDK-based architecture, Amazon Cognito regional endpoints can also be called directly. You can also set up custom routing to use replica Region endpoints to load balance user authentication requests by routing read-only requests to both the primary and replica Region endpoints while keeping write requests in the primary Region.

Failover strategies

Now that you’ve set up multi-Region replication with Amazon Cognito, the next step is to test and monitor your multi-Region configuration. In this section, we walk through strategies for monitoring your endpoints, determining when to trigger failover, and testing your failover readiness.

Monitor with Route 53 health checks

Failover for Managed Login and all OAuth 2.0 flows is driven by Amazon Route 53 health checks associated with your Amazon Cognito prefix or custom domain. You’re responsible for what determines the state of this health check. The health check isn’t tied to your DNS CNAME record but is the signal that tells Amazon Cognito whether to route traffic to the primary or replica Region for all managed login endpoints. When the health check fails, Amazon Cognito routes traffic to the replica user pool. When the health check recovers, traffic is restored to the primary user pool.

A practical approach to get started to build a health check:

  1. Create a synthetic canary – Use Amazon CloudWatch Synthetics to run a canary that periodically exercises an actual authentication flow against your primary Region. For example, the canary can perform a client credentials token request against your Amazon Cognito domain’s /oauth2/token endpoint or execute a full AdminInitiateAuth API call with test credentials. This validates that the end-to-end authentication path is functional, not just that an endpoint is responding.
  2. Tie the canary to a CloudWatch alarm – Configure a CloudWatch alarm on the canary’s SuccessPercent CloudWatch metric. Set a threshold that accounts for transient errors (for example, alarm when success drops below 90% for three consecutive evaluation periods).
  3. Connect the alarm to your Route 53 health check (optional) – Create a Route 53 health check that monitors the CloudWatch alarm. When the alarm enters the ALARM state, the health check fails, and Amazon Cognito routes traffic to the replica user pool. If you prefer to rely on human intervention, skip this step and instead configure the CloudWatch alarm alert your operations team to manually invert the health check.

After you have your health check, associate it with your Amazon Cognito domain using the UpdateUserPoolDomain API or the Amazon Cognito console.

Authentication-only compared to full-stack failover

Before implementing failover, consider how your authentication layer relates to the rest of your application stack. There are two common patterns:

  • Authentication-only failover – Your application remains in a single Region, but authentication traffic fails over to the Amazon Cognito replica if only the primary Region’s authentication service is impaired. This works when your application can continue operating with tokens already issued (for example, cached JWTs, active sessions) and when downstream APIs don’t depend on the same Region as your user pool. Consider this option when the rest of your stack has its own availability model.
  • Full-stack failover – Your entire application—compute, data stores, APIs, and authentication—fails over to a replica Region. In this model, Amazon Cognito MRR is one component of a broader multi-Region architecture where authentication flows have tight dependencies on regional resources (such as Lambda triggers calling regional Amazon DynamoDB tables, or post-authentication logic writing to a regional event bus) that must be co-located with the user pool.

Use Amazon Application Recovery Controller (ARC) to coordinate failover across all components with a single action. ARC provides three capabilities that are particularly relevant for multi-Region authentication architectures:

  • Routing controls – Extremely reliable data plane controls that let you shift DNS traffic across Regions, with safety rules that prevent partial or unintended failovers (for example, preventing you from failing over authentication without also failing over the dependent API layer).
  • Readiness checks – Continuous monitoring of resource quotas, capacity, and network routing policies in your secondary Region, so you have confidence that the replica environment—including your Amazon Cognito replica user pool and its regional dependencies—can handle production traffic before you failover.
  • Region switch – Centralized, automated, and observable multi-Region recovery orchestration across multiple AWS accounts and resources, so you can execute a coordinated failover of your Cognito user pool alongside databases, compute, and APIs in a single recovery plan.

ARC is particularly valuable when your Amazon Cognito Lambda triggers, WAF rules, SNS and SES configurations, and downstream services all need to switch Regions in lockstep. Rather than managing failover for each component independently, you can use ARC to define a single recovery group that treats your authentication stack and application stack as one unit. To learn more about the capabilities and use cases of ARC, see Introducing Amazon Route 53 Application Recovery Controller.

The right choice depends on your recovery scope. Map the dependencies in your authentication flow: if your Lambda triggers call regional DynamoDB tables or your post-authentication logic writes to a regional event bus, those tight couplings point to full-stack failover. If your application validates tokens independently and doesn’t make real-time calls back to Amazon Cognito after token issuance, authentication-only failover keeps both your blast radius and operational overhead smaller.

Determine when to failover

Triggering failover too aggressively risks unnecessary disruptions; too conservatively risks a drop in desired availability. Here are the factors to balance:

  • Monitor authentication flow health – Validate that critical flows are functioning, including managed login endpoint availability and token endpoint responses.
  • Use composite health checks – Combine multiple signals. For example, require both the managed login and token endpoints to be healthy.
  • Set appropriate thresholds – Configure failure thresholds (for example, three consecutive failures) to distinguish transient errors from genuine impairments.
  • Consider downstream dependencies – Factor in Lambda triggers, external IdPs, and other regional services.
  • Client side retry logic – For SDK-based single-page application (SPA) architectures, consider implementing client-side retry logic with Region failover. When the primary Region is unavailable, your application should detect the failure and redirect authentication of API calls to the replica Region’s Amazon Cognito endpoint.

Understanding and determining the recovery time objective (RTO) and recovery point objective (RPO) should also be the key factor in determining when and why to failover. See the Establishing RPO and RTO Targets for Cloud Applications blog post to learn more.

Test failover readiness

If using Route 53 health check, start by manually inverting your Route 53 health check during a maintenance window. In the Route 53 console, enable Invert health check status to force the health check into a failed state; this triggers failover to the replica Region without requiring any infrastructure changes. While traffic is routing to the replica Region, validate that your critical authentication flows (sign-in, token refresh, federation) work correctly, then disable the inversion to restore traffic to the primary. This test confirms your end-to-end failover path is functional.

When you’re confident in the basic failover path, graduate to more realistic failure simulations with AWS Fault Injection Service (FIS). Create FIS experiment templates that disrupt your primary Region’s Amazon Cognito dependencies; for example, block network access to a dependent resource or inject latency into downstream API calls. Use FIS stop conditions (guardrails) to automatically halt experiments if unexpected impacts are detected. These experiments validate not just that failover triggers correctly, but that your replica Region handles real authentication load under degraded conditions.

We recommend conducting failover tests on a predefined and regular cadence and after any significant changes to your authentication architecture. Document your runbooks and make sure your operations team is familiar with both the failover and recovery procedures.

Conclusion

In this post, we built on the foundational knowledge of the Amazon Cognito MRR capability and showed you how to architect resilient authentication for real-world use cases:

  • Preparation considerations – Multi-Region KMS keys, OIDC issuer transitions, regional dependencies, and TOTP MFA considerations
  • Reference architectures – B2C, B2B, and M2M patterns using managed login, plus SDK-based approaches
  • Failover strategies – Route 53 health checks, ARC integration, and testing with health check inversion and AWS FIS

To get started, make sure your user pool is on the Essentials or Plus feature plan, configure your multi-Region KMS key and OIDC issuer, and create your first replica. For step-by-step setup instructions, see Multi-Region replication for user pools

If you have feedback or thoughts about this post, submit comments below. If you have questions, start a new thread on Amazon Cognito re:Post or contact AWS Support.


Abrom-Douglas-author

Abrom Douglas III

Abrom is a Senior Solutions Architect within AWS Identity with over 20 years of software engineering and security experience, specializing in identity and access management. He loves speaking with customers about how identity and access management can provide secure outcomes that enable both business and technology initiatives. In his free time, he enjoys cheering for Arsenal FC, photography, travel, volunteering, and competing in duathlons.

Edward Sun

Edward Sun

Edward is a Senior Security Specialist Solutions Architect focused on identity and access management. He loves helping customers throughout their cloud transformation journey with architecture design, security best practices, migration, and cost optimizations. Outside of work, Edward enjoys hiking, golfing, and cheering for his alma mater, the Georgia Bulldogs.

Operationalizing least privilege: Automate IAM remediation through your CI/CD pipeline

15 September 2026 at 17:53

The principle of least privilege is straightforward to articulate but challenging to maintain at scale. When teams first deploy applications to AWS, they often grant broader permissions than strictly necessary; it’s faster to get things working, and the plan is always to tighten permissions later. But later rarely comes. Permissions accumulate, AWS Identity and Access Management (IAM) principals that once needed broad access for initial deployment retain those permissions long after they’re necessary, and some principals stop being used entirely. Even small teams face this challenge—permission reviews aren’t a one-time task but an ongoing operational burden that demands automation.

AWS IAM Access Analyzer addresses detection and recommendation. It identifies unused permissions across IAM roles and users: actions that haven’t been exercised, services that haven’t been accessed, and principals that aren’t being assumed at all. For each finding, it generates a recommended policy with the excess permissions removed. Security teams can see exactly what to fix, but manual remediation doesn’t persist. A security engineer can right-size a role today, but if that role is defined in an AWS CloudFormation template or AWS Cloud Development Kit (AWS CDK) stack, the next deployment restores the original permissions. The fix must live where the role is defined, and not every role starts in the same place. Some are managed through infrastructure-as-code (IaC), where remediation means updating source code and deploying through a pipeline. Others were created manually through the AWS Management Console and have no code representation. And some principals aren’t being used at all and need a controlled decommission path. Each scenario requires a different remediation strategy.

This post walks through an automated remediation workflow that bridges the gap between detection and action. Instead of findings accumulating in a dashboard waiting for someone to investigate, the automation classifies each role by how it was created and produces a ready-to-review remediation artifact: a pull request with production-ready CDK code and a plain-English explanation for IaC-managed roles, an issue with the recommended policy and step-by-step IaC migration guidance for manually created roles, or a soft-disable issue with a monitored decommission plan for unused principals. Each output flows through your existing code review and issue tracking processes—the same workflows your teams already follow. By the end of this post, you’ll have a pattern that converts IAM Access Analyzer findings into tested, deployable code changes rather than a growing backlog of security tickets.

Understanding the problem

Unused IAM permissions increase the attack surface. Removing unused permissions limits the actions available to any compromised credentials, reducing potential impact. Roles that aren’t being assumed represent unused resources; removing them simplifies your IAM inventory and reduces potential access paths that aren’t actively monitored.

The challenge isn’t knowing what to fix. As we said earlier, Access Analyzer provides both the findings and the recommended policies. The challenge is acting on that knowledge consistently across your environment. Each finding requires context:

  • What the role does
  • Who created the role
  • Determining if the permission is unused or used infrequently
  • If the role is managed in a CloudFormation stack, or was created through the console

Multiply this by hundreds of roles and security teams face a backlog that grows faster than they can address it.

Manual remediation compounds the problem. A security engineer can right-size a role directly in the console, but that fix is fragile. If the role is defined in an IaC template, the next deployment restores the original permissions. If it was created manually, there’s no record of what changed or why, and no easy way to revert if the change causes issues.

This is where IaC changes the equation. When roles are defined in code, remediation means updating that code. Changes flow through pull requests, are reviewed by the team that owns the role, and deploy consistently across environments. The fix becomes permanent, not a point-in-time correction that drifts back on the next deployment. And because every change is tracked in version control, teams can confidently remove permissions knowing they can revert if something breaks. That safety net matters; it’s often the difference between a team acting on a finding and leaving it in the backlog.

Solution overview

The solution automates remediation by connecting four capabilities: IAM Access Analyzer for detection and policy recommendations, CloudTrail for role attribution, Amazon Bedrock for CDK code generation and plain-English explanations, and your existing continuous integration and delivery (CI/CD) pipeline for remediation execution. The workflow operates on a core principle: every IAM role has an origin, and that origin determines the remediation path.

Figure 1 shows the solution architecture: Amazon EventBridge triggers an AWS Lambda orchestrator on a daily schedule. The Lambda orchestrator integrates with IAM Access Analyzer, CloudTrail, Amazon Bedrock, and Amazon CloudWatch. Each finding is routed to one of three remediation paths: a pull request for IaC-managed roles, an issue for manually created roles, and a soft-disable issue for unused roles.

Figure 1: The daily remediation workflow; from scheduled trigger to the three role-based remediation paths

Figure 1: The daily remediation workflow; from scheduled trigger to the three role-based remediation paths

On each scheduled run, the automation retrieves active findings from IAM Access Analyzer and queries CloudTrail to determine how each role was created. Roles created through CloudFormation or AWS CDK have a traceable origin: the service principal, stack name, and originating repository. Roles created manually through the console have a different origin: the IAM user who created them and the timestamp. This distinction drives the remediation strategy.

For IaC-managed roles, the automation retrieves the IAM Access Analyzer-recommended policy and uses Amazon Bedrock to wrap it in production-ready CDK code that includes the role definition and policy statements and imports what your CI/CD pipeline needs to deploy the update. It then creates a pull request in the originating repository. The pull request (PR) includes the updated CDK code, a policy diff showing exactly which permissions are being removed, and a plain-English explanation of the changes, for example, “This change removes write access to S3, keeping only read and list permissions.” Your existing code review process evaluates the change, and after being merged, the fix deploys consistently across environments.

For manually created roles, the automation creates an issue that includes the IAM Access Analyzer-recommended policy with unused permissions removed, a diff highlighting the changes, and an Amazon Bedrock-generated explanation of what the permission changes accomplish. The issue also provides guidance on importing the role into your IaC codebase. This gives teams an immediate remediation path while encouraging long-term governance through IaC adoption.

For roles that aren’t being assumed at all, the automation takes a more cautious approach. Instead of taking direct action, it creates an issue recommending a soft-disable workflow: attach a deny-all policy to the role, monitor for 30 days to confirm no workload depends on it, then delete. The issue provides the steps and context, the team executes the decommission through their preferred process, whether that’s a console change, an AWS Command Line Interface (AWS CLI) script, or a PR removing the role from the IaC. This controlled decommission path reduces the risk of removing a role that’s used infrequently or seasonally.

The solution supports both single-account and organization-wide deployment. In single-account mode, it uses an ACCOUNT_UNUSED_ACCESS analyzer to process findings for one account. In organization mode, it uses an ORGANIZATION_UNUSED_ACCESS analyzer deployed in a delegated administrator account, which generates findings across all member accounts from a single vantage point. The Lambda function automatically detects which analyzer type is available and extracts the account ID from each finding’s resource Amazon Resource Name (ARN), so role attribution and remediation routing work the same way regardless of scope.

This three-path strategy acknowledges operational reality. Not all roles start in IaC, not all unused roles are safe to delete immediately, and forcing immediate migration isn’t always practical. The solution provides a clear path forward for each scenario: remediate IaC roles through code, give teams actionable recommendations for manually created roles, and safely decommission what’s no longer needed. Over time, your infrastructure becomes increasingly code-driven, and remediation becomes a routine part of your CI/CD process rather than a manual security task.

Technical details

Consider a company—call them AnyCompany—running 200 IAM roles across three AWS accounts. Some roles were created through AWS CDK stacks during initial deployment. Others were created manually through the console by engineers who needed quick access during incident response or prototyping. A handful haven’t been assumed in over 6 months. AnyCompany’s security team wants to act on their IAM Access Analyzer findings, but each role requires different handling. The solution’s architecture addresses this by routing each finding through a classification and remediation pipeline.

Figure 2 shows how each IAM Access Analyzer finding is processed:

  1. The finding is first checked against exclusions and excluded findings are skipped.
  2. Remaining findings are split by type: UnusedPermission findings retrieve a recommended policy from IAM Access Analyzer and then query CloudTrail for role origin, while UnusedIAMRole findings follow the unused role path.
  3. By origin, IaC-managed roles generate AWS CDK code using Amazon Bedrock and create a pull request.
  4. Manually created or unknown-origin roles create an issue with the recommended policy and IaC migration guidance.
  5. Unused roles create a soft-disable issue to deny-all, monitor for 30 days, then delete.
  6. All paths publish CloudWatch metrics.
Figure 2: Detailed component interactions—the orchestrator’s five steps, its four service integrations, and the three remediation paths

Figure 2: Detailed component interactions—the orchestrator’s five steps, its four service integrations, and the three remediation paths

The rest of this section walks through each component using AnyCompany’s roles as examples.

Exclusion filtering

Before processing any finding, the Lambda function loads an exclusion configuration and checks whether the role should be skipped. This prevents the automation from creating remediation items for roles that legitimately need broad permissions.

{
  "excluded_roles": [
    "arn:aws:iam::123456789012:role/BreakGlassRole",
    "arn:aws:iam::123456789012:role/ServiceLinkedRole"
  ],
  "excluded_permissions": [
    "iam:*",
    "sts:AssumeRole"
  ],
  "excluded_by_tag": {
    "NoRemediation": ["true"],
    "CriticalService": ["true"]
  },
  "min_unused_days": 30
}

AnyCompany excludes their break-glass role (used only during incidents), any service-linked roles, and roles tagged CriticalService. The min_unused_days threshold prevents false positives from seasonal workloads; a role that ran a quarterly batch job 25 days ago won’t generate a finding.

Detection and analysis

IAM Access Analyzer generates two types of findings relevant to this solution. UnusedPermission findings identify roles with permissions that haven’t been exercised within the analysis period. UnusedIAMRole findings identify roles that haven’t been assumed at all. The Lambda function queries both finding types separately because they follow different remediation paths.

The Lambda function auto-detects the analyzer type at startup. When ANALYZER_SCOPE is set to organization, it checks for an ORGANIZATION_UNUSED_ACCESS analyzer first and falls back to ACCOUNT_UNUSED_ACCESS if none exists. If multiple analyzers of the same type exist in the account, the Lambda function selects the first active analyzer returned by the API. To target a specific analyzer, set the ANALYZER_ARN environment variable explicitly. With an organization-level analyzer, findings include roles from all member accounts. The Lambda function extracts the account ID from each finding’s resource ARN (for example, account 111122223333 from arn:aws:iam::111122223333:role/MyRole) and carries that context through the entire pipeline: attribution, remediation, and issue or PR creation all include the originating account.

For UnusedPermission findings, the Lambda function calls GenerateFindingRecommendation to initiate policy generation, then retrieves the IAM Access Analyzer-recommended policy through the GetFindingRecommendation API. This is a key integration point: IAM Access Analyzer provides the right-sized policy with unused permissions removed, so the automation doesn’t need to generate policies itself.

Here’s what a typical finding looks like for one of AnyCompany’s application roles:

{
  "id": "a1b2c3d4-5678-90ab-cdef-example11111",
  "resource": "arn:aws:iam::123456789012:role/AnyCompanyOrderProcessorRole",
  "findingType": "UnusedPermission",
  "analyzedAt": "2026-03-01T00:00:00Z",
  "unusedPermissions": [
    { "action": "s3:PutObject", "lastAccessed": null },
    { "action": "s3:DeleteObject", "lastAccessed": null },
    { "action": "s3:PutBucketPolicy", "lastAccessed": null },
    { "action": "dynamodb:DeleteItem", "lastAccessed": null }
  ],
  "activePermissions": [
    { "action": "s3:GetObject", "lastAccessed": "2026-02-28T14:30:00Z" },
    { "action": "s3:ListBucket", "lastAccessed": "2026-02-28T14:30:00Z" },
    { "action": "dynamodb:Query", "lastAccessed": "2026-02-28T12:00:00Z" }
  ]
}

The OrderProcessorRole has write and delete permissions for Amazon Simple Storage Service (Amazon S3) and Amazon DynamoDB, but only uses read operations. The IAM Access Analyzer recommendation removes the four unused actions while preserving the three active ones.

For UnusedIAMRole findings, no recommendation is needed: the role isn’t being assumed at all, so the remediation is to disable or delete it. The Lambda function caps the number of unused role issues per run (configurable using MAX_UNUSED_ROLE_ISSUES, default 10) to avoid overwhelming teams with a flood of issues on the first execution.

Role attribution using CloudTrail

For each finding, the Lambda function queries CloudTrail to determine how the role was created. The CreateRole event contains the information needed to classify the role’s origin.

An IaC-created role looks like this in CloudTrail:

{
  "eventName": "CreateRole",
  "userIdentity": {
    "type": "AWSService",
    "invokedBy": "cloudformation.amazonaws.com"
  },
  "requestParameters": {
    "roleName": "AnyCompanyOrderProcessorRole"
  },
  "userAgent": "cloudformation.amazonaws.com"
}

The cloudformation.amazonaws.com service principal and user agent tell the automation this role was created through a CloudFormation or AWS CDK deployment. The Lambda function then looks up the role’s tags to find the originating repository (stored in a Repository tag set during deployment).

A manually-created role looks different:

{
  "eventName": "CreateRole",
  "userIdentity": {
    "type": "IAMUser",
    "userName": "jstiles"
  },
  "requestParameters": {
    "roleName": "AnyCompanyIncidentResponseRole"
  },
  "userAgent": "console.amazonaws.com"
}

Here, the IAMUser type and console.amazonaws.com user agent indicate someone created this role through the console. Roles created through the AWS CLI show a similar pattern: the IAMUser type with a user agent like aws-cli/2.x.x. The automation classifies both console and AWS CLI-created roles as manually created, because neither has an IaC origin that can be updated programmatically. The automation captures the username and timestamp for the remediation issue.

Cross-account role attribution

When the Lambda function processes findings from an organization-level analyzer, the role might live in a different account than the one running the function. The automation handles this by assuming a cross-account role (configurable using CROSS_ACCOUNT_ROLE_NAME, defaulting to OrganizationAccountAccessRole) in the member account, then querying that account’s CloudTrail and IAM APIs for the CreateRole event. If the cross-account assume fails—because the role doesn’t exist in that account or permissions aren’t configured—the automation falls back gracefully, classifying the role as unknown origin and creating an issue with the account ID and available context. This approach helps the automation produce an actionable output for findings even when attribution is incomplete.

Policy recommendations and AWS CDK code generation

For IaC-managed roles with UnusedPermission findings, the Lambda function retrieves the IAM Access Analyzer-recommended policy and sends it to Amazon Bedrock to generate production-ready AWS CDK code. This is an important distinction: IAM Access Analyzer decides what the policy should be, and Amazon Bedrock wraps that policy in the AWS CDK constructs, imports, and resource definitions that the CI/CD pipeline needs to deploy the update.

The prompt instructs Amazon Bedrock to convert the recommended policy to AWS CDK code exactly as provided, with no modifications:

Generate Python CDK code that creates/updates the role with the
RECOMMENDED policy exactly as provided. Include proper imports
(aws_cdk, aws_iam), use CDK best practices (PolicyStatement,
proper resource ARNs), and add tags: ManagedBy=CDK,
RemediatedBy=AccessAnalyzer.

IAM Access Analyzer generates recommendations for both inline policies and customer managed policies. When a managed policy has partially unused permissions, the recommendation contains the full right-sized policy. The automation wraps this in AWS CDK code as an iam.ManagedPolicy construct. Note that if a managed policy is shared across multiple roles, the recommendation applies to the specific role’s usage pattern. In this case, the automation generates an issue for manual review rather than a PR, because modifying a shared policy could affect other roles.

The generated code goes through a validation step before inclusion in any PR. The Lambda function compiles the Python code to check for syntax errors and verifies that required AWS CDK patterns (iam, PolicyStatement) are present. If validation fails, the finding is logged as an error rather than creating a broken PR.

The solution doesn’t currently invoke the IAM Access Analyzer ValidatePolicy API to check the generated policy for errors or overly permissive statements. However, this is a natural extension point. Teams can add a validation step that calls ValidatePolicy on the Amazon Bedrock-generated policy before including it in a PR, detecting issues like missing resource constraints or invalid action names.

Amazon Bedrock also generates a plain-English explanation of the policy changes. For AnyCompany’s OrderProcessorRole, the explanation might read:

“The role currently has full S3 write access and DynamoDB delete permissions, but only uses read operations. Removing s3:PutObject, s3:DeleteObject, s3:PutBucketPolicy, and dynamodb:DeleteItem reduces the scope of impact if credentials are compromised, while preserving the s3:GetObject, s3:ListBucket, and dynamodb:Query permissions the application needs.”

The solution uses the Anthropic Claude Sonnet model on Amazon Bedrock for CDK code generation (where accuracy matters) and Claude Haiku on Amazon Bedrock for explanations (where speed and cost efficiency matter more).

Three-path remediation

The Lambda function evaluates each finding’s origin and routes it to one of three remediation paths.

Path 1: IaC-managed roles (pull request) – For AnyCompany’s OrderProcessorRole, the automation creates a PR in the originating repository. The PR includes:

  • The Amazon Bedrock-generated AWS CDK code implementing the IAM Access Analyzer-recommended policy
  • A policy diff showing exactly which permissions are being removed
  • The plain-English explanation of what the changes accomplish
  • Labels (security, iam-remediation, automated) for filtering and tracking

The team that owns the role reviews the PR through their normal code review process. Once merged, the fix deploys consistently across environments through the existing CI/CD pipeline.

Path 2: Manually-created roles (issue) – For AnyCompany’s IncidentResponseRole, the automation creates an issue that includes the Access Analyzer-recommended policy with unused permissions removed, a diff highlighting the changes, an Amazon Bedrock-generated explanation, and step-by-step guidance on importing the role into IaC. This gives the team an immediate remediation path (apply the recommended policy) while encouraging long-term governance through IaC adoption.

Path 3: Unused roles (soft-disable issue) – For roles that haven’t been assumed at all, the automation creates an issue recommending a three-stage decommission workflow: attach a deny-all policy to the role, monitor for 30 days to confirm no workload depends on it, then delete. This controlled approach reduces the risk of removing a role that’s used infrequently or seasonally – if something breaks during the monitoring period, removing the deny-all policy restores access immediately.

Dry-run mode

Before creating real PRs and issues, you can run the automation in dry-run mode by setting “dry_run": true in the CI/CD configuration or setting the CI_CD_PLATFORM environment variable to dryrun. In this mode, the Lambda function processes findings, classifies roles, and generates remediation data, but logs what it would create instead of making actual API calls to your repository platform. You can use the log to validate the automation’s behavior, review the classification accuracy, and tune exclusions before going live.

Operational metrics

The Lambda function publishes CloudWatch metrics after each run:

findings_processed Total UnusedPermission findings evaluated
iac_roles_found Roles classified as IaC-managed
manual_roles_found Roles classified as manually created
unused_roles_found Roles with no assume activity (UnusedIAMRole findings)
prs_created Pull requests created for IaC roles
issues_created Issues created (manual roles and unused roles)
errors Processing errors (failed classifications, API failures)

These metrics feed into dashboards and alarms. AnyCompany sets an alarm on errors > 5 to catch API throttling or configuration issues, and tracks prs_created + issues_created over time to measure remediation velocity.

Implementation

The solution ships as two AWS CDK stacks and deploys in minutes. The accompanying GitHub repository contains the complete source code, AWS CDK stacks, configuration templates, and step-by-step deployment instructions.

At a high level, deployment involves:

  1. Prerequisites: An AWS account with an ACCOUNT_UNUSED_ACCESS or ORGANIZATION_UNUSED_ACCESS analyzer enabled, Python 3.11 or later, AWS CDK v2, a CI/CD platform API token stored in AWS Secrets Manager, and Amazon Bedrock model access for the Anthropic Claude models you plan to use. The model IDs are configurable environment variables (BEDROCK_CODEGEN_MODEL and BEDROCK_EXPLANATION_MODEL); Amazon Bedrock retires older foundation models over time, so if the shipped defaults stop working, set these variables to current models you have enabled and redeploy. The repository README documents this.
  2. Configuration: Two files in the config/ directory control behavior. exclusions.json defines which roles and permissions to skip (break-glass roles, service-linked roles, tagged exceptions), and ci_cd_config.json configures your repository platform integration (GitLab or GitHub), labels, and throttling limits.
  3. Deploy: Run cdk deploy --all to create the Lambda function, EventBridge schedule, IAM roles, and CloudWatch alarms.
  4. Validate in dry-run mode: Start with “dry_run": true to see how the automation classifies your roles without creating real PRs or issues. Review the CloudWatch logs to confirm attribution accuracy and tune exclusions.
  5. Go live: Set “dry_run": false and redeploy. The Lambda function runs on schedule (daily by default) and begins creating PRs and issues.

The repository README covers each step in detail, including organization-wide deployment, cross-account configuration, and platform-specific setup for GitLab and GitHub.

Operational considerations

Deploying the automation is only the starting point. Running it in production means making decisions about how roles are retired, how the volume of findings is managed at scale, which roles warrant human review before any change is proposed, and how you measure the automation’s impact over time. The following practices keep remediation sustainable as your IAM footprint grows, so the automation reduces operational burden rather than adding to it.

Unused role lifecycle

Unused roles follow a three-stage decommission workflow. When the automation identifies a role that hasn’t been assumed within the analysis period, it creates an issue with the recommended decommission steps; the automation doesn’t modify the role directly. The team then follows the soft-disable approach:

  1. Attach a deny-all inline policy to the role. This blocks all actions without deleting the role or its existing policies.
  2. Monitor for 30 days. If a workload depends on the role (seasonal jobs, infrequent batch processes), the deny-all policy surfaces the dependency quickly. Removing the deny-all policy restores full access immediately; no need to recreate the role or reattach policies.
  3. Delete the role after the monitoring period confirms no impact.

This approach is deliberately conservative. Deleting a role is irreversible; you lose the trust policy, attached policies, and any resource-based policies that reference it. The soft-disable step gives teams a safety net while still making progress on reducing their unused role inventory.

Scaling and throttling

On AnyCompany’s first run, the automation found 47 unused permission findings and 4 unused roles. That’s manageable. But organizations with hundreds of accounts and thousands of roles might see significantly more findings on initial deployment.

This is especially true with an organization-level analyzer. A single-account deployment might surface dozens of findings; an organization-level analyzer across multiple accounts could surface hundreds or thousands on the first run. The throttling controls become critical at this scale.

Two throttling controls prevent the automation from overwhelming teams:

  • max_findings_per_run (default 50): Caps the total UnusedPermission findings processed per Lambda function execution. Remaining findings are picked up on the next scheduled run.
  • MAX_UNUSED_ROLE_ISSUES (default 10): Caps unused role issues per run. This is especially important during initial deployment when you might have a large backlog of roles that haven’t been assumed in months.

Start with conservative limits and increase them as your team builds confidence in the review process. A team that can review 10 PRs per week shouldn’t receive 50 on Monday morning.

Approval workflows for sensitive roles

Not every role should receive automated PRs. Roles with administrative permissions or access to sensitive data might warrant manual review before any remediation is created. The exclusion configuration supports this through the approval_required_for_tags field:

{
  "approval_required_for_tags": {
    "Sensitive": ["true"],
    "Admin": ["true"]
  }
}

Roles matching these tags generate issues for manual review instead of automated PRs, regardless of whether they’re IaC-managed. This gives security teams a checkpoint for high-risk roles while still automating remediation for standard application roles.

Monitoring and alerting

The metrics published after each Lambda function run (covered in the Technical details section) feed into CloudWatch dashboards and alarms. A few patterns worth setting up:

  • Alert on errors > 5 per run to catch API throttling, expired CI/CD tokens, or Amazon Bedrock availability issues.
  • Track prs_created + issues_created over time. A healthy trend shows this number decreasing as your environment converges toward least privilege.
  • Monitor unused_roles_found as a leading indicator. A sudden increase might signal a team spinning up roles for a project and not cleaning up afterward.
  • Compare iac_roles_found to manual_roles_found over time. As teams adopt IaC, the ratio should shift toward IaC-managed roles, which means more automated remediation and less manual work.

Cost

The solution uses Lambda (minimal cost at daily execution), CloudTrail (typically already enabled), IAM Access Analyzer (charges per IAM role or user analyzed per month for the unused access analyzer), and Amazon Bedrock (pay-per-token for AWS CDK code generation and explanations). For most organizations the ongoing cost is low, and Amazon Bedrock token usage is the largest variable, scaling with the number of findings processed per day and the complexity of each policy. Review the pricing pages for each service for current rates.

For organization-level deployments, the IAM Access Analyzer cost scales with the number of IAM roles analyzed across all member accounts. The ORGANIZATION_UNUSED_ACCESS analyzer charges per role per month across the organization, so an organization with 500 roles across 20 accounts will see higher analyzer costs than a single account with 50 roles. Review the IAM Access Analyzer pricing page for current rates.

Cleanup

To remove the solution, run cdk destroy --all from the infrastructure/ directory. This removes the Lambda function, EventBridge rule, CloudWatch alarms, and IAM roles created by the stacks.

If you stored a CI/CD platform API token in Secrets Manager as part of deployment, delete it with aws secretsmanager delete-secret --secret-id <your-secret-name> --recovery-window-in-days 7. The 7-day recovery window lets you restore the secret if the deletion was accidental. After 7 days, the secret is permanently deleted and can’t be recovered. To delete immediately without a recovery window, add --force-delete-without-recovery.

Lambda automatically creates a CloudWatch Logs log group at /aws/lambda/<function-name> that persists after cdk destroy --all and continues to incur log storage charges. To remove it, run aws logs delete-log-group --log-group-name /aws/lambda/<function-name>. WARNING: This permanently deletes all execution logs.

The IAM Access Analyzer isn’t created by the AWS CDK stacks. WARNING: Deleting the analyzer permanently removes all findings, analysis history, and unused permission data. Export any findings you need to retain before deletion. After exporting, run aws accessanalyzer delete-analyzer --analyzer-name <your-analyzer-name> to delete it. The ACCOUNT_UNUSED_ACCESS and ORGANIZATION_UNUSED_ACCESS analyzer types incur charges based on the number of IAM roles and users analyzed per month.

If you deployed in organization mode and created cross-account roles (default name: OrganizationAccountAccessRole) in member accounts solely for this solution, remove them from those accounts.

Any PRs or issues already created in your CI/CD platform remain after stack deletion; they’re artifacts in your repository, not AWS resources. See the repository README for detailed cleanup instructions.,

Conclusion

Automating IAM permission remediation turns least privilege from a periodic compliance exercise into an operational practice. By connecting IAM Access Analyzer findings and recommendations to your CI/CD pipeline, remediation shifts from manual security tasks to code review processes that your teams already follow.

The three-path strategy acknowledges how infrastructure evolves. IaC-managed roles receive pull requests with production-ready AWS CDK code and plain-English explanations. Manually created roles receive actionable issues with recommended policies and IaC migration guidance. Unused roles are put on a controlled decommission path that protects against accidental disruption. Over time, the manual role count decreases as teams adopt IaC, and remediation becomes a routine part of your deployment pipeline.

Start with a pilot. Choose 10–20 non-production roles, deploy in dry-run mode, and review the classification results. Tune your exclusions, confirm the CloudTrail attribution is accurate for your environment, and then enable live remediation. Expand to production roles after your team is comfortable with the review cadence.

When you’re ready to scale beyond a single account, switch to an organization-level analyzer and the same Lambda function will process findings across all member accounts with no architectural changes required, only a configuration toggle.

The complete source code, AWS CDK stacks, and configuration templates are available in the accompanying GitHub repository.

If you have feedback about this post, submit comments in the Comments section below.


Luis Pastor

Luis E Pastor

Luis is a Senior Security Solutions Architect at AWS specializing in infrastructure security, compliance, and generative AI security. He leads technical field communities focused on security and compliance while contributing to AWS Well-Architected Framework guidance. Before AWS, he helped clients across financial services, healthcare, and retail industries improve their security posture in hybrid environments. Outside of work, Luis enjoys staying active and culinary adventures.

Rodolfo Brenes

Rodolfo Brenes

Rodolfo is a Principal Solutions Architect focused on Cloud Governance and Compliance. With over 18 years of experience, he currently leads a technical field community in AWS helping customers scale and improve their security and governance frameworks. Besides work, Rodolfo enjoys video games, playing with his four cats, and won’t say no to a good outdoor adventure.

Sowjanya Rajavaram

Sowjanya Rajavaram

Sowjanya is a Sr Solution Architect who specializes in Identity and Security in AWS. Her entire career has been focused on helping customers of all sizes solve their identity and access management problems. She enjoys traveling and experiencing new cultures and food.

Satish Uppalapati

Satish is an Associate Assurance Consultant with AWS Security Assurance Services (SAS) and has more than 8 years of experience in IT risk, governance, and regulatory assurance. He works with AWS customers to align cloud environments with multiple frameworks. Satish helps organizations build security and governance programs that meet regulatory objectives while supporting business operations. He also focuses on advancing governance for AI systems, including emerging standards.

Managing identity source transition for AWS IAM Identity Center

20 October 2026 at 18:47

October 20, 2026: This post was republished to reflect the new migration capability from Active Directory to an external identity provider (IdP) or the Identity Center directory, now available in IAM Identity Center.

September 2, 2026: This post was republished to include Active Directory migration strategies and automation for permission sets.


AWS IAM Identity Center manages user access to Amazon Web Services (AWS) resources, including both AWS accounts and applications. You can use IAM Identity Center to create and manage user identities within the Identity Center identity store or to connect to other identity sources.

Organizations that are switching identity providers (IdPs), consolidating identity infrastructure, adopting new single sign-on capabilities, or migrating off legacy on-premises systems may need to change the identity source in IAM Identity Center. Previously, migrations from Active Directory to another identity source deleted users, groups, memberships, and assignments at the moment of cutover. Now, migrations away from Active Directory preserve your users, groups, memberships, and assignments, just as transitions between an external IdP and the Identity Center directory already do. Only switching to Active Directory still removes users, groups, and assignments. Because the change applies to the entire Identity Center instance at once, test validation and a dress rehearsal are strongly recommended.

This post walks you through the migration process and provides sample code to assist the transition. It includes architectural guidance and a step-by-step runbook for switching from Active Directory to Okta. This guide helps AWS administrators, identity engineers, and project teams switch identity sources safely.

Note: This walkthrough uses Okta as a representative example of a SAML 2.0 identity provider. The inclusion of Okta in this example does not constitute an endorsement of any specific identity provider.

Identity source options in IAM Identity Center

The identity source is the definitive system of record: it determines which directory holds the primary copy of user identities and group memberships used for AWS access.

Each IAM Identity Center instance connects to one identity source at a time. IAM Identity Center supports three main identity sources:

  • Identity Center directory – The default identity store. Users and groups are created and managed directly within IAM Identity Center, with no dependency on an external provider. Suitable for organizations without an existing enterprise directory or those wanting a setup that uses only AWS services.
  • Active Directory – Integration with an on-premises Microsoft Active Directory or AWS Managed Microsoft AD through AWS Directory Service for Microsoft Active Directory. This lets organizations reuse their existing AD identities, group memberships, and access policies.
  • External IdP – Integration with third-party providers that support SAML 2.0, including Okta Universal Directory, Microsoft Entra ID (formerly Azure AD), Ping Identity, and others. This is the approach covered in the migration runbook that follows.

For example, migrating from Active Directory to an external IdP carries your existing users and groups over to the new identity source. IAM Identity Center keeps the same identity store, user IDs, and group IDs, and SCIM updates only the external identifier (externalId) to reflect the new source.

How access flows to AWS resources

IAM Identity Center grants access to AWS resources in two ways, as shown in Figure 1:

  • Permission set assignments – Users or groups are assigned permission sets within specific AWS accounts. This enables assume-role access, and AWS Identity and Access Management (IAM) roles (named AWSReservedSSO_...) are automatically created in each account to back these assignments.
  • Application assignments – Users or groups are granted access to AWS-managed applications (such as Amazon SageMaker Studio, Amazon OpenSearch Service and so on) and customer-managed applications integrated with IAM Identity Center.
Figure 1: Granting access to AWS resources for users and groups managed by an identity source in IAM Identity Center

Figure 1: Granting access to AWS resources for users and groups managed by an identity source in IAM Identity Center

When you change the identity source, the downstream impact on these assignments depends heavily on which sources you’re switching from and to. In some transitions, assignments remain intact.

When you switch the identity source from Active Directory to an external IdP or to the Identity Center directory, users, groups, user and group IDs, group memberships, and their associated assignments are preserved. Users keep their access to AWS accounts and applications after the new identity source takes over. Switching to Active Directory from any source removes users, groups, and assignments at the moment of cutover, so pre-migration backup and post-migration restoration are still essential in that scenario.

What changes when switching identity source in IAM Identity Center

Migrations away from Active Directory, and transitions between an external IdP and the Identity Center directory, now preserve users, groups, memberships, and assignments. Transitions to Active Directory removes users, groups, and assignments permanently from IAM Identity Center at the moment of cutover, as shown in the following table. For more information, see Considerations for changing your identity source.

IAM Identity Center item Status upon switch from AD to external IdP or Identity Center directory Status upon switch from external IdP or Identity Center directory to AD
Users and groups in Identity Center Preserved (same user and group IDs; the externalId changes as the new source takes over) Deleted (must be re-provisioned from AD)
Account assignments Preserved Deleted (must be recreated)
Application assignments Preserved* Deleted (must be recreated)

Note: *Test each application in a non-production environment before you migrate. Also inventory any assignments that live inside an application itself, because those sit outside IAM Identity Center.

Before you start: common blockers

  • Matching attribute – Confirm which attribute your target IdP uses to find an existing user (sometimes called matching precedence or existing resource lookup). The IdP must take over each existing Identity Center user and group rather than create a duplicate. Test this in a non-production environment.
  • Required attributes – Every user must have a username, first name, last name, and display name. If any required attribute is missing, that user silently fails to provision. If you send email, it must be unique and single-valued.
  • Username and NameID – Each user’s IdP userName must exactly match the existing Identity Center username, and the SAML NameID must map to the same value. Decide your sign-in identifier (for example, a legacy sAMAccountName or a UPN) before cutover.
  • Groups – Confirm that your IdP supports group provisioning through SCIM (for example, Google Workspace provisions users only). Group names must be unique, and renaming a group can cause it to be treated as new, which strands its assignments. Depending on the external Identity provider, users who belong to a group only through a nested group are not provisioned and lose group-based access. Inventory nested groups and directly assign the child groups that contain those users before cutover.
  • Emergency access – Set up a break-glass administrative access path that does not depend on AWS Identity Center.

Sample deployment

The following five-step summary (expanded into seven phases in the runbook that follows) applies to an identity source transition in IAM Identity Center from Active Directory to Okta, focusing on permission set assignments. The AD-to-Okta runbook in the next section expands each of these steps with specific instructions and commands. To assist users, you can also use the Identity Center migration tool script, which provides a structured workflow for Identity Center migrations with commands for precheck, cutover, validation, and cleanup. Because assignments are now preserved, the restore command is used only for manual rollback. The sample scripts and detailed steps are available on GitHub.

Note: This solution is available in the GitHub aws-samples repository. You can report bugs or make feature requests through GitHub Issues. The builders of this solution can help with GitHub issues. Enterprise Support customers can reach out to their Technical Account Manager (TAM) for further questions or feature requests.

Prerequisites

Before you start this walkthrough, make sure you have the following prerequisites in place:

  • Python 3.10 or later
  • AWS credentials configured using environment variables, an AWS configuration file, or a named AWS Command Line Interface (AWS CLI) profile (specified with --profile)
  • An active IAM Identity Center instance in the target account
  • Okta Global Admin access
  • Install the migration tool as described in the README file

Basic solution walkthrough

The following steps summarize the migration process. The next section expands each step with detailed Okta-specific instructions and commands.

Step 1: Back up users, groups, and assignments – Before making any changes, export your current identity data such as users, groups, and all assignments. This backup protects you if something goes wrong during migration. Store them in a secure, access-controlled location. The runbook includes a script that exports all current IAM Identity Center assignments and principals to a CSV file, then validates referential integrity.

Step 2: Prepare and validate users and groups in the target identity source – Before switching the IAM Identity Center identity source, confirm that your users and groups exist in the new authoritative source. Verify usernames, display names, email addresses, group names, group memberships and other required attributes. Each user’s userName in the new source must exactly match the existing Identity Center username, because this is how the new source usually takes over the user. In a test environment, confirm that an existing user is matched, not duplicated.

Step 3: Switch IAM Identity Center to the new identity source, and configure sign-in – Update IAM Identity Center to point to the new identity source. For external IdPs, upload the SAML metadata and configure the Assertion Consumer Service (ACS) and issuer URLs in your IdP. Before enabling SCIM (System for Cross-domain Identity Management), confirm that a pilot user can sign in.

WARNING: The identity source change applies to the entire Identity Center instance. After you confirm it, Active Directory sync and authentication stop, and users can’t sign in until SAML sign-in works with the new IdP. Users, groups, memberships, and assignments are preserved.

Step 4: Enable SCIM provisioning and verify takeover – Enable automatic provisioning and assign users and groups to the IAM Identity Center application in your IdP. The IdP takes over each existing user and group. Then run the validate command to compare the live assignments against your backup and find any missing or extra assignments.

If drift is found, the script writes a drift_report.csv file with MISSING and EXTRA entries.

Step 5: Validate access – Test access for a sample of users across different roles and permission levels before declaring the migration complete. Confirm that users can authenticate through the new identity source, access their expected AWS accounts, and assume the correct IAM roles. Confirm that the identity source shows your external IdP, that users and groups keep the same IDs, and that no duplicates were created.

Detailed runbook for Okta migration

This runbook covers one of the most common identity source transitions: migrating from an Active Directory to Okta as a SAML 2.0 identity provider.

The sample deployment describes what happens during a transition. It walks through seven phases: stakeholder alignment and pre-migration inventory, pre-cutover validation, the identity source switch itself, takeover verification, post-migration testing, ongoing cleanup and monitoring, and a documented manual rollback procedure for when things don’t go to plan.

If you’re migrating to Active Directory, which still removes users, groups, memberships and assignments, you can adapt the backup and restore scripts from this guide.

Phase 1: Plan your pre-migration activities

Pre-migration planning has four components: stakeholder engagement, inventory, scheduling, and access verification. Complete all four before you schedule the cutover.

1.1 – Document relevant stakeholders:

Fill out this table with actual contact information. You’ll need to reach these people during the cutover window.

Stakeholder Org Name Email Phone
Active Directory administrator Your organization
AWS administrator Your organization
Identity provider (IdP) administrator Your organization
Identity Center team/AWS Organizations administrator AWS account team
Application owners AWS account team
Identity provider (IdP) solutions architect AWS account team

1.2 – Inventory current state:

Before any changes are made, document the complete current state of your IAM Identity Center configuration. Capture a baseline of all three assignment layers: the users and groups assigned to the IAM Identity Center application in your IdP, the account and application assignments in IAM Identity Center, and any assignments inside the applications themselves:

Run the precheck script to export all current Identity Center assignments and principals to CSV.

```bash 
python -m idc_migration_tool precheck --output-dir ./export 
``` 

This will produce the following artifacts:

  • assignments.csv – One row per account, permission-set, and principal assignment
  • principals.csv – All users and groups from the identity store

1.3 – Define the cutover window:

Schedule the migration during a low-usage period to minimize user impact. Size the maintenance window using timings from a full-dress rehearsal in a test environment. SCIM provisioning is rate-limited, so for large directories, sync users in batches. Identify a maintenance window of sufficient length to complete all phases, including time for validation and potential manual rollback (described in Phase 7) if needed. Notify all affected users in advance of the potential temporary disruption to single-sign-on access.

1.4 – Confirm access requirements:

Verify that the following access is confirmed and tested before the cutover window:

  • AWS Administrator access to IAM Identity Center and AWS Organizations.
  • Identity provider (IdP) administrator access (for example, Okta) to configure the IAM Identity Center application, create the SCIM integration, and assign users to the AWS app.
  • A break-glass or emergency administrative access path that does not depend on the identity source you are migrating.

Phase 2: Complete final pre-cutover steps

Before starting the cutover, complete the final validation, access, and communication checks described in this phase.

2.1 – Export IAM Identity Center configuration:

Validate that the backup files generated in Step 1.2 are present and non-empty before proceeding.

2.2 – Communicate impact to users:

Send advance notice to all affected users covering:

  • The migration timeline and expected impact window.
  • That users can’t sign in between the identity source change and the new IdP’s sign-in going live, but that their access and assignments are unchanged.
  • The new sign-in process. After migration, users sign in through your IdP (for example, the Okta My Apps dashboard) or the AWS access portal, depending on the sign-in flow you choose.
  • Whether the new sign-in flow is IdP-initiated (through Okta) or SP-initiated (through the AWS access portal), and any differences in the user experience.
  • After migration, the d-xxxxxxxxxx.awsapps.com/start access portal URL is no longer supported, and the console shows the supported dual-stack regional URL (https://ssoins-<instance-id>.portal.<region>.app.aws) instead, so you must communicate the new URL and update bookmarks/allow-lists.
  • That the custom access portal alias (friendly URL) isn’t supported after migrating away from Active Directory. If a proxy or bookmark relies on redirect flows, plan to update it.

Prepare a user guide for the new sign-in process and an FAQ for common issues. Schedule a training session to demonstrate how to access AWS through Okta. Ensure your support team is briefed and ready to handle an influx of access issues during and immediately after the cutover.

2.3 – Validate Okta-to-IAM Identity Center sync (pre-cutover testing):

Using a sandbox or test environment if available, perform the following validation steps before executing against production:

  • Run the full migration in a test instance that mirrors your production AD configuration and applications and confirm that existing test users are matched by Okta and not duplicated.
  • Use the AWS Management Console for IAM Identity Center to verify that groups and users appear in Users & Groups with the correct attributes.
  • Test the complete end-to-end sign-in flow for a test user. Authenticate through Okta, access the AWS portal, and assume a role in a test account. Confirm that the user keeps access to their assigned accounts, permission sets, and applications.

Phase 3: Complete the cutover

You’re ready to configure Okta, switch the IAM Identity Center identity source, and complete the production cutover.

Important: Downtime begins when you confirm the identity source change in Step 3.2 and ends when SAML sign-in works through Okta. Have the Okta application, SAML metadata, and signing certificate ready before you start. Users, groups, memberships, and assignments are preserved.

3.1 – Configure the Okta application:

  1. Sign in to Okta as an administrator.
  2. Navigate to Applications and then to Browse App Catalog.
  3. Search for AWS IAM Identity Center and choose Add Integration. Choose Done.
  4. Choose the newly created app and select the Sign On tab.
  5. Locate the Metadata URL (it will look like: https://<your-okta-domain>/app/<app-id>/sso/saml/metadata). Open this URL in a new browser tab.
  6. An XML file will render in the browser. Save this file. This is your SAML metadata file, which will be uploaded to IAM Identity Center.
  7. Download and save the SAML signing certificate from the Sign On tab.

3.2 – Switch the identity source in IAM Identity Center:

  1. In the IAM Identity Center console navigation pane, choose Settings.
  2. Choose Actions and select Change Identity Source.

    Important: This change applies to the entire Identity Center instance. On the confirmation screen, you must enter ACCEPT to confirm. During this step and before SCIM provisioning is enabled, if the change could not be completed by Identity Center you will see a clear error message in the console to retry changing identity providers. It is safe to retry.

  3. Select External Identity Provider.
  4. Upload the XML metadata file and the SAML signing certificate downloaded from Okta.
  5. Confirm the change. IAM Identity Center will display progress updates as it migrates to the new identity provider.
  6. Don’t enable automatic provisioning yet. Complete Step 3.3 and confirm pilot sign-in in Step 3.4 first.

3.3 – Configure the ACS and issuer URLs in Okta:

  1. In the IAM Identity Center console, choose Settings and then Actions. Select Manage Authentication.
  2. Copy the IAM Identity Center Assertion Consumer Service (ACS) URL and the IAM Identity Center Issuer URL.
  3. Return to Okta and choose Applications and select IAM Identity Center app. Select the Sign On tab and choose Edit.
  4. Under Advanced Sign On Settings, paste the ACS URL and Issuer URL into the corresponding fields.
  5. Choose Save.

3.4 – Confirm pilot sign-in:

Before you enable SCIM provisioning, assign an existing pilot user to the IAM Identity Center application in Okta and confirm they can sign in through the AWS access portal. The SAML NameID that Okta sends must exactly match the user’s existing Identity Center username. If sign-in fails, fix the mapping now before proceeding to the next step.

3.5 – Enable automatic provisioning (console) and connect SCIM in Okta:

  1. In the IAM Identity Center console, choose Settings, then choose Enable Automatic Provisioning. Copy and securely record the SCIM endpoint URL and access token.
  2. Return to the IAM Identity Center app in Okta. Choose the Provisioning tab.
  3. Choose Configure API Integration.
  4. Paste the SCIM Endpoint URL into the Base URL field.
  5. Paste the Access Token into the API Token field.
  6. Choose Test API Credentials. You should receive confirmation that the credentials are valid.
  7. Choose Save.
  8. On the Provisioning page, choose Edit and under To App enable all three provisioning options (Create Users, Update User Attributes, and Deactivate Users). Choose Save. (The To App settings control how Okta provisions users to IAM Identity Center. All three options are required for the migration to work correctly.)
  9. On the Push Groups tab, push the groups that are assigned to the AWS application. Group names must exactly match the existing group names in IAM Identity Center.
  10. In the attribute mappings, confirm that userName maps to the existing Identity Center username and that first name, last name, display name, and a single email address are populated.

3.6 – Test SCIM takeover:

Before you assign all users, verify that Okta takes over existing users correctly:

  1. In Okta, select an existing pilot user who already exists in IAM Identity Center (People).
  2. Open the user and navigate to the Applications tab.
  3. Assign the AWS IAM Identity Center app to this test user.
  4. Wait 5–10 minutes for SCIM sync to run.
  5. In the IAM Identity Center console, select Users and confirm that the pilot user still has the same user ID, that no duplicate user was created, and that the user’s assignments still work.

    Note: If the user is duplicated or doesn’t update after 10 minutes, check the Okta System Log for SCIM provisioning errors and verify the SCIM endpoint URL and token are correctly configured.

  6. After the pilot user is taken over successfully, assign the remaining users and groups to the application in Okta. For large directories, assign them in batches.

Phase 4: Verify takeover

Now that you’ve completed cutover, verify that Okta has taken over all users and groups and that the preserved assignments match your pre-migration baseline.

4.1 – Verify SCIM takeover:

Confirm that all production users and groups are provisioned from Okta, that they keep the same user and group IDs, and that no duplicates were created. Check the Okta provisioning logs for errors such as “Refused to create a new, duplicate resource.”

4.2 – Check for assignment drift: Compare the live assignments against the pre-migration CSV

```bash 
python -m idc_migration_tool validate --csv ./export/assignments.csv --output-dir ./export 
```

If drift is found, the script writes a drift_report.csv file with MISSING and EXTRA entries. Because assignments are preserved, investigate any entries before you continue.

Phase 5: Post-migration validation

After the cutover, validate end-to-end access for representative user roles and confirm that assignments were preserved.

5.1 – Test end-to-end access:

Using a test Okta user account, complete the following validation steps:

  1. Sign in to the Okta Dashboard.
  2. Choose the AWS IAM Identity Center tile under My Apps.
  3. Select an assigned AWS account from the portal.
  4. Confirm that you can assume a role and access the AWS console.
  5. Test role switching within the console to validate permission boundaries.

5.2 – Spot-check multiple user types:

Validate access for a representative sample of users across different access levels, including Administrator, Developer, Read-Only or Audit, and any other standard roles defined in your environment. Confirm that permission sets are correctly mapped and that no unintended access has been granted or denied.

For each application, confirm that user-specific data and settings are intact and that any assignments inside the application still work.

Phase 6: Post-migration cleanup and monitoring

After confirming the migration is stable, shift focus to ongoing monitoring of provisioning and authentication, and update your operational documentation.

6.1 – Decommission AD only when stable:

  • Don’t decommission the Active Directory domain controllers until you’re confident the migration is stable and rollback is no longer needed. Keep AD online as a fallback. Deleting the AD directory removes the manual rollback option and the AD-based access portal endpoint.
  • The following command will identify disabled users, empty groups, and unassigned permission sets.
    ```bash 
    # Report only 
    python -m idc_migration_tool cleanup 
     
    # Report and prompt for deletion 
    python -m idc_migration_tool cleanup --delete 
    ```

6.2 – Monitor SCIM sync:

  • Confirm that SCIM provisioning continues to run without errors in the days following migration.
  • Monitor new user onboarding from Okta to verify that newly created Okta users are automatically provisioned into IAM Identity Center.
  • Review IAM Identity Center and AWS CloudTrail logs for failed sign-in attempts or unexpected authentication errors.

6.3 – Update documentation:

Update all internal documentation to reflect the new identity architecture:

  • Record the SCIM integration details, SAML metadata links, and new group-to-permission-set mappings.
  • Update internal SOPs and onboarding guides to reflect the new Okta-based login process.
  • Document troubleshooting procedures for the most common failure modes.

6.4 – Post-migration checklist:

Before closing the migration project, confirm all of the following:

  • Users can authenticate successfully through Okta.
  • Permission sets are correctly assigned to the correct users and groups.
  • Account assignments are working correctly across accounts.
  • Monitoring and logging are configured and alerting on anomalies.
  • Internal documentation and SOPs are updated.
  • Support team is trained on the new login process.
  • Rollback procedures have been reviewed and are ready if needed.
  • Active Directory integration cleanup is scheduled (do not rush decommission).

Phase 7: Rollback (if needed)

Rollback requires manually switching the identity source back to Active Directory, which deletes users, groups, memberships and assignments, and then rebuilding assignments from the pre-migration backup files, as described in the following steps.

Note: Define in advance what counts as a failure, who makes the rollback decision, and the acceptable discrepancy threshold. Only initiate rollback if the Okta migration has failed and cannot be recovered within the migration window. Rollback is a manual, time-consuming process. There is no single-button undo for an identity source switch.

7.1 – Switch identity source back to Active Directory:

  1. Navigate to IAM Identity Center and choose Settings, then Actions, and then Change Identity Source.
  2. Select Active Directory as the identity source.
  3. Select your existing AD domain. Ensure AD is still running and reachable before confirming.
  4. Accept the conditions and confirm the switch. Identity Center will display progress updates.
  5. When complete, choose Resume Sync, then choose Start Guided Setup.
  6. Confirm the attribute mappings and select the users and groups to sync.
  7. Review and save the configuration.

7.2 – Wait for AD users and groups to repopulate:

After completing the guided setup, AD users and groups will begin to reappear in IAM Identity Center through the directory sync. This might take several minutes depending on the size of your directory.

7.3 – Recreate account assignments:

Recreate the assignments from the pre-migration CSV file. This will resolve each principal name in identity store, create the assignment, and poll until completion, and produce a summary of succeeded, failed, and skipped counts.

```bash 
python -m idc_migration_tool cutover --csv ./export/assignments.csv 
```

7.4 – Validate access:

Confirm users can authenticate using the original AD-based AWS access portal URL and can access their expected AWS accounts and roles. Test key role types (such as Admin, Developer, and Audit) before declaring rollback complete.

Troubleshooting the cutover

The identity source change in Step 3.2 runs as a sequence of steps: stopping Active Directory sync, disconnecting the directory, and deleting the AD sync profile. If a step after “Stopping Active Directory sync” fails, the Confirm change screen reports which steps failed and offers a Retry failed steps button. You will see one of two error messages, both safe to retry:

  1. “The identity source change could not be completed. Please try again.” — AD sync was stopped but the directory wasn’t disconnected, so new users and changes are not currently syncing from Active Directory. Choose Retry failed steps to complete the transition. If instead you want to stay on Active Directory, choose Start guided setup in the Settings page to reconfigure the sync.
  2. “The identity source change could not be completed. Your identity source has been reverted to Active Directory. Please try again.” — IAM Identity Center automatically rolled back to a healthy AD-connected state, and a banner confirms that AD sync resumed. You don’t need to reconfigure the sync; choose Retry failed steps when you’re ready to try again.

Important: In both cases, choose Retry failed steps on the Confirm change screen. If you navigate away from this screen, you can no longer retry the failed steps and will need to restart the identity source change.

For troubleshooting tips, see Troubleshooting IAM Identity Center issues.

If you have feedback about this post, submit comments in the Comments section below.


Conclusion

This post covered how to migrate your IAM Identity Center identity source from Active Directory to an external identity provider (Okta), including backing up existing assignments, validating your target identity source, performing the cutover, verifying that the new identity source took over your users and groups with their assignments intact, validating access, and rolling back if needed.

For the backup and restore scripts referenced in this guide, see the aws-samples GitHub repository. For more information about IAM Identity Center configuration and permission set management, visit the AWS Security Blog and the AWS IAM Identity Center documentation.

Xiaoxue Xu

Xiaoxue is a Solutions Architect for AWS based in Toronto. She primarily works with Financial Services customers to help secure their workload and design scalable solutions on the AWS Cloud.

Kanwar Bajwa

Kanwar is a Principal Technical Account Manager at AWS who works with customers to optimize their use of AWS services and achieve their business objectives.

Richard-Merritt

Richard Merritt

Richard is a Senior Delivery Consultant – DevOps who helps customers with their DevOps journeys and to harness the power of the AWS Cloud.

Taimur Ijlal

Taimur Ijlal

Taimur is a Senior Delivery Consultant – Security with AWS based in UK. He helps customers in their cloud security journeys and to grow using the power of AWS.

Author

Laura Reith

Laura is an Identity Solutions Architect at AWS, where she thrives on helping customers overcome security and identity challenges. In her free time, she enjoys wreck diving and traveling around the world.

Yee Fei Ooi

Yee Fei is a Solutions Architect supporting independent software vendor (ISV) customers in Singapore and is part of the Containers TFC. She enjoys helping her customers to grow their businesses and build solutions that automate, innovate, and improve efficiency.

Automate IAM Identity Center governance with continuous discovery and reporting

31 August 2026 at 19:18

AWS IAM Identity Center integrates with external identity provider (IdP) to provide customers with a centralized authentication and authorization solution for AWS resources across AWS Organizations. AWS continues to invest into IAM Identity Center with a growing number of AWS services that natively integrate with IAM Identity Center. As your AWS organization scales, maintaining visibility into who has access to which applications and enforcing governance policies across accounts and Regions becomes increasingly complex. Identity Center helps address this by centralizing authentication and authorization for AWS resources across your organization, integrating with your external identity provider and a growing number of AWS services. However, as adoption scales, tracking access assignments and enforcing governance policies consistently becomes its own challenge.

This blog post focuses on planning your integration between an identity provider and IAM Identity Center for managed applications in your organization. We also walk through deploying and using an automated Identity Center discovery and reporting sample solution to help answer the governance and security questions:

  1. Which users or groups have access to which AWS applications?
  2. Who last accessed a specific AWS application and when?
  3. Which users and groups are assigned to which IAM Identity Center applications across organization and AWS Regions?
  4. How can you quickly generate reports to assist with compliance audits or security reviews?

The sample solution will identify associated AWS applications and the corresponding user and group assignments for the IAM Identity Center instances within your organization. The output is stored in a queryable format and generates CSV files for downstream analysis or reporting.

Plan identity governance for Identity Center application assignments

There are four key areas to start on when planning how to manage delegation and provisioning access across IAM Identity Center managed AWS applications. Bring together key stakeholders across security, governance, application, and business teams to make sure the implementation and integration will fit into the overall identity governance strategy.

  1. Who can provision managed AWS applications: You can implement the IAM restrictions for creation of new AWS resources within AWS accounts in your organization. For example, if you restrict provisioning into a production AWS account to only infrastructure as code (IaC) IAM roles, you would continue implementing restrictions using AWS identity policies, service control policies (SCP), resource control policies (RCP), or IaC policy evaluation tools like Open Policy Agent (OPA) or Checkov.
  2. Who manages user and group assignments: The managed application administrator handles authorization to managed applications within an AWS account. It’s recommended to clearly define roles and responsibilities across the workflow. You would have an IaC pipeline manage the integrated AWS resource provisioning with IAM Identity Center, then another workflow to allow requests to manage user and group membership for the managed application.
  3. How authentication flows from the IdP to AWS resources: Users will authenticate into Identity Center, then be authorized to access AWS managed applications. From there, they will be authorized to access the associated AWS service and resources tied to the managed application. Depending on the AWS service, the associated downstream resources might have their own IAM principals that the users can access.
  4. Mapping IdP identities to AWS resource access: There needs to be a link for workforce users and groups in your IdP, to Identity Center managed applications, and to downstream resources and permissions. Identifying the relationship will help you understand access within your AWS environment. Trusted identity propagation (TIP) is an additional feature of Identity Center that provides an end to end trail of the identity to the downstream service.

Create and manage an Identity Center application assignment lifeycle

As a security best practice, you should enable delegated administration when managing Identity Center within an AWS organization instances.

After you have IAM Identity Center set up within an organization instance, your member AWS accounts can start creating associated AWS resources. Within each member AWS account, the IAM principals that provision AWS resources will need two types of service-specific IAM permissions:

  • The first type of IAM permissions will be specific to the AWS service you want to provision. For example, to create an Amazon SageMaker AI domain, you would need the same IAM permissions to create the SageMaker AI domain and the downstream AWS resources SageMaker AI might use.
  • The second type of IAM permissions is specific to IAM Identity Center. The IAM principal used to create the resource, in this example SageMaker AI, will also need permissions to manage applications within the Identity Center instance.
{
	"Version": "2012-10-17",
	"Statement":
	[
		{
            "Effect": "Allow",
            "Action": [
                "sso:CreateManagedApplicationInstance",
                "sso:GetManagedApplicationInstance",
                "sso:DeleteManagedApplicationInstance",
                "sso:DescribeRegisteredRegions"
            ],
            "Resource": "*"
        },
        {
            "Effect": "Allow",
            "Action": [
                "sso:CreateApplication",
                "sso:DescribeApplication",
                "sso:DeleteApplication",
                "sso:PutApplicationGrant",
                "sso:PutApplicationAuthenticationMethod",
                "sso:PutApplicationAccessScope"
            ],
            "Resource": 
            [
                "arn:aws:sso::<INSERT-ACCOUNT-ID>:application/ssoins-<INSERT-INSTANCE-ID>/apl-*"
            ]
        }
    ]
}

IAM Identity Center application Amazon Resource Names (ARNs) follow a different standard naming convention that isn’t based on the original resource name that was provided during resource creation. For example, when a user creates an Amazon Simple Storage Service (Amazon S3) bucket and sets a specific bucket name, that bucket name is included in the ARN: arn:[partition]:s3:::[bucket-name]. Identity Center application ARNs use unique identifiers (GUIDs) generated at creation time.

Manage access for an Identity Center application

After the IAM Identity Center application is created, you will need to manage access to the Identity Center application and associated AWS resources. To continue with the SageMaker AI domain example, after the domain is created, an authorized IAM principal will need to assign Identity Center users or groups from the Identity Center instance to the domain. For Identity Center, you will need two types of Identity Center IAM permissions.

The first type of IAM permissions is used to list IAM Identity Center users and groups within the Identity Center instance. This is needed to read and select specific IAM users or groups to assign to an Identity Center application.

{
    "Version": "2012-10-17",
    "Statement":
    [
        {
            "Sid": "ListIdentityCenterUsers",
            "Effect": "Allow",
            "Action":
            [
                "identitystore:ListUsers",
                "identitystore:DescribeUser",
                "identitystore:ListGroups",
                "identitystore:DescribeGroup",
                "identitystore:ListGroupMemberships"
            ],
            "Resource": "*"
        }
    ]
}

Although IAM Identity Center users and groups have a GUID, the GUIDs aren’t clearly linked to the resource friendly names. For example, a group name could be Read-Only and the resource GUID could be 1234567890-abcdef12-3456-7890-abcd-ef1234567890 in the identity store. Additionally, the IAM actions to list users or groups require the AllUsers or AllGroups parameter. Because List actions require access to users and groups, a restrictive IAM policy can’t be used to prevent IAM principals from seeing a subset of users or groups within the identity store. The second type of IAM permission is used to create and manage application assignments for the Identity Center application within the Identity Center instance.

{
    "Version": "2012-10-17",
    "Statement":
    [
        {
            "Sid": "ManageApplicationAssignments",
            "Effect": "Allow",
            "Action": 
            [
                "sso:CreateApplicationAssignment",
                "sso:DeleteApplicationAssignment",
                "sso:ListApplicationAssignments",
                "sso:PutApplicationAssignmentConfiguration"
            ],
            "Resource":
            [
                "arn:aws:sso::<INSERT-ACCOUNT-ID>:application/ssoins-<INSERT-INSTANCE-ID>/apl-*"
            ]
        }
    ]
}

Because the IAM Identity Center application ARN is created using a unique application ID during creation, it’s not recommended to implement an IAM policy restricting authorized IAM principals to manage specific Identity Center applications. For example, to limit the application assignments to only a specific set of applications, you would need to:

  1. Create the AWS resource with IAM Identity Center as the authentication mechanism
  2. Query the Identity Center application ARN for the associated AWS resource
  3. Identify the IAM principal that will be used for application assignments
  4. Create or update an IAM policy associated to that IAM principal to allow application assignments for that specific application
  5. Create or update an SCP to restrict application assignment to that specific IAM principal

In lieu of implementing resource restrictions within identity policies, you should limit management of IAM Identity Center application and application assignments to a limited number of authorized IAM principals. In addition, it is recommended to implement detective and reactive capabilities to manage Identity Center application assignments.

Plan your naming conventions and automation strategy

IAM Identity Center provides several APIs to capture information about your AWS organization instances, applications, and assignments. Before implementing automation or guardrails, you should develop a methodical approach and understand what outcome you’re working backwards from. Start by defining naming conventions and deciding what parts of the workflow you want to centralize.

  1. Determine a naming convention for groups within your IdP: For example: AWS_<ACCT#>_<AWS_Service>_<LOB>_<ENV>_<AppName>. The IdP group name would look like: AWS_123412341234_SageMaker_Data_PROD_GTLabel.
  2. Define the naming convention for AWS resources for your Identity Center integrated applications: For example: <AWS_Service>_<LOB>_<AppName>. The AWS resource name would look like: SageMaker_Data_GTLabel.
  3. Define the naming convention for Identity Center application names: For example: <AWS_Service>_<LOB>_<ENV>_<AppName>. The Identity Center application name would look like: SageMaker_Data_PROD_GTLabel.
  4. Decide on the restrictions that you want to implement within your AWS environment. Depending on your enterprise’s security standard, you can implement specific restrictions based on mapping of a similar combination of ENV (environment), AWS service, LOB (line of business), or application name.
  5. Choose the portions of the application workflow that you want to centralize. This could include creating the application, making application assignments, or remediating issues.

As more configurations and permissions are centralized, additional overhead and bottlenecks can be introduced. It’s important to find the right balance for your enterprise. For example, if you centralize application assignments, each application team will need to submit a request to modify assignments that will be reviewed by a centralized team and could result in a delayed response. Conversely, if each application team handles their own assignments, there’s a risk that application assignments won’t align to enterprise security standards.

By understanding your goals and how you want to reach them, you can tailor the sample solution accordingly. Getting alignment on this requires planning and coordination across multiple teams within your organization. When thinking about more customized authorization logic—such as using provisioned AWS resource metadata—you should review how the specific AWS service integrates with IAM Identity Center managed applications. For example, if you want to find the Identity Center application ARN for a specific AWS resource, such as a SageMaker AI domain, use the following approach. A reverse lookup is necessary because AWS services create Identity Center applications with GUID-based ARNs that aren’t easily discoverable.

#!/bin/bash

DOMAIN_ID="d-xxxxxxxxxxxx"

REGION="xx-xxxx-x"

# Step 1: Get SageMaker domain details
echo "=== SageMaker Domain Details ==="
DOMAIN_INFO=$(aws sagemaker describe-domain \
--region $REGION \
--domain-id $DOMAIN_ID)

# Step 2: Extract Identity Center application ARN
SSO_APP_ARN=$(echo $DOMAIN_INFO | jq -r '.SingleSignOnApplicationArn')
echo "Identity Center App ARN: $SSO_APP_ARN"

IAM Identity Center automation sample solutions

The sample-iam-idc-application-discovery-reporting solution hosted on GitHub consists of two separate AWS CDK stacks:

  1. IAM Identity Center governance reporting stack (/identity-center-reporting directory) – Provides automated discovery and report generation (using CSV files)
  2. IAM Identity Center remediation stack (/identity-center-remediation directory) – Provides real-time enforcement and notifications

The recommendation is to deploy the reporting stack first to establish baseline visibility, then deploy the remediation stack for enforcement.

The following diagram depicts that IAM Identity Center governance architecture.

The reporting sample deploys the following resources:

  1. Amazon EventBridge – Rule invokes the discovery workflow daily at 2:00 AM UTC (configurable)
  2. AWS Step Functions – Orchestrates the multi-stage discovery workflow across instances, applications,and assignments
  3. AWS Lambda – Takes the following actions:
    1. Discovers IAM Identity Center instances across the organization and member accounts
    2. Application discovery that enumerates the applications configured in each Identity Center instance
    3. Assignment discovery maps users and groups to applications, resolving friendly names from the Identity Store
  4. Amazon DynamoDB – Stores the discovered instances, applications, and assignments, encrypted with an AWS Key Management Service (AWS KMS) customer-managed key
  5. Amazon API Gateway – Provides an IAM-authenticated REST API for a Lambda function to generate and export reports as CSV files
  6. Amazon S3 – Stores the encrypted CSV file exports, with lifecycle policies and time-limited Amazon S3 presigned download URLs

Deploy the IAM Identity Center reporting sample

The following procedure deploys the automated discovery and reporting infrastructure using AWS Cloud Development Kit (AWS CDK). Make sure you have the following prerequisites in place, then continue with the steps to set up the solution.

Prerequisites

You need to have the following to test the solution in this post.

  1. An AWS organization with an IAM Identity Center organization instance with delegated administrator access configured
  2. IAM Identity Center configured with at least one instance
  3. AWS Command Line Interface (AWS CLI) configured with appropriate credentials
  4. Python 3.12 & Node.js 18 or later installed for CDK deployment

To deploy the IAM Identity Center reporting solution, run the following commands:

  1. Clone the solution repository:
    git clone https://github.com/aws-samples/sample-iam-idc-application-discovery-reporting
    cd identity-center-reporting
  2. Install dependencies:
    python3.12 -m venv .venv && source .venv/bin/activate
    pip install -r requirements.txt
  3. Bootstrap the CDK (if not already done):
    cdk bootstrap aws://<INSERT-ACCOUNT-ID>/<INSERT-REGION>
  4. Deploy the sample solution:
    export IDC_EXTERNAL_ID="$(uuidgen)" # alternatively you can set this value — member-account roles need the same value
    
    cdk deploy --parameters AllowedIpRange=10.0.0.0/8 --parameters CrossAccountExternalId="$IDC_EXTERNAL_ID"

    Note: AllowedIPRange is optional but recommended as a security best practice. The parameter will add a network restriction to download the Amazon S3 presigned URL export.

  5. Optional: For AWS account-level Identity Center instance discovery, a cross-account IAM role is required.
    python scripts/deploy-cross-account-roles.py --external-id "$IDC_EXTERNAL_ID"
Figure 2: Successful AWS CDK deployment of the reporting stack

Figure 2: Successful AWS CDK deployment of the reporting stack

After the stack is successfully deployed, obtain the CDK output values for the API Gateway URL and S3 bucket name. If using a command line to deploy, these values will be displayed after the stack successfully deploys. It can also be found in the AWS Management Console as AWS CloudFormation stack output. The output will be used for generating reports in the following sections.

Note that this stack is for the reporting stack only. Reactive monitoring and deployment are described in the next section.

After the reporting stack is successfully deployed, the automation will run on a daily schedule. The first discovery run executes immediately after deployment. You can monitor discovery execution history and detailed logs through the the AWS Step Functions console. Review the detailed Lambda function logs in Amazon CloudWatch Logs. Query discovered instances, applications, and assignments through the DynamoDB console for one-time analysis.

Generate reports for Identity Center application assignments

To generate on-demand reports as CSV files from the REST API:

  1. Set env variables for Sigv4 authentication
      export AWS_REGION="<REPLACE-REGION>"
      export API_ID="<REPLACE-API-ID>"
      eval "$(aws configure export-credentials --profile "<YOUR-PROFILE>" --format env)"
  2. Export applications
      curl -sS --fail-with-body \
        --aws-sigv4 "aws:amz:${AWS_REGION}:execute-api" \
        --user "${AWS_ACCESS_KEY_ID}:${AWS_SECRET_ACCESS_KEY}" \
        --header "x-amz-security-token: ${AWS_SESSION_TOKEN}" \
        "https://${API_ID}.execute-api.${AWS_REGION}.amazonaws.com/prod/export/applications" \
        -o applications.json
  3. Export assignments with user and group names
      curl -sS --fail-with-body \
        --aws-sigv4 "aws:amz:${AWS_REGION}:execute-api" \
        --user "${AWS_ACCESS_KEY_ID}:${AWS_SECRET_ACCESS_KEY}" \
        --header "x-amz-security-token: ${AWS_SESSION_TOKEN}" \
        "https://${API_ID}.execute-api.${AWS_REGION}.amazonaws.com/prod/export/assignments" \
        -o assignments.json
  4. The API returns a JSON response with a presigned Amazon S3 URL that’s valid for 15 minutes:
    {
        "message": "CSV export generated successfully",
        "download_url": "https://<bucket>.s3.amazonaws.com/exports/applications/2026/06/22/applications_export_20260722_184538.csv?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Expires=900&...",
        "filename": "applications_export_20260722_184538.csv",
        "s3_key": "exports/applications/2026/07/22/applications_export_20260722_184538.csv",
        "file_size_bytes": 6514,
        "export_type": "applications",
        "generated_at": "2026-07-22T18:45:38Z",
        "expires_at": "2026-07-22T19:00:38Z",
        "request_id": "a1b2c3d4-...."
    }
    {
        "message": "CSV export generated successfully",
        "download_url": "https://<bucket>.s3.amazonaws.com/exports/applications/2026/07/22/applications_export_20260722_184538.csv?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Expires=900&...",
        "filename": "applications_export_20260722_184538.csv",
        "s3_key": "exports/applications/2026/07/22/applications_export_20260722_184538.csv",
        "file_size_bytes": 6514,
        "export_type": "applications",
        "generated_at": "2026-07-22T18:45:38Z",
        "expires_at": "2026-07-22T19:00:38Z",
        "request_id": "a1b2c3d4-...."
    }

The generated CSV files include enriched data with friendly names:

Instance ARN Account ID Application name Principal type Principal name Status
arn:aws:sso:::instance/… 123456789012 SageMaker_PROD GROUP Engineering-Team-Dev ACTIVE
arn:aws:sso:::instance/… 123456789012 OpenSearch_PROD USER jane.doe@example.com ACTIVE

You can use the generated CSV files to help identify anomalies or non-compliant assignments, such as:

  1. Each PROD application should only have GROUP assignments. OpenSearch_PROD has a USER principal type and so is non-compliant.
  2. Each PROD application should only allow PROD groups assigned. SageMaker_PROD has a DEV group name (Engineering-Team-Dev) assigned and so is non-compliant.

Based on the testing and analysis of the output from the IAM Identity Center governance reporting sample solution, it’s important to start thinking about what restrictions to put in place for application assignments. It’s also important to conduct this exercise before taking action within the Identity Center remediation sample solution in the next section.

IAM Identity Center remediation

The following diagram shows the IAM Identity Center remediation architecture.

The IAM Identity Center remediation sample solution deploys the following resources:

  1. Amazon EventBridge – Matches IAM Identity Center assignment and profile events from CloudTrail (sso.amazonaws.com) and invokes the monitor function across the following IAM actions:
    1. CreateApplicationAssignment
    2. DeleteApplicationAssignment
    3. PutApplicationAssignmentConfiguration
    4. AssociateProfile
    5. DisassociateProfile
    6. CreateProfile
    7. UpdateProfile
    8. DeleteProfile
  2. Lambda – Resolves the application and group names, validates the assignment against your naming convention, and notifies or remediates based on the configured mode
  3. Amazon Simple Notification Service (Amazon SNS) – Publishes alerts for non-compliant assignments to subscribers (for example, email)
  4. Amazon Simple Queue Service (Amazon SQS) – Captures events the Lambda function fails to process for later inspection
  5. AWS KMS – Customer-managed key to encrypt the Lambda environment variables, CloudWatch logs, SNS topic, and dead-letter queue
  6. Amazon CloudWatch – Log group stores the function’s structured, encrypted logs as an audit trail

Flexible naming policies support regex-based pattern matching for specific organizational requirements. The automation actions are logged to CloudWatch with structured JSON for additional analysis and reporting.

The following procedure deploys the remediation infrastructure using AWS Cloud Development Kit (AWS CDK). Make sure you have the following prerequisites in place, then continue with the steps to set up the solution.

Prerequisites

You need the following to run the remediation solution:

  1. An AWS organization with an IAM Identity Center organization instance with delegated administrator access configured
  2. IAM Identity Center configured with at least one instance and an IdP
  3. Access to create groups within the integrated IdP
  4. AWS Command Line Interface (AWS CLI) configured with appropriate credentials
  5. Python 3.12 & Node.js 18 or later installed for CDK deployment

Provide your IAM instance ARN and the account ID where IAM Identity Center is administered:

git clone https://github.com/aws-samples/sample-iam-idc-application-discovery-reporting # only needed if you did not clone in the previous reporting section
cd identity-center-remediation
cdk deploy --context enableAutoDeletion=false --parameters IdentityCenterInstanceArn=arn:aws:sso:::instance/ssoins-<INSERT-ORG-INSTANCE-ID> --parameters ManagementAccountId=<INSERT-MANAGEMENT-ACCOUNT>

Note: If you don’t pass a parameter for GroupNameRegex, the default action of the sample solution is to verify the group name appears as a whole word in the application name: Case-insensitive, splitting on -, _, and spaces, so ReadOnly matches sagemaker_readonly but read does not. If different validation is needed, the sample can be deployed with the regex value for GroupNameRegex.

After the solution is deployed, we will walk through testing both a compliant and non-compliant application assignment.

Gather Identity Center and application information

For this blog, we have already created two groups within the IdP that is integrated into an IAM Identity Center instance. We also already created two applications within Identity Center instance to use. Next, we’ll need to gather information specific to the environment to run through each example.

  1. Obtain the IAM Identity Center instance ARN and set the value.
    INSTANCE_ARN=$(aws sso-admin list-instances --region <REPLACE-REGION> --query "Instances[0].InstanceArn" --output text)
    
    echo "$INSTANCE_ARN"
  2. Obtain the IAM Identity Center identity store ID

    IDENTITY_STORE_ID=$(aws sso-admin list-instances --region <REPLACE-REGION> --query "Instances[0].IdentityStoreId" --output text)
    
    echo "$IDENTITY_STORE_ID"
  3. Get existing groups in IAM Identity Center
    aws identitystore list-groups --identity-store-id $IDENTITY_STORE_ID --query "Groups[].{Name:DisplayName,Id:GroupId}" --output table
  4. Get existing enabled applications in IAM Identity Center
    aws sso-admin list-applications --instance-arn $INSTANCE_ARN --query "Applications[?Status=='ENABLED'].{Name:Name,ARN:ApplicationArn}" --output table

After you have the output for IAM Identity Center groups and applications, select two groups and one application that you want to test with. You will need to set additional variables for each group GUID and application ARN. In this example, I select the following two groups (ReadOnly and Developer) for testing and set the environment variables using export:

  1. Group #1 Name: ReadOnly
    export GRP_READONLY=abc12345-1234-1234-1234-abcdef123456
    export GRP_DEVELOPER=abc12345-1234-1234-1234-abcdef123457
    export APP_READONLY="arn:aws:sso::<INSERT-ACCOUNT-ID>:application/<INSERT-INSTANCE-ARN>/<INSERT-APPLICATION-ARN>"
    • Group #2 Name: Developer
    • Application Name: sagemaker_readonly

As part of this validation, the sample solution verifies the group name appears as a whole word in the application name: Case-insensitive, splitting on the -, _, characters and spaces, so ReadOnly matches sagemaker_readonly but read does not. For different use-cases, The GroupNameRegex parameter can be used during deployment.

Test compliant and non-compliant assignments

Run the following command to add the ReadOnly group assignment to the sagemaker_readonly application:

aws sso-admin create-application-assignment --application-arn $APP_READONLY --principal-id $GRP_READONLY --principal-type GROUP

The group assignment request meets the validation criteria because the application name sagemaker_readonly contains the group name ReadOnly. The output logs for this validation exist within the associated lambda function CloudWatch log group /aws/lambda/identity-center-app-monitor”.

In this example, the logs will show:

✓ COMPLIANT - Group name found in application name

applicationName="sagemaker_readonly” groupName="ReadOnly”

Remediation action determined: NONE

Run the following command to try to add the Developer group assignment to the sagemaker_readonly application:

aws sso-admin create-application-assignment --application-arn $APP_READONLY --principal-id $GRP_DEVELOPER --principal-type GROUP

The group assignment request doesn’t meet the validation criteria because the application name sagemaker_readonly doesn’t contain the group name Developer. The output logs for this validation exists within the associated lambda function CloudWatch log group /aws/lambda/identity-center-app-monitor. Note that the remediation action listed shows NOTIFICATION_ONLY, meaning it only sent a notification to the configured SNS topic and did not take action. If you want the group assignment to be deleted, the value should be set to enableAutoDeletion=true.

In this example, the logs will show:

✗ NON-COMPLIANT - Group name not found in application name

applicationName="sagemaker_readonly” groupName="Developer”

Remediation action determined: NOTIFICATION_ONLY

SNS notification sent successfully

The SNS message will look like:

{
	"eventType": "NON_COMPLIANT_ASSIGNMENT",
	"applicationName": "sagemaker_readonly",
	"groupName": "Developer",
    "action": "NOTIFICATION_ONLY",
    "status": "SUCCESS",
    "applicationArn": "arn:aws:sso::1234:application/ssoins-1234/apl-1234",
    "groupId": "abc12345-1234-1234-1234-abcdef123457",
    "initiatedBy": { 
    	"type": "AssumedRole", 
    	"arn": "arn:aws:sts::1234:assumed-role/.../you" 
	}
}

Scheduled reporting gives baseline visibility into IAM Identity Center managed applications. Event-driven monitoring can provide near real-time notification or enforcement. Together, these sample solutions can help align and scale Identity Center with your governance and security standards through both historical analysis and immediate response.

Clean up

For each deployed CDK stack, run the following commands in the AWS account where it was deployed.

To delete the remediation stack, run the following commands:

cd sample-iam-idc-application-discovery-reporting/identity-center-remediation
cdk destroy

To delete the reporting stack, run the following commands:

cd sample-iam-idc-application-discovery-reporting/identity-center-reporting
cdk destroy

IAM governance automation at scale

Achieving effective IAM Identity Center governance at scale requires moving beyond manual processes to automated, continuous monitoring and reporting. The following high-level steps can provide an Identity center governance framework:

  1. Deploy the sample automation with an IAM principal that has access in your delegated administrator account.
  2. Establish a baseline by running your first discovery and reviewing the generated reports.
  3. Configure naming policies to match your organization’s security conventions.
  4. Deploy the event-driven monitoring capabilities to enable real-time policy enforcement and automated response based on the security policies.
  5. Start in notification mode to establish a baseline before enabling auto-remediation.
  6. Integrate with your governance tools by connecting the API endpoints to your compliance dashboards or ITSM tools.
  7. Move to auto-remediation once you have validated policies are working as expected.

Conclusion

Managing AWS IAM Identity Center at scale doesn’t have to be a manual, time-consuming process. By implementing automated discovery and reporting combined with real-time event-driven monitoring, you can maintain continuous visibility into your organization’s identity and access landscape, respond immediately to policy violations, and enforce governance policies consistently across your organization. Automation reduces operational work, strengthens security, speeds up incident response, and maintains compliance. Start by deploying these solutions to gain visibility and enable real-time enforcement.

If you have feedback about this post, submit comments in the Comments section below. If you have questions about this post, start a new thread on AWS re:Post or contact AWS Support.


Author

Jonathan Nguyen

Jonathan is a Principal WWSO AI Security Solution Architect at AWS. He helps customers develop a comprehensive AI security strategy so they can deploy secure AI workloads at scale, integrate AI-powered security services, and defend against AI-powered threats.

Extend your data perimeter to the AWS Management Console with Private Access

28 August 2026 at 20:53

Organizations in regulated industries such as financial services, government, defense, and healthcare restrict their sensitive workloads to isolated network environments with no access to the public internet. Until now, customers could restrict AWS Management Console access to authorized AWS accounts and corporate networks, but the console itself required internet connectivity. This was creating tension between operational convenience and network security controls.

We’re happy to announce that AWS Management Console Private Access is now generally available with support for virtual private clouds (VPCs) without internet connectivity. Organizations in regulated industries that restrict workloads to isolated network environments can now route all traffic for supported service consoles—including authentication flows, static assets (JavaScript, CSS, images), console-only APIs, and AWS service API calls—through AWS PrivateLink VPC endpoints, eliminating the need for an internet gateway, NAT gateway, or any route to the public internet. This capability is available in all AWS commercial Regions for a select set of supported service consoles.

In 2023, we launched AWS Management Console Private Access, which you can use to connect to the console by routing console, sign-in, and service API calls through VPC endpoints. However, accessing the console required internet connectivity for static assets and console-only APIs. This meant security teams faced a choice: allow internet connectivity to use the console or deny console access to operators working in network-isolated environments.

With this launch, AWS Management Console Private Access addresses two common scenarios:

  • Console traffic over internet restricted networks: Traffic for supported service consoles now flows entirely through your VPC endpoints—no proxy allowlists to maintain, no TLS-intercepting proxies to operate, and no CLI-only workflows to accept as a compromise. The same path works seamlessly from Amazon WorkSpaces, Amazon Elastic Compute Cloud (Amazon EC2) instances, and on-premises networks connected through AWS Direct Connect or AWS Site-to-Site VPN. Combined with sign-in resource control policies (RCPs) and sign-in resource policies, you can ensure that console authentication only succeeds from expected networks—even if valid credentials are presented elsewhere, the session is denied. Teams that previously relied on restricted egress rules or manual domain allowlists now get full console access with the same network controls they already trust.
  • Data-exfiltration prevention: Private Access enables you to restrict which AWS accounts and organizational identities can use the AWS Management Console from within your VPC. This prevents access from personal accounts and from accounts outside your organization. Attach a VPC endpoint policy with an aws:ResourceOrgID condition, and console actions are automatically scoped to resources inside your organization. Sign-in RCPs add a second layer by ensuring authentication only succeeds from networks within your perimeter. Together, these controls prevent supported service consoles from being used to access resources in accounts outside your organization—such as personal accounts—without requiring complex network-layer workarounds.

In this post, you will learn how AWS Management Console Private Access works in environments without internet connectivity, and how to layer access controls using VPC endpoint policies and sign-in resource control policies (RCPs) to strengthen your data perimeter.

Solution overview

AWS Management Console Private Access and sign-in resource control policies are a natural extension of the service control policies (SCPs), resource control policies, and VPC endpoint policies you already use for API traffic; now applied to the console session itself. The same data perimeter controls for identity, resource, and network that protect your programmatic access now protect interactive browser sessions too.

Perimeter Control objective Policy construct Implementation Steps
Identity Only trusted identities can access my resources Sign-In RCPs and RBPs Restrict which principals can sign in to the console. Before authentication, signin:PrincipalArn is available for exemptions only. After authentication, RCPs restrict at the organization, account, or principal level (aws:PrincipalOrgID, aws:PrincipalAccount, aws:PrincipalArn); RBPs restrict at the account or principal level.
Identity Only trusted identities are allowed from my network Console VPC endpoint policy and Sign-In VPC endpoint policy Console endpoint: aws:PrincipalOrgID or aws:PrincipalAccount on signed-in identities. Sign-In endpoint: aws:ResourceOrgID or aws:ResourceAccount before authentication, principal and resource keys after authentication. Blocks sign-in to accounts outside your organization, such as personal accounts, from your network.
Resource My identities can access only trusted resources SCP Resource perimeter SCP with aws:ResourceOrgID follows your principals into every console session; each service API call the console makes on their behalf is denied if the target resource is outside your organization.
Resource Only trusted resources can be accessed from my network Console VPC endpoint policy and service VPC endpoint policies Console endpoint policy with aws:ResourceOrgID and aws:ResourceAccount scopes what the console can reach through your network.
Network My identities can access resources only from expected networks SCP Network perimeter SCPs that use aws:SourceVpc deny your principals’ service calls from outside expected networks. With Private Access, requests proxied by the console to supported services carry aws:SourceVpc set to the VPC hosting your Private Access endpoints. Direct browser requests carry VPC context only when the service has its own VPC endpoint, so configure endpoints for every service you use. AWS recommends conditioning on aws:SourceVpc rather than specific aws:SourceVpce values.
Network My resources can only be accessed from expected networks Sign-In RBPs and RCPs and network perimeter RCPs Sign-In policies deny console authentication from unexpected networks using aws:SourceIp, aws:SourceVpc, aws:SourceVpce, and aws:VpcSourceIp in both pre-authentication and post-authentication statements. Network perimeter RCPs apply the same network conditions to your data resources for any access path.

With this launch, Console Private Access routes browser traffic for supported service consoles through VPC endpoints, including:

  • Authentication flows – Sign-in, credential exchange, and session token requests
  • Static assets – JavaScript, CSS, and images that render the console UI
  • Service console API calls – The backend requests made when users interact with service consoles

How traffic flows from a workload in a private VPC through the three Private Access endpoints, with no path to the public internet (shown in Figure 1):

  1. The operator’s browser requests <region>.console.aws.amazon.com.
  2. The corporate DNS forwarder forwards the query to an Amazon Route 53 Resolver inbound endpoint configured within the VPC, which forwards the traffic to the console VPC endpoint.
  3. Browser traffic flows from on-premises through Direct Connect (or AWS Site-to-Site VPN) to the VPC, and the VPC endpoint routes traffic to the console service over the AWS private network.
  4. The console service redirects to the SignIn endpoint <region>.signin.aws.amazon.com to establish a browser session.
  5. The DNS now resolves to the SignIn VPC endpoint’s private IP addresses, and browser traffic flows to the SignIn service over the AWS private network.
  6. After entering credentials, the SignIn service evaluates VPC endpoint policies, in addition to resource-based policies (RBPs) and RCPs, then redirects back to the console.
  7. The console evaluates VPC endpoint policies, loads static content from the console API VPC endpoint, and enforces identity and resource restrictions when making calls to AWS service APIs.
  8. Users can now access the AWS Management Console over Private Access.
Figure 1: Network isolation architecture

Figure 1: Network isolation architecture

Deploy a pilot of AWS Management Console Private Access

This high-level walkthrough sets up AWS Management Console Private Access for a single AWS Region within one organizational unit (OU). We recommend rolling out incrementally; validate each step before you expand to additional Regions and OUs.

If you want to validate the mechanics of a Private Access deployment before you build out the full solution, the Getting started with a test environment guide walks you through a minimal configuration: a single VPC with the three Private Access endpoints and a permissive policy. This gives you a working setup to experiment with, independent of the deployment described in the rest of this post. To understand how sign-in policies can verify a user’s network location when they access the console, see Controlling console access with resource-based policies and resource control policies.

Prerequisites

You must have the following prerequisites:

Step 1: Baseline current console access

Before changing anything, use CloudTrail to map how your users access the console today. Search for eventName = ConsoleLogin over a representative window (we recommend 30 days) and review the sourceIPAddress, vpcEndpointId, and awsRegion fields. Identify which identity types are in use: root user, IAM user, SAML federation, and AWS IAM Identity Center. Decide which OU or account you will pilot with.

Note: A misconfigured sign-in policy can lock users out of the console. Avoid piloting in a production or shared account. Instead, use a dedicated test account and configure a break-glass principal (covered in Step 5) before enabling access enforcement.

Step 2: Create the Private Access VPC endpoints

In your chosen Region, create or identify a VPC to host the endpoints, then create three interface VPC endpoints in that VPC:

  • com.amazonaws.<region>.console for the console.
  • com.amazonaws.<region>.signin for AWS Sign-In.
  • com.amazonaws.<region>.console-static for console-only APIs. This endpoint is required only if your VPC has no internet path.

Step 3: Configure private DNS for AWS Management Console Private Access

To use AWS Management Console Private Access, you must configure private DNS so that the console domains—.console.aws.amazon.com, .signin.aws.amazon.com, and the associated static-content domains—resolve to your interface endpoints’ network interfaces within your VPC.

  • For workloads inside your VPC: If the workloads in your VPC use the default Amazon Route 53 Resolver, no additional DNS configuration is required. When you create each interface endpoint, enable the private DNS name option (set PrivateDnsEnabled = true). The public console domains will then resolve automatically to the endpoint network interfaces inside your VPC. If you use a custom DNS resolver or a private hosted zone, you must configure it explicitly to map the console domains to the endpoint addresses. See Working with private hosted zones for more information. For the complete list of domains and detailed DNS configuration steps, see the AWS Management Console Private Access required endpoints documentation.
  • For workloads outside your VPC: For workloads that reach the endpoints from outside the VPC—such as corporate offices connecting over AWS Direct Connect or AWS Site-to-Site VPN—ensure that your corporate DNS resolver returns the endpoint addresses for these domains. See Simplify DNS management in a multi-account environment with Route 53 Resolver for more information.

Step 4: Verify private connectivity

Sign in to the console from a workload inside your VPC. The console should load normally. To confirm that traffic is routing through your VPC endpoints, look for the lock icon in the console navigation bar, shown in Figure 2.

Figure 2: Console Private Access

Figure 2: Console Private Access

You can also verify in CloudTrail that recent ConsoleLogin events show the vpcEndpointId field populated with one of your endpoint IDs. Here’s an example CloudTrail ConsoleLogin event snippet showing the vpcEndpointId field:

{
  "eventVersion": "1.08",
  "userIdentity": {
    "type": "AssumedRole",
    "principalId": "AROA3XFRBF23EXAMPLE:john.doe",
    "arn": "arn:aws:sts::123456789012:assumed-role/Admin/john.doe",
    "accountId": "123456789012"
  },
  "eventTime": "2026-07-08T19:15:32Z",
  "eventSource": "signin.amazonaws.com",
  "eventName": "ConsoleLogin",
  "awsRegion": "us-east-1",
  "sourceIPAddress": "10.0.1.47",
  "userAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7)...",
  "requestParameters": null,
  "responseElements": {
    "ConsoleLogin": "Success"
  },
  "additionalEventData": {
    "LoginTo": "https://console.aws.amazon.com/console/home",
    "MobileVersion": "No",
    "MFAUsed": "Yes",
    "vpcEndpointId": "vpce-0abc123def456789a"
  },
  "eventID": "a1b2c3d4-5678-90ab-cdef-EXAMPLE11111",
  "eventType": "AwsConsoleSignIn",
  "recipientAccountId": "123456789012"
}

If the AWS Management Console doesn’t load, work through the following checks.

Private DNS is enabled on each interface endpoint (or your custom resolver returns the endpoint addresses)

When Private DNS is enabled, AWS automatically creates the DNS entries that resolve the service domains (such as console.aws.amazon.com) to the private IP addresses of your VPC endpoints. Without it, your browser still routes to the public AWS endpoints, bypassing your private access setup entirely.

  1. Confirm that each endpoint shows PrivateDnsEnabled:
    aws ec2 describe-vpc-endpoints \
    --filters "Name=vpc-endpoint-type,Values=Interface" \
    --query "VpcEndpoints[].{Id:VpcEndpointId,Service:ServiceName,PrivateDns:PrivateDnsEnabled}" \
    --output table
    
  2. Then, from within your VPC, verify that the domains resolve to private addresses:
    nslookup console.aws.amazon.com
    nslookup signin.aws.amazon.com
    
    # Should return a private IP (e.g., 10.x.x.x), not a public one
    

Each query should return a private IP address from your VPC CIDR range. If you use a custom DNS resolver instead of the Amazon-provided DNS, ensure your forwarding rules direct the AWS domain queries to the Route 53 Resolver inbound endpoints in your VPC.

The endpoint security groups allow HTTPS (TCP 443) from your workload subnets

Each VPC endpoint creates elastic network interfaces (ENIs) in your subnets, and these ENIs are governed by security groups. If those security groups don’t permit inbound HTTPS traffic from your workloads, the connection fails silently.

  1. Identify the security groups attached to your endpoints:
    aws ec2 describe-vpc-endpoints --vpc-endpoint-ids vpce-0abc123def456789a \
      --query "VpcEndpoints[].Groups[].GroupId" --output text
    
  2. Then verify that each security group allows inbound TCP 443 from your workload subnets:
    aws ec2 describe-security-groups --group-ids sg-xxxxxxxx \
      --query "SecurityGroups[].IpPermissions[?ToPort==\`443\`]" \
      --output json
    

For traffic from outside the VPC (Direct Connect or Site-to-Site VPN), corporate DNS returns the endpoint IPs and the route propagates correctly

If you access the console from an on-premises workstation connected over AWS Direct Connect or AWS Site-to-Site VPN, two additional conditions must be met.

  1. Your corporate DNS must resolve the AWS domains to the VPC endpoint private IPs. From your on-premises machine, run:

    nslookup console.aws.amazon.com

    If this returns public AWS IPs, your corporate DNS isn’t forwarding queries through Route 53 Resolver. Configure conditional forwarding for the aws.amazon.com and amazonaws.com domains to your Resolver inbound endpoint IPs.

  2. Second, network routes must propagate correctly. Ensure the route table associated with your endpoint subnets has propagated routes from your virtual private gateway (VGW) or transit gateway, so return traffic can reach your on-premises network. Verify this with:
    aws ec2 describe-route-tables \
      --filters "Name=association.subnet-id,Values=subnet-xxxxx" \
      --query "RouteTables[].PropagatingVgws"
    

A quick end-to-end validation: Run traceroute console.aws.amazon.com from your workstation and confirm the path uses private hops only—no traffic should traverse the public internet.

If the console loads but the lock icon is missing

If the console loads but the connection isn’t private (for example, the lock icon is missing), the browser is reaching the console over the public internet instead of through your VPC endpoints.

  • Run nslookup console.aws.amazon.com from a workload inside the VPC. The result should be a private IP from your VPC CIDR range. A public IP means DNS is bypassing the endpoint, which usually happens because Private DNS has not been enabled on the interface endpoint (set PrivateDnsEnabled = true).
  • For workloads outside the VPC, make sure your corporate DNS forwards the console domains into the VPC, for example, through an Amazon Route 53 Resolver inbound endpoint.

Step 5: Apply VPC endpoint policies

Attach an endpoint policy to the console and AWS Sign-In endpoints that limits access to identities in your organization. The static-content endpoint doesn’t support endpoint policies.

Begin with a permissive Allow * policy and confirm that traffic routes through the endpoints (you should see the vpcEndpointId field populated in CloudTrail console events). After confirming the routing, add restrictions to your VPC endpoint policy and observe the traffic.

A starter policy uses two condition keys: aws:PrincipalOrgID to restrict identities to your organization and aws:ResourceOrgID to restrict the resources the console can reach to your organization’s resources. The full reference, including additional condition keys and resource-restriction patterns, is in the AWS Management Console Private Access user guide.

For policies beyond the pilot, see Data perimeters on AWS. The data perimeter policy examples GitHub repository covers service-specific considerations for implementing data perimeters in your environment.

Step 6: Apply a Sign-In policy

Sign-In policies deny console authentication requests that don’t match your network or principal conditions. The policy is composed of a pre-authentication statement covering signin:Authenticate and a post-authentication statement covering signin:AuthorizeOAuth2Access and signin:CreateOAuth2Token. Include both statements.

For your pilot, deploy the policy as an RCP from your AWS Organizations management account. When enabled, the RCP applies to all accounts in your organization, so we recommend piloting in a dedicated test organization before rolling it out broadly. Activate enforcement by calling the signin:PutConsoleAuthorizationConfiguration API for the organization in the us-east-1 Region (AWS Sign-In replicates policies globally from there). Resource permission statements have no effect until console authorization is enabled.

Important: Configure at least one excluded principal as a break-glass path before you enable the RCP. The recommended principal is a dedicated IAM role.

  1. Write the permission statements that define the network conditions:
    Example – Restrict access to corporate VPC:

    aws signin put-resource-permission-statement \
      --source-vpc vpc-0abc123def456789 \
      --requested-region us-west-2 \
      --excluded-principal "arn:aws:iam::123456789012:user/EmergencyAdmin" \
      --region us-east-1
    

    Example – Restrict access to specific IP range:

    aws signin put-resource-permission-statement \
      --source-ip "IP_ADDRESS" \
      --excluded-principal "arn:aws:iam::123456789012:role/BreakGlassRole" \
      --region us-east-1
    
  2. Enable console authorization for the organization to start enforcing the policy.
    aws signin put-console-authorization-configuration \
      --target-id <your-target-id> \
      --region us-east-1
    
  3. Review the consolidated policy that’s now in effect: 
    aws signin get-resource-policy --region us-east-1
    

For policy examples, the AWS Command Line Interface (AWS CLI) reference, and the lockout-recovery procedure, see the sign-in RBP blog post and the Controlling console access with resource-based policies documentation. The same documentation also covers the per-account alternative, which uses an RBP attached to a single account instead of an organization-wide RCP.

Step 7: Add a service VPC endpoint

So far, the console shell loads, the lock icon appears, and your Sign-In policy lets approved identities through. If you sign in to a service console such as the AWS Key Management Service (AWS KMS) console, the page might fail to load resources or hang. The Private Access endpoints carry the console shell, not the service API calls that the console makes on your behalf. In a VPC without an internet gateway, those calls have nowhere to go.

Add a VPC endpoint for the service itself. For the pilot, create an AWS KMS interface endpoint (com.amazonaws.<region>.kms) in the same VPC, with Private DNS enabled. Open the AWS KMS console from inside the VPC and confirm the list of keys loads. Repeat for each service your users need on day one. Please note that a single service console often calls more than one AWS service API. If a console loads but parts of the page show errors or stay empty, the most common cause is a missing endpoint for one of the services it depends on.

The current list of services that support PrivateLink is in the AWS PrivateLink documentation. Service consoles whose services don’t support PrivateLink will not work in a no-internet VPC and need to be handled separately.

Step 8: Hide Regions and services you haven’t configured (optional)

Console links to a service or Region that you don’t have endpoints for will fail inside your VPC. To prevent users from navigating to broken pages, use User Experience Customization (UXC) to hide Regions and services that aren’t part of your Private Access deployment. UXC is configured at the account level and applies to navigation, search results, and service-selection drop-downs.

Step 9: Validate, then expand

After applying the endpoint policies and the Sign-In RCP to one pilot account:

  1. Sign in from inside the corporate network. The session should succeed.
  2. Sign in from outside the corporate network. The session should be denied at the Sign-In step, before reaching the console.
  3. In CloudTrail, confirm ConsoleLogin events show vpcEndpointId populated for traffic from inside the network.
  4. For unexpected denials, look in CloudTrail for ConsoleLogin events with the error message Authorization denied because of a resource-based policy or Authorization denied because of a resource control policy to identify which statement was responsible.

Considerations

A few items worth mentioning before you commit to this design:

  • AWS IAM Identity Center: IAM Identity Center sign-in support isn’t yet available through a VPC endpoint. Initial single sign-on (SSO) authentication must still transit over the internet.
  • Programmatic access: Sign-In RBPs and RCPs gate interactive console sign-in. AWS SDK and AWS CLI requests signed with SigV4 aren’t affected. This is also your recovery path: a principal with signin:DeleteConsoleAuthorizationConfiguration permission can disable enforcement programmatically if console authorization is misconfigured.
  • Apps integrated with AWS Sign-In: Sign-In policies also apply to Amazon Connect, Amazon WorkSpaces, Amazon QuickSight, AWS Health Dashboard, Amazon AppStream 2.0, and Amazon Lightsail when those applications use AWS Sign-In to authenticate.
  • AWS Management Console Private Access is available in all commercial AWS Regions but supports only a subset of AWS service consoles. See Supported AWS Regions, service consoles, and features in Private Access documentation for more information.
  • For services that aren’t supported, you can still navigate to other consoles, but will require internet connectivity for the unsupported service consoles and console-only APIs.
  • Costs: You pay regular AWS PrivateLink endpoint pricing and data processing for each endpoint and each Region you deploy in. The three Private Access endpoints (console, signin, and console-static) plus the service endpoints you already use are the relevant line items.

Conclusion

In this post, we showed you how to extend the AWS data perimeter framework to the AWS Management Console. You routed console traffic through VPC endpoints with AWS Management Console Private Access, restricted console sign-in by network and organization with Sign-In RBPs and RCPs, and configured the console to operate in a VPC without an internet gateway. The four control objectives that you already enforce for API traffic now also apply to the console.

To get started, see the AWS Management Console Private Access documentation. For deployment patterns and Region-by-Region considerations, see the AWS Management Console Private Access reference architectures. For background on the broader pattern, see Establishing a data perimeter on AWS.

If you have feedback about this post, submit comments in the Comments section below. If you have questions about this post, start a new thread on the IAM forum on AWS re:Post or contact AWS Support.


Madhur Kulkarni

Madhur Kulkarni

Madhur is a Sr. Customer Solutions Manager at AWS, working with Strategic Accounts customers to accelerate cloud adoption and drive business outcomes. He partners with cross-functional teams across customer engineering, AWS service teams, and specialists organizations to deliver enterprise-scale cloud solutions.

Mateusz Jaworski

Mateusz Jaworski

Mateusz is a Principal Engineer at AWS, where he works on AWS Management Console.

Sujay Ghosh

Sujay Ghosh

Sujay is a Software Development Manager at AWS, where he leads a team responsible for enabling secure, reliable access to the AWS Management Console. He is passionate about building scalable infrastructure that helps millions of customers manage their cloud resources safely and efficiently.

Abhijit Barde

Abhijit Barde

Abhijit is a Principal Product Manager at AWS, where he focuses on making it straightforward for all AWS users to discover, monitor, and operate their AWS infrastructure using conversational assistants and generative AI.

Detecting multi-stage attacks on AWS: A guide to cross-service signal correlation

26 August 2026 at 19:39

A single alert from one security service tells you something happened. Read that signal alongside activity from other services and your own business context, and you will know whether what happened is part of a multi-stage attack.

Consider a short sequence. An identity calls GetCallerIdentity from a source address it hasn’t previously used. Within minutes, that same identity runs a burst of List and Describe calls across several services, and some of them fail with AccessDenied. Soon after, a large volume of data leaves your environment toward a domain that was registered last week. Amazon GuardDuty might already flag pieces of this, such as the reconnaissance from an unfamiliar source, through finding types like Recon:IAMUser/* or Discovery:S3/*. What you gain from correlating the pieces yourself is a single view of the sequence, tied to your own business context, so you can act on the whole rather than triaging findings one at a time.

This post is for security engineers and security operations teams who run Amazon Web Services (AWS) detection services and want to catch patterns specific to their environment. You will see how AWS detection and your business context fit together, and how to build correlations that use that context. The examples run in Amazon CloudWatch Logs Insights so you can try them today, and the closing section describes how to grow them into an automated pipeline. The walkthrough later in this post lists the prerequisites for these queries.

Start with AWS detection services

Begin with the AWS detection services. They cover the threats common across customers, and everything in this post is built on them.

Turn these on and tune them before you build anything custom. Tuning means adjusting sensitivity to reduce false positives for your environment, choosing which data sources each service monitors, and suppressing findings for known-good patterns.

GuardDuty correlates multi-stage attacks for you

Before you build anything by hand, see what GuardDuty already does for you. Amazon GuardDuty Extended Threat Detection correlates signals across multiple data sources including AWS CloudTrail, Amazon S3 data events, runtime monitoring, Amazon Elastic Kubernetes Service (Amazon EKS) audit logs, and more, then raises a single critical severity attack sequence finding when it spots a multi-stage pattern. It recognizes sequences such as credential compromise followed by data exfiltration, maps them to MITRE ATT&CK tactics, and attaches a timeline and remediation guidance. If you have GuardDuty enabled today, then GuardDuty Extended Threat Detection is already enabled by default and needs no queries from you. For details on how GuardDuty charges apply, see Amazon GuardDuty pricing.

The credential compromise sequence in the opening example is the kind of universal pattern GuardDuty Extended Threat Detection is built to catch, so rely on it for those. Attack sequence findings show up in the GuardDuty console next to your other findings, and they route to Security Hub and your response workflows the same way.

GuardDuty handles the threats that look the same in every account. What it doesn’t have is the context that makes a given action suspicious in your account. That’s what you provide.

Add your business context

Business context is what only you know about your environment: which buckets hold sensitive data, which principals have a reason to touch which resources, which role chains your policy permits, and when your production change windows open. GuardDuty Extended Threat Detection learns from patterns common across customers, but it can’t answer these environment-specific questions. Express them as correlations and you add a detection layer tuned to your environment. Each of the following four patterns turns one of these facts into a query.

Run these queries in the AWS Management Console for CloudWatch by choosing Logs, then Logs Insights, using the CloudWatch Logs Insights query language. Most read CloudTrail events from a CloudWatch Logs log group that your trail delivers to. If your trail writes only to Amazon S3, add CloudWatch Logs delivery on the trail, or run equivalent queries in Amazon Athena (a serverless query service for analyzing data in Amazon S3 using SQL).

Note: The queries and code in this post use placeholder values. Replace them with your own before running: your-sensitive-bucket (your S3 bucket name), your-key-id (your AWS KMS key ID), region (your AWS Region, such as us-east-1), account-id (your 12-digit AWS account ID), and aws-cloudtrail-logs-my-trail (your CloudTrail log group name).

A note on multi-account environments. In AWS Organizations, an organization trail delivers every account’s events to one log group, so these queries work as-is but return cross-account results. Filter by recipientAccountId for account-scoped views. Without an organization trail, run queries per account or use Amazon Security Lake as a central query surface.

The attack chain mapped to AWS services

Multi-stage attacks move through five phases, and each phase leaves a signal in a different service. These signals surface across three log sources: CloudTrail, which records API activity in your account; Amazon VPC Flow Logs, which capture network connection metadata; and Amazon Route 53 Resolver query logs, which record DNS queries from your VPCs.

  • Initial access – Stolen credentials reach your environment. CloudTrail records GetCallerIdentity, GetSessionToken, or AssumeRole from an unfamiliar source.
  • Discovery – The threat actor enumerates with List, Describe, and Get calls, often triggering AccessDenied responses.
  • Privilege escalation – The threat actor chains roles or edits policies. CloudTrail records AssumeRole sequences, PutRolePolicy, or CreateAccessKey.
  • Lateral movement – The threat actor moves across accounts or AWS Regions, assuming roles and creating resources in unfamiliar places.
  • Exfiltration – Data leaves through GetObject calls at scale, large outbound transfers in VPC Flow Logs, and DNS queries in Route 53 Resolver query logs to recently registered domains.

Figure 1 shows the five attack phases mapped to the AWS log source that records each one.

Figure 1: Attack chain mapped to AWS services

Figure 1: Attack chain mapped to AWS services

GuardDuty Extended Threat Detection watches this chain for universal patterns. The four patterns that follow add the dimension you supply: your business context.

Pattern one: Sensitive data access by an unexpected principal

Your data classification and access norms drive this detection. One bucket holds customer records, another holds public web assets, and you know which principals have a reason to read the customer records, which are sensitive. Encode that knowledge and an ordinary looking read turns into something worth chasing.

Three signals converge here. CloudTrail shows GetObject at volume on a bucket you’ve classified as sensitive. The principal isn’t on your list of expected readers for that bucket. And VPC Flow Logs show a large outbound transfer from the same source in the same window, while DNS query logs show a recently registered destination domain, which together increase your confidence that there’s a potential threat.

CloudTrail management events don’t record GetObject. You must turn on CloudTrail data events for the buckets you care about to capture GetObject. Many teams miss GetObject because data events weren’t enabled on the relevant buckets.

This query shows bulk reads on a sensitive bucket, grouped by principal. Run it in CloudWatch Logs Insights with your CloudTrail log group selected.

fields @timestamp, userIdentity.arn, requestParameters.bucketName
| filter eventSource = "s3.amazonaws.com" and eventName = "GetObject"
| filter requestParameters.bucketName = "your-sensitive-bucket"
| stats count(*) as objectReads,
        count_distinct(requestParameters.key) as distinctObjects
        by userIdentity.arn, bin(10m)
| filter objectReads > 100
| sort objectReads desc

The threshold of 100 is a placeholder. Run the query over a week of normal activity, find the ninety-fifth percentile read count for that bucket, and set the threshold above it. Then check each principal the query returns against your expected reader list. A principal that isn’t on the list, reading at volume, is the result to investigate.

To corroborate, look for a matching outbound transfer. Switch the log group selector to your VPC Flow Logs log group and run this.

fields @timestamp, srcAddr, dstAddr, bytes
| filter action = "ACCEPT"
# exclude RFC 1918 private ranges so only external destinations remain
| filter dstAddr not like /^10\./
        and dstAddr not like /^192\.168\./
        and dstAddr not like /^172\.(1[6-9]|2[0-9]|3[0-1])\./
| stats sum(bytes) as totalBytes by srcAddr, dstAddr, bin(10m)
| filter totalBytes > 1000000000
| sort totalBytes desc

The Amazon S3 query returns a principal, and the Flow Logs query works on IP addresses, so you translate one into the other. The worked example later in this post covers that translation in full.

Picture an analytics role that reads a reporting bucket all day. One afternoon, it reads a thousand objects from your customer records bucket instead. GuardDuty stays quiet, because an authenticated role making valid GetObject calls isn’t suspicious anywhere else. Your query flags it, because that role isn’t on the expected reader list for that bucket. The classification you applied is what turns silence into a signal.

Figure 2 shows a bulk read from a sensitive bucket in CloudTrail, a large outbound transfer in VPC Flow Logs, and a young domain resolution in Route 53 Resolver logs.

Figure 2: Three signals converging within a single time window to indicate exfiltration

Figure 2: Three signals converging within a single time window to indicate exfiltration

Pattern two: A role chain that crosses your access policy

Picture a deployment that assumes one role to build, then a second to release. For one principal, that two-hop AssumeRole chain is routine; for a different principal it’s a policy violation. This pattern relies on your trust topology—the chains your organization permits—so put that knowledge in the query.

This pattern needs three conditions:

  • CloudTrail shows several AssumeRole calls from the same source inside a short window
  • The chain ends in a sensitive action such as CreateAccessKey, PutRolePolicy, or AttachUserPolicy
  • The starting identity isn’t one your policy expects to run that chain

In CloudWatch Logs Insights, select your CloudTrail log group and run this query, which surfaces chains of two or more hops.

fields @timestamp, userIdentity.arn, requestParameters.roleArn, sourceIPAddress
| filter eventName = "AssumeRole"
| stats count(*) as assumeCount,
        count_distinct(requestParameters.roleArn) as rolesAssumed
        by sourceIPAddress, bin(5m)
| filter assumeCount >= 2 and rolesAssumed >= 2
| sort assumeCount desc

Two hops is the minimum for a chain; raise the count if your environment chains roles often. Your deployment pipeline probably assumes several roles an hour, as do AWS service principals such as AWS Security Hub. Exclude the identities you expect to see assuming multiple roles, including your pipeline role and known AWS service principals. What’s left is the set to investigate, such as a person assuming several roles at an odd hour and ending in a new access key. Treat that distinction as data: list the identities and actions you consider normal, and review the chains that fall outside the list.

Pattern three: An encryption key used outside its owning workload

Resource ownership is the signal here. A given AWS Key Management Service (AWS KMS) key creates and controls the encryption keys for a workload, and a single key should serve a single workload, such as a payments service. A Decrypt call against it is a valid, authorized API action, so nothing about the call itself looks wrong. The ownership rule you set is what makes another principal’s use of the key worth a second look.

This pattern applies only to customer-managed keys scoped to one workload. It doesn’t apply to AWS-managed keys (alias/aws/*) or to customer-managed keys intentionally shared across services. Confirm single-workload intent from the key policy’s Principal block before deploying this rule.

Two conditions indicate misuse:

  • CloudTrail shows Decrypt or GenerateDataKey calls on a key that’s tied to one workload
  • The calling principal isn’t the role that owns that workload

Against your CloudTrail log group, run this query to list the principals that called a specific key.

fields @timestamp, userIdentity.arn, eventName
| filter eventSource = "kms.amazonaws.com"
| filter eventName in ["Decrypt", "GenerateDataKey", "Encrypt"]
| filter resources.0.ARN = "arn:aws:kms:region:account-id:key/your-key-id"
| stats count(*) as keyUses by userIdentity.arn, eventName
| sort keyUses desc

Compare what comes back against the one workload role you expect. A principal you don’t recognize on that key is the signal. Because key misuse is an early move in data theft, this correlation catches activity that only your ownership knowledge can flag.

Consider a key that wraps your payments database. The payments service role calls it in normal operation, and nothing else should. If a developer role or a freshly created role runs Decrypt against it, the call succeeds and reads as ordinary in isolation. The reason it matters is the ownership rule you hold in your head and now state in this query.

Pattern four: A privileged action outside your change window

Start with the query, then read what it means.

fields @timestamp, userIdentity.arn, eventName, sourceIPAddress
| filter eventName in ["PutRolePolicy", "AttachRolePolicy",
        "CreateAccessKey", "AuthorizeSecurityGroupIngress", "PutBucketPolicy"]
| stats count(*) as sensitiveChanges by userIdentity.arn, eventName, sourceIPAddress
| sort sensitiveChanges desc

Run it against your CloudTrail log group, scoped to your off-hours window when you schedule it, so it returns only activity outside the change window. Your change process defines what normal looks like here: production security and identity changes flow through a pipeline during defined hours, run by a known actor. A console-driven policy change at 2:00 AM, made by a person rather than the pipeline, doesn’t fit those expectations. The signal is a sensitive change such as PutRolePolicy or AuthorizeSecurityGroupIngress, made outside the window, by a person rather than your pipeline role.

Exclude the actors you expect, such as your deployment pipeline role, your patch automation role, and AWS service principals like AWS CloudFormation and AWS Systems Manager. What remains is privileged change made outside your process, which is both what an attacker does to establish persistence and what your own change discipline says shouldn’t happen.

Your pipeline might open security group rules during a deployment every weekday afternoon. A person opening a security group rule at midnight on a weekend is the same API call carrying a very different meaning. The schedule and the actor, both facts you define, are what separate the two.

Build your first correlation rule

The following walkthrough uses pattern one as a complete example. The other three patterns follow the same design with their own queries.

Prerequisites

These prerequisites feed the queries in this walkthrough. Confirm each one before you start:

  • A CloudTrail trail logging management events to a CloudWatch Logs log group
  • CloudTrail data events enabled for your sensitive S3 buckets
  • GuardDuty enabled, with its protection plans and Extended Threat Detection
  • VPC Flow Logs on for your production VPCs
  • Amazon Route 53 Resolver query logging on

CloudTrail, GuardDuty, VPC Flow Logs, and Route 53 Resolver query logging provide the raw signals that your correlations connect. Without them, the queries in this post return empty results.

Step 1: Record the bucket and its expected readers

Choose one sensitive bucket to monitor, and write down the principals allowed to read it. Store the list where your automation can reach it, such as a configuration file in version control or an Amazon DynamoDB table (a managed NoSQL database).

{
  "customer-records-prod": [
    "arn:aws:iam::123456789012:role/AnalyticsPipeline",
    "arn:aws:iam::123456789012:role/ComplianceAudit"
  ],
  "financial-data-archive": [
    "arn:aws:iam::123456789012:role/FinanceReporting"
  ]
}

This example hardcodes the list for simplicity. In production, load it from a DynamoDB table or Parameter Store so you can update it without redeploying.

Step 2: Baseline before you set a threshold

Run the pattern one query over one week of normal activity. Find the 95th percentile read count for the bucket and use a value greater than that as your alert threshold. This step keeps legitimate high-volume access from generating false positives later.

Set the THRESHOLD_READS environment variable to this value when you configure the function in Step 5.

Step 3: Run the access query

In the CloudWatch console:

  1. Choose Logs, then choose Logs Insights.
  2. In the Select log group(s) dropdown, select your CloudTrail log group.
  3. Set the time range to 3h (the last three hours).
  4. In the query editor, paste the pattern one query.
  5. Replace your-sensitive-bucket with your bucket name.
  6. Choose Run query.
  7. Review the principals in the results table.
  8. Compare each principal against your expected reader list from step 1, and flag any that are not on it.

Each result includes a principal that step 4 translates into an IP address.

Step 4: Correlate with network activity

CloudTrail logs actions by AWS Identity and Access Management (IAM) principal, while VPC Flow Logs record traffic by IP address. To connect the two signals, translate the principal into its address.

For a role attached to an Amazon Elastic Compute Cloud (Amazon EC2) instance, the userIdentity.principalId field includes the instance ID after the colon, in the form AROAEXAMPLE:i-1234567890abcdef0. Copy the instance ID and look up its private IP address.

aws ec2 describe-instances \
  --instance-ids i-1234567890abcdef0 \
  --query "Reservations[0].Instances[0].PrivateIpAddress" \
  --output text

Other compute types differ. A VPC-connected AWS Lambda function sends traffic through elastic network interfaces in your subnets, so correlate on those interface addresses. An Amazon Elastic Container Service (Amazon ECS) task records its network interface in task metadata. For a plain assumed-role session with no instance behind it, the sourceIPAddress field in CloudTrail already holds the caller’s address, so you correlate on it directly.

Run the Flow Logs query from pattern one, filtering srcAddr to that address within 10 minutes of the Amazon S3 read timestamp. A match places the same source behind both the sensitive read and a large external transfer in one window. CloudTrail events reach CloudWatch Logs 5–15 minutes after the API call, so correlate on eventTime rather than query time. Query a wider lookback than your correlation window: for example, look back 30 to 60 minutes but correlate on a 10-minute eventTime window. Steps 3 and 4 are manual validation; step 5 automates them.

Figure 2 shows DNS resolution as a third corroborating signal. This walkthrough implements the CloudTrail and VPC Flow Logs correlation. To add DNS, apply the same run_query() pattern against your Route 53 Resolver query log group.

Step 5: Automate the check

Move the query into a Lambda function (serverless compute that runs your code without a server to manage), send results to a notification channel, and schedule regular runs. Work through the following sub-procedures.

To create the notification channel

  1. Open the Amazon Simple Notification Service (Amazon SNS) console. Amazon SNS is a managed messaging service that delivers notifications to subscribers.
  2. In the navigation pane, choose Topics.
  3. Choose Create topic.
  4. For Type, select Standard.
  5. For Name, enter security-correlation-alerts.
  6. Choose Create topic.
  7. Note the topic Amazon Resource Name (ARN) at the top of the topic details page. You will use it in the function.
  8. Choose Create subscription.
  9. For Protocol, select Email.
  10. For Endpoint, enter your email address or incident management endpoint.
  11. Choose Create subscription, then confirm the subscription from the email AWS sends.

To create the EventBridge Scheduler execution role

The schedule needs a role that lets it invoke your function, and its trust policy needs conditions that pin the role to the schedule you own. Without those conditions, another account with access to the scheduler service could theoretically call this role; a class of misuse known as the confused deputy problem.

1. Create a trust policy file named scheduler-trust-policy.json.

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": { "Service": "scheduler.amazonaws.com" },
      "Action": "sts:AssumeRole",
      "Condition": {
        "StringEquals": {
          "aws:SourceAccount": "ACCOUNT-ID"
        },
        "ArnLike": {
          "aws:SourceArn": "arn:aws:scheduler:REGION:ACCOUNT-ID:schedule/*/s3-access-correlation-hourly"
        }
      }
    }
  ]
}

2. Create the role, then attach permission to invoke the function. Scope Resource to the specific function ARN so this role can’t invoke anything else.

aws iam create-role \
  --role-name EventBridgeSchedulerRole \
  --assume-role-policy-document file://scheduler-trust-policy.json

aws iam put-role-policy \
  --role-name EventBridgeSchedulerRole \
  --policy-name LambdaInvokePolicy \
  --policy-document '{
    "Version": "2012-10-17",
    "Statement": [
      {
        "Effect": "Allow",
        "Action": "lambda:InvokeFunction",
        "Resource": "arn:aws:lambda:REGION:ACCOUNT-ID:function:CorrelationFunction"
      }
    ]
  }'

When you create the function, Lambda automatically creates an execution role. You will attach the permissions this function needs to that role in a later step.

To deploy the correlation function

  1. Open the Lambda console.
  2. Choose Create function.
  3. For Function name, enter CorrelationFunction.
  4. For Runtime, select the latest Python runtime.
  5. Choose Create function.
  6. On the Code tab, replace the default code with the following function, then choose Deploy.
import os
import time
import logging
import boto3
from botocore.exceptions import ClientError

logger = logging.getLogger()
logger.setLevel(logging.INFO)

logs = boto3.client("logs")
sns = boto3.client("sns")
ec2 = boto3.client("ec2")

CLOUDTRAIL_LOG_GROUP = os.environ["CLOUDTRAIL_LOG_GROUP"]
FLOWLOGS_LOG_GROUP = os.environ["FLOWLOGS_LOG_GROUP"]
SNS_TOPIC = os.environ["SNS_TOPIC_ARN"]
BUCKET = os.environ["SENSITIVE_BUCKET"]
THRESHOLD = int(os.environ.get("THRESHOLD_READS", "100"))

# Expected readers per bucket
EXPECTED_READERS = {
    "customer-records-prod": [
        "arn:aws:iam::123456789012:role/AnalyticsPipeline",
        "arn:aws:iam::123456789012:role/ComplianceAudit",
    ],
}


def run_query(log_group, query, start, end):
    """Start a Logs Insights query and wait for it to finish."""
    started = logs.start_query(
        logGroupName=log_group,
        startTime=start,
        endTime=end,
        queryString=query,
    )
    query_id = started["queryId"]
    while True:
        outcome = logs.get_query_results(queryId=query_id)
        if outcome["status"] in ("Complete", "Failed", "Cancelled"):
            break
        time.sleep(1)
    if outcome["status"] != "Complete":
        raise RuntimeError(f"Query did not complete: {outcome['status']}")
    return [{f["field"]: f["value"] for f in row} for row in outcome["results"]]


def private_ip_for_principal(principal_id):
    """Resolve an EC2 instance role principalId to its private IP."""
    if ":" not in principal_id:
        return None
    instance_id = principal_id.split(":", 1)[1]
    if not instance_id.startswith("i-"):
        return None
    reservations = ec2.describe_instances(InstanceIds=[instance_id])
    for reservation in reservations["Reservations"]:
        for instance in reservation["Instances"]:
            return instance.get("PrivateIpAddress")
    return None


def egress_bytes(src_addr, start, end):
    """Sum external egress bytes for one source address."""
    query = f"""
    fields srcAddr, dstAddr, bytes
    | filter action = "ACCEPT" and srcAddr = "{src_addr}"
    | filter dstAddr not like /^10\\./
            and dstAddr not like /^192\\.168\\./
            and dstAddr not like /^172\\.(1[6-9]|2[0-9]|3[0-1])\\./
    | stats sum(bytes) as totalBytes
    """
    rows = run_query(FLOWLOGS_LOG_GROUP, query, start, end)
    if rows and rows[0].get("totalBytes"):
        return int(rows[0]["totalBytes"])
    return 0


def lambda_handler(event, context):
    try:
        # 1-hour lookback absorbs CloudTrail's 5-15 min delivery latency;
        # correlation happens on eventTime via 10-min bins in the query below.
        end = int(time.time())
        start = end - 3600  # 1 hour lookback
        allowed = EXPECTED_READERS.get(BUCKET, [])

        access_query = f"""
        fields userIdentity.arn, userIdentity.principalId
        | filter eventSource = "s3.amazonaws.com" and eventName = "GetObject"
        | filter requestParameters.bucketName = "{BUCKET}"
        | stats count(*) as objectReads
                by userIdentity.arn, userIdentity.principalId, bin(10m)
        | filter objectReads > {THRESHOLD}
        """

        for row in run_query(CLOUDTRAIL_LOG_GROUP, access_query, start, end):
            principal = row.get("userIdentity.arn")
            if not principal or principal in allowed:
                continue

            message = (
                f"Principal {principal} read {row.get('objectReads')} "
                f"objects from {BUCKET}."
            )

            ip = private_ip_for_principal(row.get("userIdentity.principalId", ""))
            if ip and egress_bytes(ip, start, end) > 1_000_000_000:
                message += (
                    f" The same source ({ip}) also sent a large volume of "
                    f"data to external destinations in the same window."
                )

            sns.publish(
                TopicArn=SNS_TOPIC,
                Subject="Unexpected S3 access detected",
                Message=message,
            )
    except ClientError as error:
        logger.error(f"AWS API error: {error}")
        raise
    except Exception as error:
        logger.error(f"Unexpected error: {error}")
        raise
    finally:
        logger.info("Correlation check completed")
  1. On the Configuration tab, choose General configuration, then choose Edit. Set Timeout to 5 minutes (300 seconds). CloudWatch Logs Insights queries run asynchronously and can take 30 to 60 seconds against large log groups. Choose Save.
  2. On the Configuration tab, choose Environment variables, then choose Edit, and add CLOUDTRAIL_LOG_GROUP, FLOWLOGS_LOG_GROUP, SNS_TOPIC_ARN, SENSITIVE_BUCKET, and THRESHOLD_READS.
  3. On the Configuration tab, choose Permissions, open the execution role, and attach the following least-privilege policy.
{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": ["logs:StartQuery", "logs:GetQueryResults"],
      "Resource": [
        "arn:aws:logs:REGION:ACCOUNT-ID:log-group:aws-cloudtrail-logs-my-trail:*",
        "arn:aws:logs:REGION:ACCOUNT-ID:log-group:vpc-flow-logs:*"
      ]
    },
    {
      "Effect": "Allow",
      "Action": "ec2:DescribeInstances",
      "Resource": "*"
    },
    {
      "Effect": "Allow",
      "Action": "sns:Publish",
      "Resource": "arn:aws:sns:REGION:ACCOUNT-ID:security-correlation-alerts"
    }
  ]
}

Replace REGION, ACCOUNT-ID, and the log-group names with your values. The ec2:DescribeInstances action doesn’t support resource-level permissions, so Resource: "*" is required for that statement; the other statements are scoped to specific ARNs.

To schedule automated runs

Amazon EventBridge (a serverless event bus that connects applications using events) runs targets on a schedule. Create one from the command line, using the role you made earlier.

aws scheduler create-schedule \
  --name s3-access-correlation-hourly \
  --schedule-expression "rate(1 hour)" \
  --target "Arn=arn:aws:lambda:REGION:ACCOUNT-ID:function:CorrelationFunction,RoleArn=arn:aws:iam::ACCOUNT-ID:role/EventBridgeSchedulerRole" \
  --flexible-time-window "Mode=OFF"

Step 6: Add enrichment context (optional)

Enrichment cuts triage time by adding an independent signal, but it isn’t required for the correlation to work. This step adds costs. You pay your geolocation provider for API calls, and the additional Lambda execution time increases your Lambda charges. To add IP geolocation, sign up for a geolocation API, add this function to the code, and call it where the handler resolves an IP.

import urllib.request
import json

def geo_context(ip_address):
    """Enrich an IP address with geolocation data from your provider."""
    try:
        url = f"https://your-geolocation-api.example/json/{ip_address}"
        with urllib.request.urlopen(url, timeout=5) as response:
            data = json.load(response)
        return {
            "country": data.get("country_name"),
            "city": data.get("city"),
            "org": data.get("org"),
        }
    except Exception as error:
        logger.warning(f"Geolocation lookup failed for {ip_address}: {error}")
        return None

Inside the handler’s loop, after you resolve ip, append the location to the alert.

            if ip:
                geo = geo_context(ip)
                if geo:
                    message += (
                        f" Source location: {geo['city']}, "
                        f"{geo['country']} ({geo['org']})."
                    )

Step 7: Scale to additional patterns and accounts

As your library grows, move the logic into automated pipelines with EventBridge, Lambda, and AWS Step Functions (a serverless orchestration service that coordinates multiple services into workflows), and surface correlations next to findings in Security Hub. For cross-service correlation at scale, CloudWatch unified data and telemetry capabilities can convert security and compliance data into the OCSF format and let you query sources such as CloudTrail, VPC Flow Logs, and DNS logs from one interface. Security Lake with Athena is a strong option for long-term analysis. Choose the endpoint that fits your retention and query needs.

Figure 3 shows a correlation pipeline built on AWS services including EventBridge, Lambda, Step Functions, and AWS Security Hub. The pipeline runs from data sources through scheduled queries and enrichment to automated response and centralized visibility.

Figure 3: A correlation pipeline built on AWS services

Figure 3: A correlation pipeline built on AWS services

Conclusion

You now have four correlation patterns that layer your business context on top of GuardDuty Extended Threat Detection to catch attacks specific to your environment. A few principles carry across every correlation you build.

  • Identity is your primary correlation key: Track the same principal across services.
  • Time windows matter, but they depend on the attack: Events minutes apart are usually related for fast, automated sequences; the ten-minute bins here work for that pattern. Slow or manual reconnaissance can stretch across hours or days, so widen the window when the pattern is deliberate rather than automated.
  • Context is what you add: Your data classification, access norms, resource ownership, and change windows are signals you bring to detection.
  • Start with one rule: A single well-tuned correlation catches more significant activity than a wall of uncorrelated alerts.

GuardDuty Extended Threat Detection handles the multi-stage patterns common across customers. The correlations in this post add the layer that only your business context can supply. Start with one pattern this week, validate it against your own traffic, and add the next pattern after the first proves reliable.

Have you built correlation rules for patterns not covered here? Share your experience in the Comments section below.

Further reading

 

Nisha Kashyap

Nisha Kashyap

Nisha Kashyap is a Senior Support Security Engineer at AWS. She works on threat detection and security operations, helping customers investigate security events and build detection that connects signals across AWS services and reflects their own environment.

How AWS IAM role manager rethinks the starting point for IAM roles

13 August 2026 at 00:16

When you build a new application or capability on Amazon Web Services (AWS), you want to focus on what you’re building. Getting a service running almost always begins with AWS Identity and Access Management (IAM). Many AWS services that act on your behalf need an IAM role, an identity the service assumes to access your resources with a defined set of permissions. You then author a trust policy so the service can assume the role, choose the permissions the workload needs, and attach it. Configuring roles and policies for common patterns is repeatable work that doesn’t need to be manual.

IAM role manager does that work for you. When role manager is enabled, AWS creates and configures the IAM roles as you build in supported service consoles, so you can start using a service and let AWS handle the role behind it. You create the resource you want, and role manager provisions and attaches the role you need as part of the same flow, so you can build now and refine permissions as your workload matures.

With that step automated, getting started takes minutes. You can create an AWS Lambda function and start running your code, with its execution role already created and attached, without switching context to set one up. Role creation becomes an automated part of building your application rather than a separate step.

Role manager is especially useful when you’re getting started: the moments when you want to stand up a service or get a proof of concept running and want to defer role configuration until later in your development process. You don’t need prior IAM experience to get started. You keep full control of what it creates, because the roles are ordinary IAM roles that you can view, edit, or delete like any role you author yourself. When you want to tighten a role, AWS IAM Access Analyzer reviews how it has been used and recommends a policy scoped to only the permissions it needs.

How to enable role manager

Role manager has two states, enabled and disabled. Enabling it for an account authorizes AWS to create roles in that account. In an organization, administrators can use a service control policy (SCP) to control whether member accounts can enable or use role manager. To enable it:

  1. Open the IAM console and choose Account settings.
  2. In the role manager section, choose Enable.

Figure 1: Enable Role Manager

Figure 1: Enable Role Manager

Some AWS services already create a role for you when you create a resource that needs one. Role manager doesn’t change that: those services keep creating roles automatically, and roles you already created keep working. What role manager adds is a single account-level control, and coverage for a case that built-in flows can’t handle: tasks whose permissions AWS can’t determine in advance, such as running your own code. For those tasks, role manager provisions a role that you can narrow later.

Example: Create an Amazon EventBridge rule

Start with a common task: an Amazon EventBridge rule that invokes a target, such as an Amazon Simple Queue Service (Amazon SQS) queue or an Amazon Simple Notification Service (Amazon SNS) topic. Without role manager, you would pause here to create a role that lets EventBridge invoke the target, write the role’s trust policy, attach the required permissions, and then return to finish the rule. With role manager enabled, you define the rule and its target, choose Create, and role manager provisions the role and attaches it for you. The EventBridge console shows the rule created and ready, and you never open the role-creation flow.

Figure 2: Creating an EventBridge rule with no manual role setup

Figure 2: Creating an EventBridge rule with no manual role setup

The role comes from an AWS managed role template: a definition AWS builds and maintains for a specific task, with the trust policy and permissions already worked out. The console calls a new IAM API, AcquireRole, which finds the matching template, provisions the role from it, and returns it to EventBridge. Depending on the service, AcquireRole either creates a new role or reuses one that already fits, so an account does not fill up with duplicate roles for the same task.

Role manager creates the role using your own IAM permissions, not a separate role-manager permission. To provision a new role, you need permission for the actions the template performs: at minimum, you need permissions to create and attach roles. When AcquireRole reuses an existing role instead of creating one, it needs only iam:GetRole and iam:GetRoleTemplateVersion. If you’re missing either of these permissions, the console tells you which one is needed rather than creating the role.

Run code that calls other AWS services

Not every task has a set of permissions AWS can define in advance. When a role runs your own code, such as a Lambda function, AWS has no way of knowing which services that code will call. Role manager covers this case too: create a Lambda function with role manager enabled, and it attaches an execution role that your code can use right away and that you can narrow once you know what the function calls.

Because the permissions your code needs aren’t known up front, role manager attaches the AWS managed policy PowerUserAccess to the role. PowerUserAccess grants access to AWS services so your function can call what it needs. By design, it doesn’t grant permission to manage IAM, AWS Organizations, or account settings. The template also configures the role to trust only the Lambda service.

Figure 3: Create an AWS Lambda function with no manual role setup

Figure 3: Create an AWS Lambda function with no manual role setup

Role manager attaches an execution role, and your function is ready to run. Figure 4 shows the Execution role panel on the function’s Configuration tab, with the role that role manager attached.

Figure 4: Role manager provides a role automatically to an AWS Lambda function

Figure 4: Role manager provides a role automatically to an AWS Lambda function

You can open the role in the IAM console to review its permissions. Figure 5 shows the role’s Permissions tab with the PowerUserAccess policy attached.

Figure 5: Permissions of the role provided by role manager for an AWS Lambda function

Figure 5: Permissions of the role provided by role manager for an AWS Lambda function

You keep full visibility into what role manager creates. Every role it creates records the role template it came from, and both GetRole and ListRoles return that template reference. You can inspect any role in your account and tell which were created by role manager. You read a role’s trust policy and permissions the same way you would for a role you authored, and AWS CloudTrail records each role’s creation.

Refining roles as workloads mature

As your workloads mature, refine the roles that role manager created to follow least privilege. When you’re ready, you can disable role manager and get IAM Access Analyzer unused access analysis at no additional cost for 90 days. Access Analyzer looks at how each role has been used and recommends a policy you can apply that keeps only the permissions the role needs. Start with the roles attached to your most critical workloads and work outward.

Disabling role manager doesn’t disrupt anything already running: your resources keep the roles they have, those roles stay in your account until you change them, and from that point you author new roles yourself, the same as before. If you would rather narrow a single role than the whole account, editing that role removes it from role manager’s control and it becomes a standard customer-managed role, with your changes preserved. In sandbox or development accounts, keeping role manager enabled saves time. For production workloads, disable role manager and refine the roles it created to least privilege before going live.

Conclusion

Role manager automates IAM role setup so you can focus on building from the start. When you enable it, AWS creates and attaches the IAM roles your resources need as you build, so you can start in minutes without prior IAM experience. Because these are IAM roles that you fully control, you keep the same visibility and the same tools you already use. Keep role manager enabled while you build, and refine the roles it created as your workloads mature.

To get started, enable role manager in the IAM console and create a resource in a supported service. To learn more, see IAM role creation and the list of supported services in the IAM User Guide.

If you have feedback about this post, submit comments in the Comments section below.


Zach Jiang

Zach Jiang

Zach is a Senior Technical Product Manager at AWS, specializing in AWS Identity products. He focuses on making identity the easy part of building on AWS for customers. Outside of technology, Zach enjoys traveling and exploring new cultures and cuisines.

David Sing

David Sing

David is a Principal Product Manager at AWS, specializing in AWS IAM. He focuses on simplifying IAM for builders and AI agents, safe credential issuance for AI agents, and authorization policy governing agent access. Outside of technology, David enjoys economics and markets, fishing, and time outdoors with his family.

Punit Deotale

Punit Deotale

Punit is a Software Development Manager on the AWS IAM team. He leads work on making it easier for customers to create and manage IAM roles directly within AWS service workflows, so they can set up the right permissions without leaving what they are doing. His focus is reducing permission-setup friction across AWS while helping customers stay aligned with least privilege. Outside of work, Punit enjoys reading, building side projects, and being outdoors.

Securing your Amazon S3 buckets: Identifying and remediating over-permissioned access

7 August 2026 at 18:46

Misconfigured Amazon Simple Storage Service (Amazon S3) buckets can expose your data to unauthorized access. Without proactive review, S3 bucket policies or Access Control Lists (ACLs) configured with broad access may go unnoticed in your environment. In this post, you learn how to identify and fix over-permissioned S3 buckets across your AWS environment, along with best practice recommendations and automation opportunities to help you prevent security gaps. This post provides a workflow framework and methodology recommendations for your security team to adapt. The focus of this post is on the what and why rather than a prescriptive implementation. You will need to customize the approach based on your organization’s requirements and existing security tooling.

This solution is intended for security engineers, cloud architects, and DevOps teams managing single- or multiple-account AWS environments with Amazon S3 workloads that require access management.

Prerequisites

Before you begin, make sure you have the following in place:

Solution overview

This solution uses a five-phase workflow diagram to detect, remediate, and continuously monitor over-permissioned S3 buckets across your AWS accounts. The following workflow diagram illustrates the high-level end-to-end process for identifying and remediating over-permissioned S3 buckets across your Amazon Web Services (AWS) environment.

Figure 1: Amazon S3 over-permissive access – Detection, remediation, monitoring and cleanup workflow

Figure 1: Amazon S3 over-permissive access – Detection, remediation, monitoring and cleanup workflow

The diagram in Figure 1 consists of five phases:

  1. Setup and prerequisites – Configure AWS Organizations or multi-account access, designate a central security account, deploy AWS Config across all accounts, and enable AWS Security Hub with a central administrator.
  2. Detection and identification – Deploy AWS Config rules (such as s3-bucket-public-read-prohibited and s3-bucket-public-write-prohibited) and run an audit Lambda function that scans each S3 bucket. The function checks three areas: Public Access Block configuration, bucket policy status, and bucket ACL grants. Buckets with issues are added to a risky buckets list. The function then generates a report in CSV and JSON format, uploads it to an output S3 bucket, and sends an SNS alert.
  3. Remediation – Address findings using one or more approaches – Apply restrictive bucket policies to deny public read/write access and restrict access to specific IAM principals; deploy a remediation Lambda function to automatically update bucket policies and disable public access settings; or use CloudFormation StackSets to deploy standardized policies across multiple accounts.
  4. Continuous monitoring – Schedule the audit Lambda function for recurring scans (daily or weekly) using Amazon EventBridge. Use EventBridge to detect policy changes, configure automated notifications for new violations, enable IAM Access Analyzer for S3 to identify external access, and run regular compliance scans.
  5. Resource cleanup – Review and delete resources created during the audit that are no longer needed, including Lambda functions and IAM roles, EventBridge rules, SNS topics and subscriptions, audit output S3 buckets, AWS Config rules, and Security Hub (if enabled only for this audit).

Cost considerations

This section covers the AWS services used in this solution and their associated costs so you can estimate spend before deployment. The primary cost drivers are AWS Config and Security Hub, which scale with the number of accounts and resources you monitor. Lambda, Amazon EventBridge, Amazon SNS, and Amazon S3 typically add minimal costs for most environments. Start with a pilot in one or two accounts to validate costs before scaling.

  • AWS Config – Charges per configuration item recorded and per rule evaluation. Costs scale with the number of accounts and resources tracked.
  • Security Hub – Charges per account per AWS Region for security checks and finding ingestion.
  • Lambda – Charges per request and per GB-second of compute time.
  • EventBridge – Scheduled rules are free. Custom event bus usage might incur charges.
  • Amazon SNS – Charges per notification delivered.
  • Amazon S3 – Storage costs for audit report output files. Minimal for most environments.
  • AWS IAM Access Analyzer – Check the AWS IAM Access Analyzer pricing page to understand which features have costs associated with them.

Check the service pricing pages for current rates. Use the AWS Pricing Calculator to estimate costs for your specific environment before enabling services across all accounts. Consider starting with a pilot in one or two accounts to validate costs before scaling.

Detect and report over-permissioned buckets

This section walks you through setting up the audit environment, deploying the Lambda-based scanner, and generating reports of over-permissioned S3 buckets across your accounts. Follow these steps to identify over-permissioned S3 buckets in your multi-account environment, starting with preparing your environment for an Amazon S3 audit.

To set up the multi-account audit environment:

  1. Set up AWS Organizations or multi-account access. Set up centralized management of your AWS accounts using AWS Organizations or configure cross-account IAM roles.
  2. Choose a central security account. Choose one account as your security/audit account. This account will run the audit Lambda function and collect results from member accounts.
  3. Create an Amazon SNS topic for alerts. Subscribe your security team to receive notifications when over-permissioned buckets are detected. Note the topic Amazon Resource Name (ARN) from the output—you will need it when creating the Lambda execution role (step 6) and the Lambda function (step 9). Confirm the email subscription before testing; Amazon SNS doesn’t deliver alerts until the subscription is confirmed. Learn more in the Amazon SNS Developer Guide.
  4. (Optional): Create an S3 bucket for audit reports. If you plan to use Script v2 for historical reporting and trend analysis, create a dedicated bucket now. Skip this step if you only need real-time alerts using Script v1.
  5. Plan cross-account IAM roles. The central security account needs permission to scan member accounts. Design cross-account roles that:
    1. Grant minimum Amazon S3 read permissions (list buckets, read policies, ACLs, public access configurations).
    2. Include an external ID condition to mitigate the confused deputy problem.
    3. Can be deployed consistently using AWS CloudFormation StackSets.
    4. See the IAM documentation on creating cross-account roles, The confused deputy problem, and IAM security best practices for additional guidance on role configuration and trust policies.

      Note: The specific trust policy and permissions policy for your cross-account roles will depend on organizational requirements. Work with your IAM administrators to grant minimum necessary access for the audit function.

  6. Create the Lambda execution role. Create an IAM role for your Lambda function with the permissions it needs to scan buckets, publish alerts, and write logs. Apply the principle of least privilege—grant only the minimum Amazon S3 read permissions required for the audit (such as, listing buckets, reading bucket policies, ACLs, and public access block configurations), Amazon SNS publish permission for the alert topic created in step 3, Amazon S3 write permission for the output bucket created in step 4 (Script v2), and Amazon CloudWatch Logs permissions. For multi-account scanning, also include sts:AssumeRolepermission for the cross-account role ARNs created in step 5. The AWS Lambda execution role documentation has instructions on creating and configuring execution roles.
  7. To deploy the S3 audit solution Deploy the audit components
    1. Enable AWS Config in member accounts. AWS Config provides compliance monitoring and can detect when S3 buckets are created or modified with public access settings. This will enable the Lambda-based audit to receive real-time detection between scheduled scans. The AWS Config Developer Guide has setup instructions. Deploy pre-defined AWS Config rules to identify overly permissive settings. These managed rules provide automated compliance checking. When AWS Config detects violations, it sends findings to Security Hub (configured in step 8) for centralized visibility alongside the Lambda audit results.
      • s3-bucket-public-read-prohibited
      • s3-bucket-public-write-prohibited
      • Create AWS Config rules for specific permission patterns. For the full list of available rules, see the AWS Config managed rules reference
  8. Enable Security Hub for centralized visibility. Enable AWS Security Hub in member accounts and configure the central security account as the administrator. Security Hub aggregates findings from AWS Config rules (step 7), IAM Access Analyzer (enabled later), and can receive custom findings from your Lambda audit function, providing a single dashboard for Amazon S3 security issues across your organization. See the Security Hub User Guide for setup details.
  9. Deploy the audit Lambda function. Deploy a Python Lambda function using the Boto3 library to list S3 buckets, check their policies, ACLs, and IAM permissions, and identify over-permissioned buckets. See the example scripts that follow.

Important: These code examples aren’t production ready. Adapt them to meet your organization’s requirements and test them in a non-production environment before deployment.

Choose your approach:

  • Script v1 – Best for immediate SNS alerts when issues are detected.
  • Script v2 – Best for historical reports, trend analysis using BI tools.
  • Both scripts – Best for different schedules and ongoing needs.

Audit Lambda function – Example script v1 (Scan and alert)

The following is an example of a Lambda function script for reference purposes. Review, adapt, and test before use in your environment, it scans all S3 buckets in the current account and checks for:

  • Public Access block configuration gaps
  • Bucket policies that allow public access
  • ACL grants to AllUsers

Note: Replace placeholder values with actual values before deployment:

  • <REGION>– Your AWS Region (for example, us-east-1)
  • <ACCOUNT_ID>– Your 12-digit AWS account ID
  • <TOPIC_NAME>– The name of your SNS topic created in step 3
import boto3
import json

def lambda_handler(event, context):
    s3 = boto3.client('s3')
    sns = boto3.client('sns')
    risky_buckets = []
    errors = []

    try:
        buckets = s3.list_buckets()['Buckets']
    except Exception as e:
        return {'statusCode': 500, 'body': f'Failed to list buckets: {str(e)}'}

    for bucket in buckets:
        bucket_name = bucket['Name']
        issues = []

        try:
            # Check Public Access Block — all four settings should be enabled
            try:
                pab = s3.get_public_access_block(Bucket=bucket_name)
                config = pab['PublicAccessBlockConfiguration']
                if not all([
                    config.get('BlockPublicAcls'),      # Block new public ACLs
                    config.get('BlockPublicPolicy'),     # Block new public bucket policies
                    config.get('IgnorePublicAcls'),      # Ignore existing public ACLs
                    config.get('RestrictPublicBuckets')   # Restrict access to public buckets
                ]):
                    issues.append('Public Access Block not fully enabled')
            except s3.exceptions.NoSuchPublicAccessBlockConfiguration:
                issues.append('No Public Access Block configured')

            # Check bucket policy — flag if policy status is public
            try:
                policy_status = s3.get_bucket_policy_status(Bucket=bucket_name)
                if policy_status['PolicyStatus']['IsPublic']:
                    issues.append('Bucket policy allows public access')
            except s3.exceptions.NoSuchBucketPolicy:
                pass  # No bucket policy is acceptable

            # Check bucket ACL
            acl = s3.get_bucket_acl(Bucket=bucket_name)
            for grant in acl.get('Grants', []):
                grantee = grant.get('Grantee', {})
                uri = grantee.get('URI', '')
                # 'AllUsers' = anonymous public access
                # 'AuthenticatedUsers' = any AWS account (still overly permissive)
                if grantee.get('Type') == 'Group' and ('AllUsers' in uri or 'AuthenticatedUsers' in uri):
                    issues.append('Bucket ACL grants public access')
                    break

            if issues:
                risky_buckets.append({'bucket': bucket_name, 'issues': issues})

        except Exception as e:
            errors.append(f'{bucket_name}: {str(e)}')

    # Send alert if risky buckets found
    if risky_buckets:
        message = f'Found {len(risky_buckets)} buckets with public access:\n\n'
        for item in risky_buckets:
            message += f"  {item['bucket']}: {', '.join(item['issues'])}\n"

        sns.publish(
            TopicArn='arn:aws:sns:<REGION>:<ACCOUNT_ID>:<TOPIC_NAME>',
            Subject='S3 Public Access Alert',
            Message=message
        )

    return {
        'statusCode': 200,
        'body': json.dumps({
            'risky_buckets': risky_buckets,
            'errors': errors,
            'total_checked': len(buckets)
        })
    }

Multi-account scanning: This script scans the current account only. To scan across member accounts, see the Multi-account extension section later in this post.

Audit Lambda function – Example script v2 (CSV and JSON report)

The following is an example Lambda function script for reference purposes. Before deploying any script, review error handling, logging, output structure, and permissions. This script generates CSV and JSON output files and uploads them to an S3 bucket for reporting and business intelligence (BI) dashboard integration.

You can deploy both functions with different EventBridge schedules, for example, Script v1 daily for alerts and Script v2 weekly for reports.

Note: Before you deploy this script, replace <OUTPUT_BUCKET_NAME> with the S3 bucket you created for audit reports in step 4.

import boto3
import csv
import json
import os

def lambda_handler(event, context):
    s3 = boto3.client('s3')
    buckets = s3.list_buckets()['Buckets']

    full_access_buckets = []
    for bucket in buckets:
        bucket_name = bucket['Name']
        try:
            bucket_policy = s3.get_bucket_policy(Bucket=bucket_name)['Policy']
            policy = json.loads(bucket_policy)
            for statement in policy['Statement']:
                if (statement['Effect'] == 'Allow'
                    and statement['Principal'] == '*'
                    and 'Action' in statement
                    and 's3:*' in statement['Action']):
                    full_access_buckets.append({'BucketName': bucket_name})
                    break
        except s3.exceptions.ClientError as e:
            if e.response['Error']['Code'] != 'NoSuchBucketPolicy':
                print(f'Error checking bucket policy for {bucket_name}: {e}')

    # Output CSV
    csv_output = os.path.join('/tmp', 'full_access_buckets.csv')
    with open(csv_output, 'w', newline='') as csvfile:
        writer = csv.DictWriter(csvfile, fieldnames=['BucketName'])
        writer.writeheader()
        writer.writerows(full_access_buckets)

    # Output JSON
    json_output = os.path.join('/tmp', 'full_access_buckets.json')
    with open(json_output, 'w') as jsonfile:
        json.dump(full_access_buckets, jsonfile, indent=2)

    # Upload to Amazon S3
    output_bucket = '<OUTPUT_BUCKET_NAME>'
    s3.upload_file(csv_output, output_bucket, 'full_access_buckets.csv')
    s3.upload_file(json_output, output_bucket, 'full_access_buckets.json')

    return {
        'statusCode': 200,
        'body': json.dumps(f'CSV and JSON files uploaded to {output_bucket}')
    }

Important: If this function runs on a schedule, consider implementing a file naming strategy with timestamps to prevent overwriting previous reports or establish a lifecycle policy to manage retention. Include the output bucket in your cleanup procedures when the auditing process is no longer needed.

What if no over-permissioned buckets are found?

If the audit scan returns zero risky buckets, document the clean baseline for future comparison and move to the verification and monitoring phase to so new buckets or policy changes don’t introduce risk over time.

Multi-account extension

The preceding example scripts scan buckets in the current account only. To scan across member accounts in your organization, add the following AssumeRole logic. This function assumes the cross-account IAM role you created during setup, then returns an Amazon S3 client with temporary credentials for each member account.

Note: Before you deploy, configure the following Lambda environment variables:

  • <MEMBER_ACCOUNTS> – Comma-separated list of 12-digit account IDs to scan (for example, 111111111111,222222222222)
  • <CROSS_ACCOUNT_ROLE_NAME> – The IAM role name created in each member account (for example, S3AuditRole)
  • <EXTERNAL_ID> – The external ID configured in the trust policy (for example, s3-audit-external-id)
import boto3
import os

def get_member_s3_clients():
    """
    Assumes the cross-account audit role in each member account
    and returns a list of (account_id, s3_client) tuples.
    """
    sts = boto3.client('sts')
    member_accounts = os.environ.get('<MEMBER_ACCOUNTS>', '').split(',')
    cross_account_role_name = os.environ.get('<CROSS_ACCOUNT_ROLE_NAME>')
    external_id = os.environ.get('<EXTERNAL_ID>')

    clients = []
    for account_id in member_accounts:
        account_id = account_id.strip()
        if not account_id:
            continue

        try:
            assumed_role = sts.assume_role(
                RoleArn=f'arn:aws:iam::{account_id}:role/{cross_account_role_name}',
                RoleSessionName='S3AuditSession',
                ExternalId=external_id
            )

            # Create S3 client with assumed credentials
            s3_client = boto3.client(
                's3',
                aws_access_key_id=assumed_role['Credentials']['AccessKeyId'],
                aws_secret_access_key=assumed_role['Credentials']['SecretAccessKey'],
                aws_session_token=assumed_role['Credentials']['SessionToken']
            )
            clients.append((account_id, s3_client))

        except Exception as e:
            print(f'Failed to assume role in account {account_id}: {e}')

    return clients

To scan each member account, replace the single-account s3.list_buckets() call with a loop over member accounts:

def lambda_handler(event, context):
    all_risky_buckets = []
    all_errors = []

    # Scan each member account
    for account_id, s3_client in get_member_s3_clients():
        try:
            buckets = s3_client.list_buckets()['Buckets']
            for bucket in buckets:
                # ... same scanning logic as the single-account scripts ...
                # Use s3_client instead of s3 for each API call
                pass
        except Exception as e:
            all_errors.append(f'Account {account_id}: {e}')

    # ... same alerting/reporting logic ...

The Lambda execution role in the central security account needs sts:AssumeRole permission for the cross-account role ARNs. Add this to the execution role policy you created in step 5.

Remediate elevated access

This section describes how to fix over-permissioned buckets using account-level controls, bucket policies, and optional automation. Any elevated access that you find needs to be remediated.

Enable Amazon S3 Block Public Access (account level)

Before applying individual bucket policies, enable Amazon S3 Block Public Access at the account level. This prevents buckets in the account from being made public, regardless of individual bucket policies or ACLs. See theS3 Block Public Access documentation for configuration details. See the following example AWS CLI command; replace <ACCOUNT_ID> with the ID of the account you’re using to manage resource access:

aws s3control put-public-access-block \
  --account-id <ACCOUNT_ID> \
  --public-access-block-configuration \
BlockPublicAcls=true,IgnorePublicAcls=true,BlockPublicPolicy=true,RestrictPublicBuckets=true

For multi-account environments, deploy this setting across member accounts using AWS CloudFormation StackSets or AWS Organizations service control policies (SCPs).

Important: Before enabling account-level S3 Block Public Access, check whether any workloads need public bucket access (for example, static website hosting, public dataset sharing). Coordinate with your application teams to identify any exceptions.

Remediate using bucket policies

Implement bucket policies that restrict access to specific IAM users, roles, or accounts. When crafting policies, apply the principle of least privilege and include only the actions and principals required for your use case.

Example S3 bucket policy: deny public read/write access. Modify the resource ARN, actions, and conditions to match your requirements:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Deny",
      "Principal": "*",
      "Action": [
        "s3:PutObject", "s3:PutObjectAcl",
        "s3:GetObject", "s3:GetObjectAcl",
        "s3:DeleteObject"
      ],
      "Resource": "arn:aws:s3:::<BUCKET_NAME>/*",
      "Condition": {
        "StringEquals": {
          "s3:x-amz-acl": ["public-read", "public-read-write"]
        }
      }
    }
  ]
}

Example S3 bucket policy: restrict access to specific IAM principals. Replace <ACCOUNT_ID>, <USERNAME>, and <ROLE_NAME>:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "AllowObjectAccess",
      "Effect": "Allow",
      "Principal": {
        "AWS": [
          "arn:aws:iam::<ACCOUNT_ID>:user/<USERNAME>",
          "arn:aws:iam::<ACCOUNT_ID>:role/<ROLE_NAME>"
        ]
      },
      "Action": ["s3:GetObject", "s3:PutObject", "s3:DeleteObject"],
      "Resource": "arn:aws:s3:::<BUCKET_NAME>/*"
    },
    {
      "Sid": "AllowBucketAccess",
      "Effect": "Allow",
      "Principal": {
        "AWS": [
          "arn:aws:iam::<ACCOUNT_ID>:user/<USERNAME>",
          "arn:aws:iam::<ACCOUNT_ID>:role/<ROLE_NAME>"
        ]
      },
      "Action": ["s3:ListBucket", "s3:GetBucketLocation"],
      "Resource": "arn:aws:s3:::<BUCKET_NAME>"
    }
  ]
}

See the Amazon S3 bucket policy documentation for additional examples and guidance.

Automate remediation with Lambda or CloudFormation StackSets (optional):

You can also remediate using Lambda or CloudFormation Stacksets:

  • Create Lambda functions to automatically update bucket policies or disable public access settings for flagged buckets
  • Use CloudFormation StackSets to deploy standardized bucket policies and S3 Block Public Access settings across multiple accounts

Verify your remediation

This section explains how to confirm that your fixes are effective before moving to ongoing monitoring. After applying remediation, verify the fix is effective before setting up ongoing monitoring:

  1. Re-run the audit Lambda function – Confirm the previously flagged buckets no longer appear in the risky buckets list.
  2. Check Security Hub compliance – Verify the compliance status has changed from FAILED to PASSED for Amazon S3-related controls.
  3. Validate with IAM Access Analyzer – Review findings for the remediated S3 buckets. Active findings should resolve automatically after public access is removed.
  4. Test application functionality – Confirm that legitimate workloads continue to function correctly.

Document the verification results for your auditing needs. If any S3 buckets still show issues, investigate whether the policy was applied correctly or if there are conflicting permissions.

Automation opportunities

This section covers optional strategies to automate ongoing detection and maintain your security posture without manual intervention.

  1. (Optional) Schedule recurring scans with Amazon EventBridge
    • Regular security scans help identify new issues arising from configuration changes or newly created S3 buckets. When new security risks are detected, Amazon SNS sends an alert and automatically initiates the remediation phase (Workflow 2 in Figure 1). To avoid repeated alerts, you can configure the audit Lambda function to run on a schedule and compare current results with the previous baseline to generate notifications when new findings are discovered.
    • For ongoing monitoring, you can schedule the audit Lambda function to run on a recurring basis using EventBridge. Create a scheduled rule with a cron expression (for example, daily at 6:00 AM UTC or weekly on Mondays), add the Lambda function as the target, and grant EventBridge permission to invoke it. See Amazon EventBridge scheduling documentation for instructions on creating scheduled rules and configuring targets.
  2. Enable IAM Access Analyzer for Amazon S3
    • IAM Access Analyzer monitors bucket policies, ACLs, and access points to identify buckets accessible from outside your account or organization. Create an analyzer scoped to your organization or individual account, then review findings to identify unintended external access. Findings automatically flow into Security Hub when both services are enabled, giving you a dashboard view for Amazon S3 security findings. See the IAM Access Analyzer documentation for setup and usage instructions.
  3. Automate notifications for policy drift
    • Recurring scans might surface new findings from policy drift or newly created buckets. When new risks are detected, Amazon SNS alert triggers and the remediation cycle repeat (as shown in Workflow 2 in Figure 1) sends email notifications. Configure the audit Lambda function to compare current scan results against the previous baseline and alert on new findings for ongoing reviews.

Clean up

This section lists the resources created during this walkthrough that you should review and remove when they are no longer needed. If the following services were not previously active in your account, leaving them enabled might result in additional ongoing charges. See the Cost considerations section for details. Review and remove unused resources to optimize costs.

Delete or disable the following script-generated resources if they’re not required after outputs are generated. Focus first on Lambda functions and EventBridge rules if you’re not running recurring scans. If you enabled AWS Config or Security Hub specifically for this audit, evaluate whether you need them for other compliance requirements before disabling.

  • Lambda – Functions, IAM roles, and policies created for auditing
  • Amazon EventBridge – Scheduled rules created for recurring audit triggers
  • Amazon SNS – Topics and subscriptions created for notifications
  • Amazon S3 – Buckets containing script-generated audit output files
  • AWS Config – Rules and recorders if no longer needed for compliance
  • Security Hub – Disable if enabled solely for this audit
  • IAM Access Analyzer – Delete the analyzer if no longer needed for ongoing monitoring

Note: Be careful when deleting data and consider temporarily disabling services first to check for dependencies. Only delete resources generated as part of your audit outputs. Verify you have retained any necessary results before proceeding. Verify resources are not used by other workloads before deletion.

Best practices

This section provides recommendations to maintain secure Amazon S3 configurations long-term. To learn more about maintaining secure Amazon S3 configurations, review the AWS documentation links provided in the conclusion. The following recommendations aren’t exhaustive. Adapt and extend them based on your organization’s evolving security requirements and AWS best practices guidance. After you’ve fixed existing issues, these practices help you maintain secure Amazon S3 configurations.

  • Start with account-level controls – Enable S3 Block Public Access at the account level. This prevents buckets from becoming public even if someone misconfigures an individual bucket policy. For multi-account environments, enforce this through AWS Organizations SCPs.
  • Automate detection – Use IAM Access Analyzer to detect external access. Schedule your audit Lambda function with EventBridge to catch new issues weekly or daily, depending on your change frequency. Compare scan results against previous baselines to identify drift.
  • Standardize across accounts – Use CloudFormation StackSets to deploy the same secure configuration to all accounts in your organization, reducing the chance of configuration drift. Use StackSets for IAM roles, AWS Config rules, and S3 Block Public Access settings.

Additional security measures

  • Regularly review and rotate cross-account IAM role credentials and external IDs
  • Implement Amazon S3 server-side encryption (SSE-S3 or SSE-KMS) for data at rest
  • Enable S3 access logging and AWS CloudTrail data events for audit trails

Conclusion

This section summarizes what you accomplished and suggests next steps to maintain your S3 security posture. By implementing the detection, remediation, and monitoring workflow outlined in this post, you can proactively identify and secure over-permissioned S3 buckets across your AWS environment. To maintain your ongoing security posture, enable IAM Access Analyzer for continuous monitoring and schedule recurring audits with EventBridge. To learn more about Amazon S3 security best practices, see Security best practices for Amazon S3

For more information:

If you have feedback about this post, submit comments in the Comments section below.


Hetal Kolekar

Hetal Kolekar

Hetal is a Sr. Technical Account Manager at AWS with more than 21 years of experience in Infrastructure Architecture, Security, Systems Engineering, and Consulting. He excels in leading teams to strengthen their cloud security posture and helps customers scale up their security using AWS services. Hetal is a guitarist and loves playing at church.

Manomayi Vedam

Manonmayi Vedam

Manonmayi is a Senior TAM and Product Owner at AWS, specializing in AI-driven cloud enablement, security, and generative AI risk across Healthcare, Financial Services, Energy, and Public Sector. She co-leads global security programs for Fortune 500 clients, contributes to the NIST Cyber AI Profile RMF and NCCoE, and is a Fellow at SCRS with recognition from GlobeeAwards and IEEE.

Fernando Freitas

Fernando Freitas

Fernando is a Sr. Technical Account Manager at AWS in Salt Lake City, focused on helping customers achieve their desired outcomes with the AWS Cloud. Fernando is passionate about Identity and Security, Training and Education.

Automate certificates with ACME support in AWS Certificate Manager

7 August 2026 at 00:03

Customers tell us that managing TLS certificates at scale is one of their biggest operational concerns. The Certification Authority Browser Forum (CA/Browser Forum) has mandated a phased reduction in maximum certificate validity for public certificates. By March 2027, the maximum validity drops to 100 days. By March 2029, it lasts for 47 days. For an organization managing 1,000 certificates, the final transition means roughly 30 renewal events every day. Renewal and rotations of renewed certificates at that cadence isn’t something manual processes or ticket-driven workflows can sustain at scale.

We recently announced Automated Certificate Management Environment (ACME) protocol support in AWS Certificate Manager (ACM). With this launch, you can use the ACME clients your teams already know, including popular open source tools like certbot, cert-manager, acme.sh, and win-acme, to automate public certificate issuance and renewal for your infrastructure. Customers that are using third-party certificate authorities (CAs) can point their existing ACME-compatible clients at ACM instead of their current CA, with minimal reconfiguration. This applies whether it’s running on Amazon Web Services (AWS), on premises, or in a hybrid environment. Certificates created through ACME are registered in ACM, giving you a unified view of your entire certificate inventory.

This post covers how the feature works, how to get started, and the controls and best practices to help you manage certificate issuance at scale.

Background

ACME is an open source protocol that automates the process of verifying domain ownership and issuing certificates and has become a standard mechanism for certificate automation. While ACM has long provided managed certificate issuance and renewal for AWS-integrated services such as Elastic Load Balancing (ELB), Amazon CloudFront, and Amazon API Gateway, many customers also need to automate certificates for their own infrastructure, including servers they manage in their data centers, Kubernetes clusters, Internet of Things (IoT) fleets, and hybrid environments. Until now, those customers had to turn to external providers. This launch brings the ACM automation model to that same infrastructure, using the standard ACME protocol with AWS managed certificate endpoints.

How it works

The feature introduces a new centrally provisioned and managed resource type: the ACME endpoint. Each endpoint is an AWS resource with a unique ACME directory URL and AWS Identity and Access Management (IAM)-based access controls. You create and manage endpoints through the ACM API or AWS Management Console, and point your existing ACME clients at the endpoint URL. Certificates issued through your endpoint are automatically registered with ACM, appearing in your certificate inventory alongside certificates created by the RequestCertificate and ImportCertificate API calls.

The architecture separates into two planes. In the control plane, PKI administrators use ACM APIs to create ACME endpoints, pre-approve the domains an endpoint is allowed to issue for, and generate external account binding (EAB) credentials. In the data plane, ACME clients register with an endpoint using EAB credentials and request certificates for domains the administrator has already validated. This architecture is how we provide customers the ability to scale. Instead of each client proving domain ownership on every request, a principal with appropriate ACM permissions (typically your PKI administrator) validates domains once at the endpoint level, and then application owners don’t need DNS credentials to get a certificate.

Adding to the data plane, EABs control client access to the endpoints. Each EAB is bound to an IAM role that controls what certificate operations the ACME client can perform, and credentials you generate in ACM are distributed to authorized ACME clients. An ACME client authorized for one endpoint can’t use a different endpoint. This creates security boundaries between environments. For example, a client authorized for your development endpoint can’t obtain certificates from your production endpoint.

Figure 1 shows the ACME request flow through ACM. An ACME client authenticates to an ACME endpoint using EAB credentials. The endpoint routes certificate orders to Amazon Trust Services for issuance. Issued certificates are registered in ACM inventory, where Amazon EventBridge and AWS CloudTrail provide expiration alerting and audit logging.

Figure 1: An ACME architecture and workflow

Figure 1: An ACME architecture and workflow

Getting started

Getting started with the new ACME feature in ACM is straightforward. Use the following steps to create your first ACME-generated certificate.

Prerequisites

  • An AWS account with permissions to create and manage ACM resources
  • An ACME client installed on your infrastructure (for example, Certbot, cert-manager, acme.sh, or others)
  • AWS Command Line Interface (AWS CLI) installed on your device (see this blog post for the console equivalent)
  • Amazon Route 53 hosted zone for your domain, or the ability to create a CNAME record with your DNS provider

Step 1: Create an ACME endpoint

Before you can use ACME clients with ACM, you need to create an ACME endpoint. This endpoint provides the URL that your ACME clients will use to request certificates.

  1. Run the following command from the AWS CLI to create an ACME endpoint:
    aws acm create-acme-endpoint \
      --authorization-behavior PRE_APPROVED \
      --certificate-authority '{"PublicCertificateAuthority":{"AllowedKeyAlgorithms":["EC_prime256v1"]}}
  2. Note the endpoint Amazon Resource Name (ARN) from the response.
    {"AcmeEndpointArn": "arn:aws:acm:us-east-1:123456789012:acme-endpoint/11111111-2222-3333-4444-555555555555"}
  3. Run the following command to retrieve the endpoint URL, replacing the ARN with your endpoint ARN:
    aws acm describe-acme-endpoint \
    --acme-endpoint-arn arn:aws:acm:us-east-1:123456789012:acme-endpoint/11111111-2222-3333-4444-555555555555
  4. Save the output of the ACME EndpointUrl:
    {
        "AcmeEndpoint": {
            "AcmeEndpointArn": "arn:aws:acm:us-east-1:123456789012:acme-endpoint/11111111-2222-3333-4444-555555555555",
            "EndpointUrl": "https://acm-acme-enroll.<region>.api.aws/6666666-7777-8888-9999-000000000000/directory",
            "Status": "ACTIVE",
            "AuthorizationBehavior": "PRE_APPROVED",
            "Contact": "REQUIRED",
            "CertificateAuthority": {
                "PublicCertificateAuthority": {
                    "AllowedKeyAlgorithms": [
                        "EC_prime256v1"
                    ]
                }
            },
            "CreatedAt": "2026-07-14T18:23:58.876000-04:00",
            "UpdatedAt": "2026-07-14T18:23:58.876000-04:00"
        }
    }
    

Step 2: Pre-approve a domain

Before ACME clients can request a certificate, the administrator validates the domain using DNS once at the endpoint level. Use DomainScope to control exactly which certificate patterns are allowed:

  • Enabling only ExactDomain restricts clients to that specific name,
  • Subdomains enabled allows names like api.example.com,
  • Wildcards enabled allows *.example.com.

Leave a scope disabled to block that pattern outright, even if an otherwise-valid ACME request asks for it. For a production endpoint, consider enabling only ExactDomain and Subdomains and leaving Wildcards disabled for a stricter posture.

aws acm create-acme-domain-validation \
--acme-endpoint-arn arn:aws:acm:us-east-1:123456789012:acme-endpoint/11111111-2222-3333-4444-555555555555 \
--domain-name example.com \
--prevalidation-options '{"DnsPrevalidation":{"DomainScope":{"ExactDomain":"ENABLED","Subdomains":"ENABLED","Wildcards":"DISABLED"},"HostedZoneId":"Z1234567890ABC"}}'

If your domain is hosted in Route 53, specifying HostedZoneId lets ACM create the required CNAME record automatically. If your domain is hosted elsewhere, omit it and create the provided CNAME record manually with your DNS provider. Validation typically completes within a few seconds after the record is in place.

You will receive the following response back:

{
    "AcmeDomainValidationArn": "arn:aws:acm:us-east-1:123456789012:acme-endpoint/1111111-2222-3333-4444-555555555555/acme-domain-validation/6666666-8888-9999-0000-11111111111"
}

Step 3: Generate EAB credentials

EAB credentials authenticate your ACME clients to your endpoint. Generate a unique set of credentials for each client or environment to maintain security boundaries.

  1. Run the following command to generate your EAB credentials, adjusting your expiration to fit your organization’s risk profile:
    aws acm create-acme-external-account-binding \
        --acme-endpoint-arn arn:aws:acm:region:111122223333:acme-endpoint/00000000-0000-0000-0000-000000000000 \
        --role-arn arn:aws:iam::111122223333:role/AcmeIssuanceRole \
        --expiration '{"Value": 7, "Type": "DAYS"}'
  2. Note the response from a successful invocation of the command
    {
        "ExternalAccountBinding": {
            "AcmeExternalAccountBindingArn": "arn:aws:acm:region:111122223333:acme-endpoint/00000000-0000-0000-0000-000000000000/acme-external-account-binding/1234567-1234-1234-1234-123456789012",
            "AcmeEndpointArn": "arn:aws:acm:region:111122223333:acme-endpoint/00000000-0000-0000-0000-000000000000",
            "RoleArn": "arn:aws:iam::123456789012:role/service-role/AcmAcmeIssuanceRole-XXXXXXXX",
            "ExpiresAt": "2026-07-21T18:47:50.641000-04:00"
        }
    }
    
  3. Run the following command to retrieve the credentials. You’ll need these values for your ACME client configuration the next step.
    aws acm get-acme-external-account-binding-credentials \
        --acme-external-account-binding-arn arn:aws:acm:region:111122223333:acme-endpoint/00000000-0000-0000-0000-000000000000/acme-external-account-binding/22222222-2222-2222-2222-222222222222
  4. Save the KeyId and MacKey for the next step.
    {
        "KeyId": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
        "MacKey": "xxxxxxxx-xxxxxxxxxx-xxxxxxxxxxxxxxx"
    }

Step 4: Configure your ACME client

With your endpoint URL and EAB credentials ready, you can now configure your preferred ACME client. The following examples show configuration for two popular clients. As a reminder, the server information was retrieved in step 1, part 4 as the EndpointUrl.

acme.sh:

acme.sh --issue --server https://acm-acme-enroll.us-east-1.api.aws/123457-1234-1234-123456789012/directory \
    --eab-kid <KeyId> --eab-hmac-key <MacKey> \
    --email <EMAIL> \
    -d <DOMAIN> \
    --dns --yes-I-know-dns-manual-mode-enough-go-ahead-please

Certbot:

certbot certonly --standalone --non-interactive --agree-tos \
  --email <EMAIL> \
  --server https://acm-acme-enroll.us-east-1.api.aws/1234567-1234-1234-123456789012/directory \
  --eab-kid <KeyId> \
  --eab-hmac-key <MacKey> \
  -d <DOMAIN>

After the initial registration, your ACME client handles renewals.

Enterprise controls

Other ACME alternatives can provide certificates but don’t give the same amount of control and governance for customers that need to scale their certificate environment. The following controls are available to help reduce risk across your organization.

Domain validation

Customers managing large numbers of domains told us they need a way to prevent unauthorized certificate issuance across their domain space. Domain validation gives you this control. For each domain you validate, you enable the certificate patterns it should be allowed to issue, whether it’s ExactDomain, Subdomains, or Wildcards. For example, if you validate internal.example.com and enable only Wildcards, an ACME client can request *.internal.example.com but a request for internal.example.com itself or api.internal.example.com is rejected. This enforcement happens at the endpoint level, before requests reach the ACM certificate authority, and you can validate multiple domains under a single endpoint, each with its own scope.

Centralized certificate visibility

Certificates issued through your ACME endpoints are registered with ACM. You can use the aws acm list-certificates command to see all your issued certificates.

IAM authorization, CloudTrail audit logging and observability

Endpoint management operations are authorized through IAM and logged to CloudTrail. You can use IAM policies to control which principals can create endpoints, generate EAB credentials, and manage domain constraints.

Best practices

For customers implementing ACME certificates for the first time, consider the following best practices for your organizations.

Segment endpoints along organizational or environment boundaries

The endpoint serves as a useful method of isolation for larger organizations. A large enterprise can create one endpoint per organizational boundary (business unit, subsidiary, or environment) instead of a single shared endpoint company-wide. Each endpoint has its own pre-approved domains and its own set of EABs, so a compromised credential in one business unit has no path to certificates in another.

However, weigh this against your operational overhead as well. A reasonable starting point is one endpoint per environment (dev, staging, andprod) within a business unit, expanding to per-business-unit endpoints only where compliance or organizational requirements call for it.

Manage EAB credentials securely

Anyone holding a validKeyIdandMacKeyfor an endpoint can obtain certificates for any domain pre-approved on that endpoint, so these credentials deserve the same handling you’d give an access key.

  • Avoid hard coding theMacKeywhere possible by using a secret store such as AWS Secrets Manager. Distribute it only to the ACME clients that you authorize to use the endpoint.
  • Set the expiration of the EAB to an acceptable level. While EAB supports long-lived credentials, not all scenarios require an indefinitely long EAB.
  • When creating the role for each EAB, adhere to concept of least privilege. Creating a role per EAB, rather than sharing a role across all bindings, can help reduce risk in your AWS environment.
  • Audit CreateAcmeExternalAccountBinding and GetAcmeExternalAccountBindingCredentials calls in CloudTrail separately. Because retrieving the actual key material is a distinct API call from creating the binding, alerting on retrieval events is a stronger signal of real credential distribution than binding creation alone.

Automate how EABs are associated with clients at runtime

Generate a unique set of EAB credentials for each client or environment rather than sharing one binding across multiple ACME clients. As you begin to scale with multiple endpoints, usesome of the following patterns to reduce operational toil.

  • Name each EAB and its bound IAM role after the client it belongs to (team, application, environment), so the binding’s purpose is obvious from DescribeAcmeExternalAccountBinding output alone, without cross-referencing a spreadsheet.
  • Store each client’s KeyId and MacKey under a secrets path scoped to that client (for example, a Secrets Manager path per team and environment), and let the client’s provisioning pipeline retrieve its own credentials.
  • In Kubernetes, use one ClusterIssuer or namespace-scoped Issuer per EAB rather than one shared issuer across teams. This keeps the client-to-EAB association explicit in cluster config, and lets you revoke one team’s access without touching anyone else’s.
  • For ephemeral infrastructure (build agents, autoscaled fleets), provision EAB credentials as part of your infrastructure-as-code or continuous integration and deployment (CI/CD) pipeline instead of a one-time manual handoff, so credential lifecycle tracks infrastructure lifecycle.

Monitor your deployment of ACME

ACME’s power is through automation, and organizations should monitor their ACME usage for anomalies.

  • Alarm on issuance failures, not just successes. At 45-day certificate validity, a silent renewal failure gives you far less runway to react than the months of time you might be used to with longer-lived certificates.
  • Test renewal automation before you depend on it. Force a manual renewal against a non-production endpoint and confirm your client, monitoring, and on-call runbooks behave as expected, before the CA/Browser Forum’s shortened validity windows turn a failed renewal into a disruptive event for your organization.

Availability and pricing

ACME support in AWS Certificate Manager is available today in all commercial AWS Regions and will be available in AWS GovCloud (US), the China Regions, and the AWS European Sovereign Cloud partitions at a later date. See the ACM pricing page for more information on ACME pricing.

Conclusion

The phased reduction in certificate validity can’t easily be solved without automation. ACME support in ACM gives you that automation through a standard protocol and standard tooling, while keeping the visibility and governance controls your security teams rely on from ACM.

To get started, see the AWS Certificate Manager documentation or follow the getting started guide.

If you have feedback about this post, submit comments in the Comments section below.


Anthony Harvey

Anthony Harvey

Anthony is a Senior Security Specialist Solutions Architect for AWS in the worldwide public sector group. Prior to joining AWS, he was a chief information security officer in local government for half a decade. With his public sector experience, he has a passion for figuring out how to do more with less and leveraging that mindset to enable customers in their security journey.

Chandan Kundapur

Chandan Kundapur

Chandan is a Principal Product Manager on the AWS Certificate Manager (ACM) team. With over 15 years of cybersecurity experience, he has a passion for driving PKI product strategy.

From 2 weeks to 2 minutes: Amazon Cognito launches Provisioned limits for self-service rate limit management

5 August 2026 at 19:17

Imagine preparing for your biggest sales event of the year, and you want to ensure your customer identity management service can handle the elevated traffic for carrying out application activities. For security teams, business leaders, and technologists managing identity infrastructure at scale, this scenario has been all too familiar. Whether you’re a CISO evaluating security controls, a CFO managing cloud costs, traditional support ticket processes for adjusting Amazon Cognito rate limits meant waiting 10–14 days for capacity increases, requiring teams to plan weeks in advance or rush to escalate.

Today, we’re announcing provisioned limits for Amazon Cognito, a capability that transforms how you manage authentication rate limits. This introduces a feature in the AWS Management Console for Amazon Cognito for on-demand capacity adjustments, working alongside the existing account-level maximum limits in AWS Service Quotas. Together, they give you self-service control over your authentication infrastructure so you can scale up for Black Friday (or similar sales events), scale down after tax season, and optimize costs with unprecedented precision. What once took up to 2 weeks now happens in minutes.

In this post, you’ll learn how provisioned limits work, the relationship between account-level maximums and provisioned capacity, the cost implications and optimization strategies, and step-by-step implementation guidance. This capability fundamentally changes how you approach authentication capacity planning.

Manual processes that can’t keep pace

Identity management services open the front door to your application. When users can’t sign in, everything else stops. Amazon Cognito offers extremely flexible limit management: customers can request adjustments as granular as 1 request per second (RPS) for as short as 1 day. As customer demand for faster, self-service adjustments grew, we identified opportunities to address the following challenges:

  • Support tickets required for each rate limit change
  • 10–14 day approval timelines for standard review and processing
  • Advance planning needed weeks ahead of anticipated traffic spikes

For businesses with seasonal traffic, like tax preparation services that see 90% of annual authentication volume in March and April, or ecommerce platforms preparing for Black Friday, these factors meant teams had to plan capacity decisions well in advance with limited ability to adjust in the moment.

Provisioned limits and account-level max limits

Starting July 6, 2026, Amazon Cognito introduced provisioned limits in the Amazon Cognito console. At the account level (per AWS Region, per account), you’ll find a Provisioned limits tab next to the User Pools tab. This gives you direct control over your authentication rate limits through two complementary mechanisms:

  • Provisioned limits (Amazon Cognito console) – Adjust your provisioned capacity up or down on-demand. Changes take effect immediately. You’re billed for the capacity you provision above the default limit, regardless of how much you use.
  • Account-level max limit (Service Quotas console) – Set your account’s ceiling, the maximum RPS your account is allowed to provision. Raising this ceiling doesn’t incur additional charges. Approximately 90% of requests are automatically approved within minutes. For larger limit increases (depending on the API category and Region), manual approval through AWS Support might still be required.

The following experience shows the end-to-end workflow of adjusting your provisioned limits and requesting a higher account-level max.

Figure 1: Provisioned limit experience workflow

Figure 1: Provisioned limit experience workflow

How they work together

Let’s use the UserCreation API as an example. The default limit is 50 RPS, and initially the provisioned limit is also 50 RPS—meaning billed capacity is 0 (no additional charge). The applied account-level max limit is also 50 RPS. So you have three values: default (50), provisioned limit (50), and account-level max (50).

  1. Start by going to the Amazon Cognito console and choosing User pools from the navigation pane.

    Figure 2: UserCreation with default values

    Figure 2: UserCreation with default values

  2. Choose Edit provisioned limit, to go to the Edit provisioned limit page with an input field for New provisioned limit. However, because the account-level max limit is 50 RPS, you can’t set the provisioned limit above 50. For example, if you want to provision 55 RPS, the console won’t allow it because 55 exceeds the current account max of 50.

    Figure 3: Editing the provisioned limit constraint constraint to more than the account-level max

    Figure 3: Editing the provisioned limit constraint constraint to more than the account-level max

  3. To set a higher limit, choose Request an increase. This takes you to the Service Quotas console, where you can choose Request increase at account level to request a higher account-level max, for example, 55 RPS. Most requests are automatically approved within minutes. At any time, you can check the status of the request using the Request history tab.

    Figure 4: Service Quotas page where the account-level max increase is requested and auto-approved

    Figure 4: Service Quotas page where the account-level max increase is requested and auto-approved

  4. After receiving approval, return to the Amazon Cognito console to edit your provisioned limit up to 55 RPS. Your billed capacity becomes 5 RPS (55 minus the 50 default).

    Figure 5: Provisioned after increasing the provisioned limit to 55 RPS, with billed capacity of 5 RPS.

    Figure 5: Provisioned after increasing the provisioned limit to 55 RPS, with billed capacity of 5 RPS.

This two-part model gives you precise control over both cost and capacity. Raising the account-level max in Service Quotas doesn’t incur additional charges—it only sets your ceiling. You are billed for what you provision in the Amazon Cognito console above the default, so you benefit from right-sizing your provisioned capacity to match expected demand. Raise your account max ahead of time to prepare for future scaling needs without incurring any cost. When the time comes, increase your provisioned limit to what you need, and scale back down after the event. You stop being charged for the extra capacity as soon as you reduce the provisioned limit. This applies equally to seasonal spikes, planned load tests, or unexpected viral growth—all self-service, all within minutes.

How the provisioned limits experience works

The provisioned limits experience introduces three key concepts that work together:

  • Default limit – The baseline rate included at no additional cost (for example, 50 RPS for UserCreation).
  • Provisioned limit – The capacity you actively request and reserve in the Amazon Cognito console. Because this capacity is reserved specifically for your account, it’s the chargeable dimension. You’re billed for any provisioned capacity above the default, regardless of how much you consume. For example, if the default is 50 RPS and you provision 80 RPS, you’re billed for 30 RPS even if your actual usage is only 60 RPS. If your provisioned capacity is 50 RPS (the default), your billed capacity is 0.
  • Applied account-level max limit – The ceiling managed through Service Quotas. This determines how high you can set your provisioned limit. Raising this ceiling doesn’t incur charges, it only unlocks the ability to provision higher capacity. Importantly, the Provisioned limits page displays each API category with its adjustability status. For example, UserCreation is marked Adjustable (shown earlier in Figure 5) and can be modified. However, UserList is marked Not adjustable, meaning the account-level max limit can’t be adjusted for that category. You can still see its default and provisioned limit on the page, but you can’t modify them. For adjustable categories, you will see the default limit, current provisioned limit, and billed capacity at a glance.
Figure 6: Provisioned limits overview with non-adjustable API categories.

Figure 6: Provisioned limits overview with non-adjustable API categories.

Multi-tenant SaaS considerations

For software as a service (SaaS) providers managing multiple tenants with varying throughput requirements, the UpdateProvisionedLimit API enables programmatic management of provisioned capacity. Teams using dedicated user pools per tenant, for example, can integrate this into their infrastructure-as-code pipelines to adjust provisioned limits per tenant tier. With provisioned limits, SaaS vendors can tier their capacity management per tenant, for example, provisioning higher capacity for enterprise-tier tenants and lower capacity for free-tier tenants, and adjust each tenant’s provisioned capacity independently through the API based on their service tier and demand patterns.

Conclusion

With provisioned limits, whether you’re preparing for peak shopping season, tax filing deadlines, or any other scaling event, you can now adjust provisioned limits to respond to your organization’s needs on demand. The separation between the account-level max (in Service Quotas) and the provisioned limit (in the Amazon Cognito console) gives you full control to plan ahead, respond to demand changes in minutes, and optimize costs on your own terms.

Get started

The provisioned limits experience for Amazon Cognito user pools launched on July 6, 2026, and is available across all AWS Regions where Amazon Cognito is supported. To get started:

  1. Review your current authentication traffic patterns using Amazon CloudWatch metrics to understand your baseline
  2. Set up CloudWatch alarms at 70% and 85% of your current rate limits
  3. Ensure your team has appropriate AWS Identity and Access Management ( IAM) permissions for both Service Quotas and the Provisioned limits tab in the Amazon Cognito console
  4. Raise your account-level max in Service Quotas based on your demand expectations
  5. Use the Amazon Cognito console Provisioned limits tab to adjust capacity up or down as needed

Resources:

Need help? Contact your AWS account team or visit AWS Support for assistance with planning your rate limit strategy.

If you have feedback about this post, submit comments in the Comments section below.


Kiran Dongara

Kiran is an Enterprise Solutions Architect at AWS, primarily supporting Retail, Restaurant, and CPG customers. His primary focus is application identity within the IAM domain. His expertise includes deep technical understanding across technical and industry domains, which he integrates to design scalable and efficient architectures using best practices. When not working, Kiran prioritizes family time, nature walks, and cycling.

Howie Li

Howie Li

Howie Li is a Product Manager at Amazon Web Services, where he strives to make authentication straightforward by default. Outside of work, Howie enjoys exploring cultures and food through travels and making new ice cream flavors inspired by them.

Secure your npm and pip package updates in Amazon Linux

29 July 2026 at 16:53

If you use and install packages from npm or PyPI, the first hours after a package is published are the riskiest because scanners can’t analyze packages before publication. Recent supply chain events affecting NodeJS and Python packages have been detected and removed within hours. However, while those packages were available to the general public, it’s possible that they were installed by users, creating the potential for a security incident. As you will see from the data that follows, if users had waited 1 day before accessing those packages, none of the recent supply chain security events would have had an impact.

In this post, I show you a one-line configuration that you can use to eliminate this exposure in your environment: a dependency cooldown for npm and pip. This change tells your package manager to skip versions published in the last 24 hours, giving the security community time to detect and remove unexpected packages before they reach your systems. These settings secure the default setup. There’s another use case of package updates: receiving security fixes to address security risks. This process involves updating packages to a more recent version. I also show you how to override the cooldown configuration so you can install the latest security patches while newly installed package updates are delayed. We recommend that you assess the severity of code defects and apply security fixes if there’s known risk. Handling security fixes based on their severity—and how to specify SLAs for these fixes based on severity—is beyond the scope of this blog post.

Background: Two risks pull in opposite directions

Software delivered by Amazon Linux packages go through review by Amazon package maintainers and pass guardrails before release. Open source software is developed and maintained with similar processes and guardrails. The npm and PyPI registries have open publishing access and don’t enforce reviews. Unexpected packages are potentially added to the registries because of risks like impersonation or stolen credentials. You’re caught between two risks: older software accumulates unpatched vulnerabilities, while new packages potentially contain unexpected vulnerabilities that haven’t been detected yet. The best approach is to stay current without adopting the newest releases immediately, while applying recommended security fixes. The following diagram illustrates the relation between the two types of risks in an abstract way, where the supply chain risk is highest immediately after a package is published, because unexpected updates can potentially bypass guardrails. After a package is published, auditing can review it and identify potential defects over time. If no security fixes are applied, the risk of all the code defects adds up.

Figure 1: Software risk over lifetime. Unpatched vulnerabilities risk increases over time. Very recent software also carries more supply chain risk.

Figure 1: Software risk over lifetime. Unpatched vulnerabilities risk increases over time. Very recent software also carries more supply chain risk.

The problem: The first day presents the highest risk

Supply chain events follow a consistent pattern. An unexpected author publishes an unexpected package or package version and waits for automated systems and users to pull it in. Security researchers and automated scanners typically detect and remove these packages within hours, but by then, systems have been exposed to the risk.

Datadog’s 2026 State of DevSecOps report found that 54% of JavaScript applications install at least one dependency within a day of its release. That’s the time window that presents the highest supply chain risk. Recent events show how fast detection happens:

Event Exposure window
Nx s1ngularity (Aug 2025) 4–5 hours
axios (Mar 2026) 2–3 hours
Bitwarden CLI (Apr 2026) 93 minutes
TanStack (May 2026) 30 minutes
node-ipc (May 2026) less than 24 hours

The solution: Skip packages published today

A dependency cooldown tells your package manager to skip recently published versions. If a version hasn’t existed on the registry for the configured timespan, for example, 1 day, it won’t be installed, giving the security community time to detect and remove unexpected versions.

A 1-day cooldown blocks each event listed in the preceding table. Notably, several of these events produced valid provenance attestations and passed build verification. These provenance checks alone didn’t stop them. A cooldown works independently of authorization mechanisms, because it blocks by age rather than by trust.

Both npm (v11.10.0+) and pip (v26.1+) support cooldowns . Amazon Linux 2023 ships these packages in NodeJS 24 and Python 3.14 since release 2023.11.20260608.

If you use lockfile-based installations through npm ci or pip install -r requirements.txt with pinned versions, you won’t pull latest package updates. The cooldown doesn’t apply to those installations. The cooldown only affects resolution of new or updated packages. See the Lockfile-based installs and the cooldown section for details.

Prerequisites

To implement the following solution, you first need to have the following prerequisites in place:

  • Node.js 24 with npm 11.10.0 or later (in nodejs24-24.14.1-1.amzn2023.0.1 or later).
  • Python 3.14 with pip 26.1 (in python3.14-pip-26.1.1-1.amzn2023.0.1 or later)
  • pip-audit (tool to scan python packages required for defect-based override scripts). Use python3.14 -m pip install pip-audit to install.

Future versions of Node.js and Python will bring new commands. The following tool commands work for Amazon Linux 2023 with Node.js 24 and Python 3.14. The provided commands target specific package versions. Adjust the commands if you use later releases.

To set up the npm cooldown

  1. Create the global configuration directory, depending on your NodeJS version.
    sudo mkdir -p /usr/lib/nodejs24/etc
  2. Add the npm configuration file with the cooldown setting.
    sudo npm-24 config set min-release-age 1 --location=global
  3. Check that the cooldown is active by running the next command.
    npm-24 config list

You will see before = "<timestamp from 24 hours ago>" in the output, confirming npm converted the 1-day cooldown into a date filter.
For more information, see the npm min-release-age documentation.

To set up the pip cooldown

  1. Create the system-wide pip configuration file with the cooldown setting.
    sudo python3.14 -m pip config set --global global.uploaded-prior-to P1D
  2. Verify the configuration (for Python 3.14 and pip 26.1+).
    python3.14 -m pip config list

You will see global.uploaded-prior-to='P1D' in the output.

This configuration is safe to deploy immediately, because older pip versions (25.x) silently ignore the setting.

To install a package’s latest version without cooldown

What if you want to install the latest version of a package, for example to receive security fixes? The following sections describe how to override the flag using the tool command line. To identify which packages need urgent updates, run the appropriate audit command for your package manager.

npm auditor python3.14 -m pip_audit

For npm packages

Install the package with the cooldown override.
npm-24 install <package-name> --min-release-age=0

For pip packages

Install the package with the cooldown override.
python3.14 -m pip install <package-name> --uploaded-prior-to="P0D"

Update packages that need urgent updates

We recommend that you apply security fixes for packages that have known security risks. You don’t need to turn off the cooldown entirely to apply security fixes. Use the audit tools to identify packages with known issues, then override the cooldown for only these packages.

Prerequisites: Ensure you have Python 3 and pip-audit installed (python3.14 -m pip install pip-audit).

Important: These scripts demonstrate the concept. For production use, add error handling, logging, and testing. Review packages before updating them in automated pipelines.

For npm packages

The following script demonstrates the required steps to identify npm packages with a known security fix. The npm audit command prints these packages as JSON. Next, packages in this list are updated with an npm install command, where their cooldown is overridden so that the latest version is picked up.

npm audit --json | python3 -c "
import json, sys, subprocess
data = json.load(sys.stdin)
for pkg in data.get('vulnerabilities', {}):
    subprocess.run(['npm-24', 'install', f'{pkg}@latest', '--min-release-age=0'])
"

For pip packages

The following script demonstrates the required steps to identify pip packages with a known security fix. The pip_audit command prints these packages as JSON. Next, all packages in this list are updated with an pip install command that overrides the cooldown so that the latest version can be picked up.

python3.14 -m pip_audit --format=json | python3.14 -c "
import json, sys, subprocess
from packaging.version import Version
data = json.load(sys.stdin)
for dep in data.get('dependencies', []):
    pkg = dep['name']
    vulns = dep.get('vulns', [])
    if not vulns:
        continue
    fix_versions = [v for vuln in vulns for v in vuln.get('fix_versions', [])]
    if not fix_versions:
        print(f'{pkg}: vulnerable but no fix published, skipping')
        continue
    fix = max(fix_versions, key=Version)
    print(f'Updating {pkg} -> {fix}')
    subprocess.run(['python3.14', '-m', 'pip', 'install', f'{pkg}=={fix}', '--uploaded-prior-to=P0D'])
"

Lockfile-based installs and the cooldown

If you use npm ci or pip install -r requirements.txt with pinned versions, the cooldown doesn’t apply. These commands install what the lockfile specifies, regardless of package age. The cooldown only affects resolution of new or updated packages.

Industry adoption: Cooldowns are now used across PyPI and NodeJS

Major package managers and enterprises have started to adopt dependency cooldowns. As of May 2026, several popular package management tools now include cooldown features: pnpm (a fast Node.js package manager), Renovate (an automated dependency update tool), and StepSecurity (a supply chain security platform).

  • pnpm 11 ships with minimumReleaseAge enabled by default. It’s one of the first major package manager to make cooldowns opt-out rather than opt-in.
  • Renovate’s config best-practices preset has included a 3-day npm cooldown since 2025 and is widely adopted across enterprises.
  • StepSecurity Secure Registry uses a configurable cooldown period for enterprise customers. StepSecurity recommends a 10 day delay as default.

How AWS is helping protect the open source supply chain

AWS scans upstream package registries to catch unexpected packages before they reach customers.

Unexpected packages are typically caught within hours of publication. A 1-day cooldown ensures you don’t install them during that detection window.

Recommendations

To secure your Amazon Linux 2023 configuration:

  1. Set a 1-day cooldown for npm and pip as shown in the preceding sections. External registries don’t have human review, so give the defenders time to catch problems.
  2. Override when needed for urgent security patches using the per-command flags.
  3. Run npm audit or pip_audit regularly to identify packages that need immediate attention.

Set up the cooldown with one line of configuration, and the protection is immediate.

Conclusion

By implementing the solutions presented in the post, you secure your npm and PyPI environment from most instances of unexpected code. The update delay of 1 day protects your environment, while still allowing to apply the latest security fixes. To learn about how to protect your environment further, see the following resources:

If you have feedback about this post, submit comments in the Comments section below.


Norbert Manthey

Norbert Manthey

Norbert is a Security Engineer in the Amazon Linux team, focusing on proactive security across hypervisors and operating systems in Amazon EC2. His work includes hardening operating system defaults, detecting code issues early through static and AI-driven analysis, and improving supply chain security for packages shipped with Amazon Linux. Norbert advocates for automating these process improvements, injecting them into the software development lifecycle, and shifting left.

Accelerating AWS Network Firewall troubleshooting with AWS DevOps Agent

24 July 2026 at 21:54

When an administrator introduces a rule change in AWS Network Firewall and network connectivity is disrupted, pinpointing the cause requires inspecting multiple points in the traffic path. The firewall gives you stateless and stateful rule engines, domain rules, and routing to the firewall endpoint inside your Amazon Virtual Private Cloud (Amazon VPC). A network drop looks the same from the workload no matter where it started. Isolating the cause means correlating the alert and flow logs with the firewall configuration, route tables, and recent API calls in AWS CloudTrail that might have changed them. That manual correlation is exactly where AWS DevOps Agent helps, accelerating root cause analysis so you can restore connectivity in minutes instead of hours.

AWS DevOps Agent does that correlation for you. As your always-available operations teammate, it resolves and proactively prevents operational issues across AWS, multicloud, and on-premises environments. When an Amazon CloudWatch alarm triggers, it reaches the agent through a webhook. The agent then reads the firewall configuration and logs through AWS APIs, ties the drop to recent API activity, and returns a root cause with a mitigation plan you review before you apply it.

This post connects CloudWatch monitoring to DevOps Agent. It walks through three Network Firewall failures from end to end. The first is a domain deny list blocking a legitimate endpoint. The second is a stateless rule priority misconfiguration. The third is an asymmetric cross Availability Zone (AZ) routing drop. Each maps to a different layer, so each leads down a different investigation path. An AWS Cloud Development Kit (AWS CDK) app deploys the whole environment in your own account so you can reproduce each failure and follow along.

The sample workload

As part of this blog post, we provide a CDK stack that deploys both the AWS DevOps Agent Space and a sample workload used to walk through three separate troubleshooting scenarios. A single t3.micro instance in a protected subnet checks its connectivity to a test endpoint on a continuous loop and publishes results to CloudWatch. Traffic takes the internet egress path through Network Firewall, the NAT gateway, and the internet gateway, so the firewall can intercept or drop it. After completing the walkthrough, you can apply the same troubleshooting techniques with DevOps Agent against your own Network Firewall deployments.

The test endpoint runs in a separate VPC deployed by the same CDK app. It serves HTTPS on port 443 and TCP on port 9142, giving each scenario a different protocol layer to exercise: Scenario 1 targets a TLS connection on 443 (matched by Server Name Indication), Scenario 2 targets a TCP connection on 9142, and Scenario 3 exercises the whole egress path.

A live status page shows one card per scenario plus the network topology. The whole stack deploys from a single CDK app across two Availability Zones, each with a firewall endpoint and NAT gateway, which is what makes Scenario 3 possible.

As shown in the following figure, the egress data path runs from the workload through Network Firewall and the NAT and internet gateways to the test endpoint. The alarm pipeline runs from CloudWatch through Amazon Simple Notification Service (Amazon SNS) and the webhook AWS Lambda function to DevOps Agent.

Figure 1: The sample workload

Figure 1: The sample workload

To use this with your own workload, you need a CloudWatch alarm that detects the connectivity problem and the webhook pipeline (SNS topic and Lambda function) that delivers it to DevOps Agent. The agent reads your firewall configuration, logs, and CloudTrail through AWS APIs, so no additional instrumentation is needed on the firewall side.

Prerequisites

To follow along with this post, you need:

Deploy the sample workload

Clone the project and deploy it into us-east-1 with one command (set awsRegion to use another AWS Region).

git clone https://github.com/aws-samples/sample-accelerating-aws-network-firewall-troubleshooting-with-aws-devops-agent.git
cd sample-accelerating-aws-network-firewall-troubleshooting-with-aws-devops-agent
bash scripts/deploy.sh

The script checks prerequisites, installs dependencies, compiles and tests, and bootstraps the CDK if needed. It then deploys all the stacks from a clean baseline and prints the outputs, including the status-page URL and sign-in details.

  1. Open the status-page link (an https://<random-id>.cloudfront.net address).
  2. Sign in using the username and password provided from the CDK output and confirm all three cards show the green Healthy status.
  3. Keep the page open while you run the scenarios.

Connect AWS DevOps Agent

To connect AWS DevOps Agent to the alarm pipeline

  1. In the AWS DevOps Agent console, open the nf-devops-agent-space Agent Space created by the CDK deployment.
  2. Configure the DevOps Agent webhook and download the CSV file with the webhook URL and signing secret.
  3. On the status page, choose Configure webhook, paste the URL and signing secret, and save. The page writes them to the nf-devops-agent-webhook-credentials AWS Secrets Manager secret, so there is no AWS CLI or console step. Until you set it, the bridge Lambda function sees a placeholder and skips delivery.
  4. Verify the path before you run a scenario. In the Lambda console, open nf-devops-agent-webhook and use the Test tab with this event.
    {
      "Records": [
        {
          "Sns": {
            "Message": "{\"AlarmName\":\"TEST-webhook-verification\",\"AlarmDescription\":\"[TEST] Webhook integration test - not a real alarm.\",\"NewStateValue\":\"ALARM\",\"NewStateReason\":\"[TEST] Manual webhook connectivity test. Safe to ignore.\",\"Region\":\"us-east-1\"}"
          }
        }
      ]
    }
  5. A 200 response confirms the path, and a test investigation appears in the DevOps Agent Operator Web App view.

How the alarm pipeline works

Every scenario reaches DevOps Agent the same way. A CloudWatch alarm moves to ALARM and notifies the SNS topic. Amazon SNS invokes a Lambda function. The function reads the webhook URL and signing secret from Secrets Manager, signs an alarm payload, and POSTs it to the DevOps Agent webhook (as shown in Figure 1). Amazon SNS also provides delivery retries, fan-out to other subscribers, and cross-account publishing.

  • Prebuilt Network Firewall metric (Scenario 1) – Alarm-1 watches the DroppedPackets metric, summed across the stateful streams, and triggers when drops rise above a baseline threshold. This requires no workload or custom metric and works on an already-deployed firewall. However, it only tells you that the firewall is dropping packets, not which rule is responsible.
  • Application health metric (Scenarios 2 and 3) – Alarm-2 and Alarm-3 watch a custom metric from a connectivity check. Use this for an alarm tied to user-facing impact or to tell one traffic path from another, which requires running a component that emits the metric.
Alarm Source Triggers when
Alarm-1 Native AWS/NetworkFirewall DroppedPackets The firewall’s dropped-packet count rises above the baseline
Alarm-2 Custom application health metric The port 9142 (TCP) connectivity check to the test endpoint is being dropped
Alarm-3 Custom application health metric The cross Availability Zone connectivity check is being dropped

Run the scenarios

Work through each of the scenarios one at a time, following the same cycle. Interrupt network connectivity, watch the alarm trigger, let DevOps Agent investigate, apply the recommended fix, and confirm recovery before moving on.

The status-page cards follow the live CloudWatch alarm state. A card shows a green dot and the word Healthy when its alarm is clear, and a red dot and the word DROPPED when its alarm triggers. In the DROPPED state the card also adds a Condition: line describing what’s being dropped, which isn’t shown when the card is healthy. Network Firewall applies changes to new flows, so a change shows within a minute or two. Recovery comes from the mitigation DevOps Agent recommends, which you review and apply.

Scenario 1. Domain deny list blocking a legitimate endpoint

At baseline, the rg-domain Suricata domain rule group denies only an unused placeholder, so the test endpoint stays reachable. The rule group inspects the TLS Server Name Indication (SNI) on each outbound connection and drops any that matches a denied domain. The exact rule syntax and console steps follow.

To add the domain deny rule

  1. Go to the Amazon VPC console.
  2. In the navigation pane, under Network Firewall, choose Network Firewall rule groups.
  3. Choose the rg-domain rule group to open its details page.
  4. In the Rules section, choose Edit.
  5. The rules box already contains two baseline placeholder rules (they match blocked.placeholder.invalid, so nothing real is denied). Leave those in place. Find the <app-endpoint-dns> value for Scenario 1 in the deployment script output (a Nework Load Balancer (NLB) DNS name such as NfTest-AppNl-a1b2C3dEf4G5-1234abcd5678efgh.elb.us-east-1.amazonaws.com). On a new line below the existing rules, add a drop rule that matches that DNS name on the TLS SNI, then choose Save.
    drop tls $HOME_NET any -> $EXTERNAL_NET any (ssl_state:client_hello; tls.sni; content:"<app-endpoint-dns>"; startswith; nocase; endswith; msg:"S1 domain denylist"; flow:to_server, established; sid:2000002; rev:1;)
  6. After saving, the rules box holds all three lines. The two placeholders remain, plus the new drop rule for the endpoint DNS name (note the distinct sid 2000002).
Figure 2: Scenario 1 – Firewall rule change blocking the connection

Figure 2: Scenario 1 – Firewall rule change blocking the connection

What happens. The workload’s HTTPS check to the test endpoint times out, the “AWS/NetworkFirewall DroppedPackets metric climbs above baseline, and Alarm-1 moves to ALARM. The Scenario 1 card reads DROPPED (with the condition Firewall dropping the monitored domain on its allow/deny rules), while the Scenario 2 and Scenario 3 cards stay Healthy (Figure 3). On the topology, the alarm pipeline from CloudWatch through Amazon SNS and Lambda to DevOps Agent and the workload-to-firewall inspect lines both turn amber, which the legend defines as collateral / alarm active, because the packets are now dropped at the firewall. To demonstrate the resulting failure, the HTTPS · SNI line from the internet gateway to the test endpoint is shown in red, which the legend defines as dropped (root cause).

Figure 3: Scenario 1 active – Traffic blocked at the firewall

Figure 3: Scenario 1 active – Traffic blocked at the firewall

Let DevOps Agent investigate. The agent runs several lines of investigation in parallel and correlates them:

  1. Reads the DroppedPackets metric and correlates the spike with a simultaneous drop in passed packets, confirming the firewall is actively blocking traffic.
  2. Reads the ALERT log and finds the workload’s TLS connections to the test endpoint blocked by the S1 domain denylist rule.
  3. Compares the current state against a baseline window, where the same endpoint was reachable with no alerts, which shows the block is new.
  4. Searches CloudTrail and surfaces the UpdateRuleGroup call that added the deny rule, identifying the user, role, and timestamp approximately one minute before the drops began.
  5. Reports the root cause as that manual rule-group change. Recommends removing the deny entry or adding an allow exception and enabling FirewallPolicyChangeProtection to prevent unauthorized changes.
  6. Presents this as a plan you review and apply, not an automatic change.

In the DevOps Agent Operator Web App view, the agent first restates the Alarm-1 trigger and confirms the firewall is dropping packets above the threshold (Figure 4).

Figure 4: Scenario 1 – The symptom

Figure 4: Scenario 1 – The symptom

Next, the agent identifies the root cause: a manual update to the rg-domain rule group that added a domain deny rule (SID 2000002) shortly before the alarm fired, blocking TLS connections to the ELB endpoint (Figure 5).

Figure 5: Scenario 1 – The root cause

Figure 5: Scenario 1 – The root cause

Finally, the agent presents a mitigation plan, recommending you remove the problematic deny rule (SID 2000002) to restore connectivity (Figure 6).

Figure 6: Scenario 1 – The mitigation plan

Figure 6: Scenario 1 – The mitigation plan

Note: In a real-world environment, this type of rule typically exists for a reason. Before removing it, verify whether it was intentional but scoped too broadly. If so, refine the rule to block only unauthorized endpoints rather than removing it entirely.

Confirm recovery. Apply the change the agent recommends. After the deny entry is gone, DroppedPackets falls back to baseline, Alarm-1 clears, and the card returns to green. Move on to Scenario 2.

Scenario 2. Stateless rule priority misconfiguration

At baseline, the rg-stateless-priority stateless rule group keeps the allow rule at priority 100 and the drop rule at 200 for the test class, TCP destination port 9142. The workload opens a TCP connection to the test endpoint on this port. Lower priority numbers evaluate first, so the allow rule wins. This scenario uses port 9142 instead of 443 to demonstrate a stateless rule, which matches on the packet’s 5-tuple (protocol, ports, addresses) rather than application content.

Introduce the change. Invert the two rule priorities so the drop rule evaluates before the allow rule. This is the kind of change a rushed rule edit can introduce.

To invert the stateless rule priorities

  1. Go to the Amazon VPC console.
  2. In the navigation pane, under Network Firewall, choose Network Firewall rule groups.
  3. Choose the rg-stateless-priority rule group to open its details page.
  4. In the Rules section, choose Edit.
  5. Raise the (Action: Pass) rule’s priority number so it sits after the (Action: Drop) rule, then choose Save. For example, change the (Action: Pass) rule from 100 to 300 (any number higher than the drop rule’s 200 works). You only need to move one rule, and using 300 avoids a clash with the drop rule that already sits at 200. Network Firewall evaluates the lowest priority number first, so the (Action: Drop) rule at 200 now wins for this traffic class, ahead of the (Action: Pass) rule at 300.
Figure 7: Scenario 2 – Rule priority change blocking the traffic class

Figure 7: Scenario 2 – Rule priority change blocking the traffic class

What happens. The drop rule now wins, the TCP connection to the test endpoint on port 9142 times out, the StatelessRuleFailures metric climbs above baseline, and Alarm-2 moves to ALARM. The Scenario 2 card reads DROPPED (with the condition Stateless rules dropping the monitored traffic class), while the Scenario 1 and Scenario 3 cards stay Healthy (Figure 8). On the topology, the alarm pipeline from CloudWatch through Amazon SNS and Lambda to DevOps Agent and the workload-to-firewall inspect lines both turn amber, which the legend defines as collateral / alarm active, because the packets are now dropped at the firewall. To demonstrate the resulting failure, the TLS :9142 line from the internet gateway to the test endpoint is shown in red, which the legend defines as dropped (root cause).

Figure 8: Scenario 2 active

Figure 8: Scenario 2 active

Let DevOps Agent investigate. A stateless drop happens before traffic reaches the stateful inspection engine, so it produces no ALERT log entries. The agent turns to configuration and flow logs instead:

  1. Reads the stateless rule group state and finds the drop rule at the lower priority number, ahead of the pass rule, so the drop evaluates first.
  2. Reads the flow logs and sees passed packets drop to zero within a minute of the change.
  3. Searches CloudTrail and surfaces the UpdateRuleGroup call that inverted the priorities, identifying the user, role, and timestamp about a minute before the alarm.
  4. Reports the root cause as that priority inversion. Recommends removing the redundant drop rule and managing the rule group through infrastructure-as-code (IaC) to prevent manual misconfigurations.
  5. Presents this as a plan you review and apply, not an automatic change.

In the DevOps Agent Operator Web App view, the agent first restates the Alarm-2 trigger and confirms that a workload connectivity health check is failing because the firewall’s stateless rules are dropping egress (Figure 9).

Figure 9: Scenario 2 – The symptom

Figure 9: Scenario 2 – The symptom

Next, the agent identifies the root cause, using the rule-group state and CloudTrail to pinpoint the conflicting DROP/PASS rules, where the new DROP rule’s lower priority number makes it match first (Figure 10).

Figure 10: Scenario 2 – The root cause

Figure 10: Scenario 2 – The root cause

Finally, the agent presents a mitigation plan, recommending you remove the conflicting DROP rule at priority 200 to restore traffic flow (Figure 11).

Figure 11: Scenario 2 – The mitigation plan

Figure 11: Scenario 2 – The mitigation plan

Confirm recovery. Apply the change the agent recommends. After the allow rule is ahead of the drop rule again, Alarm-2 clears and the card returns to green. Move on to Scenario 3.

Scenario 3. Asymmetric cross Availability Zone routing drop

At baseline, the protected subnet in each Availability Zone routes its egress through the firewall endpoint in that same Availability Zone , and the matching return route uses that same endpoint. One endpoint sees both directions of the flow, so the stateful engine completes the handshake. The workload runs in the protected subnet in us-east-1a (CIDR 10.0.4.0/24), so at baseline its egress and its return both use the us-east-1a firewall endpoint.

Introduce the change. Make the flow asymmetric by sending egress out one Availability Zone endpoint while the return comes back through the other. This takes two route edits, and both are required. With only the first edit the flow can still complete, so the alarm will not trigger until both are saved. It makes no firewall-policy change, mirroring a real multi-Availability-Zone routing mistake.

To create asymmetric cross Availability Zone routing

  1. Go to the Amazon VPC console and choose Route tables in the navigation pane.
  2. Flip the egress. Select the NfNetworkStack/SampleVpc/protectedSubnet1 route table (the us-east-1a protected subnet, where the workload runs). On the Routes tab, choose Edit routes. Its 0.0.0.0/0 route currently targets the us-east-1a firewall endpoint. For the target, choose Gateway Load Balancer Endpoint and select the us-east-1b firewall endpoint, then choose Save changes.
  3. Move the return. Select the NfNetworkStack/SampleVpc/publicSubnet2 route table (the us-east-1b public subnet, where egress now exits). Choose Edit routes, then Add route. For the destination enter the workload CIDR 10.0.4.0/24. For the target, choose Gateway Load Balancer Endpoint and select the us-east-1a firewall endpoint. Choose Save changes.

After both edits, a flow’s egress leaves through the us-east-1b endpoint while its return is directed to the us-east-1a endpoint. Neither endpoint sees the whole flow.

Figure 12: Scenario 3 routing change breaking the flow’s symmetry

Figure 12: Scenario 3 routing change breaking the flow’s symmetry

What happens. A new connection leaves through one endpoint. Its return arrives at the other endpoint, which never saw the connection open, so the handshake fails. Unlike Scenarios 1 and 2, this affects the whole subnet, so all egress stops and Alarm-2 and Alarm-3 both move to ALARM. The AWS/NetworkFirewall DroppedPackets alarm (Alarm-1) stays quiet because no endpoint is making a drop decision. The flow is lost to asymmetric routing rather than counted as a firewall drop. This is why monitoring application connectivity matters. A routing fault is invisible to the firewall’s own drop counter. On the status page, the Scenario 2 card reads DROPPED (with the condition “Stateless rules dropping the monitored traffic class”) and the Scenario 3 card reads DROPPED (with the condition Return traffic dropped by asymmetric cross-Availability-Zone routing), while the Scenario 1 card stays Healthy (Figure 13). On the topology, the alarm pipeline from CloudWatch through Amazon SNS and Lambda to DevOps Agent and the workload-to-firewall inspect lines both turn amber, which the legend defines as collateral / alarm active, while the egress path from the firewall through the NAT gateway and the TLS :9142 and HTTPS · routing lines to the test endpoint turn red, which the legend defines as dropped (root cause).

Figure 13: Scenario 3 – The status page during a path-wide outage

Figure 13: Scenario 3 – The status page during a path-wide outage

Let DevOps Agent investigate. Both Alarm-2 and Alarm-3 fire in the same datapoint. DevOps Agent recognizes them as linked and merges them into a single investigation:

  1. Reads the flow logs and sees bidirectional TLS connections stop abruptly, with only one-way traffic remaining and no flows reaching the established state.
  2. Reads the firewall metrics and sees received and passed packets shift from one Availability Zone to the other at the moment of the change.
  3. Calls DescribeRouteTables and finds the egress route pointing at one Availability Zone firewall endpoint while the return route points at the other.
  4. Searches CloudTrail and surfaces the ReplaceRoute and CreateRoute calls by the same user, about a minute before both alarms fired.
  5. Reports the root cause as that asymmetric routing change. Recommends restoring symmetric same-Availability-Zone routing so egress and return traverse the same endpoint.
  6. Presents this as a plan you review and apply, not an automatic change.

A mitigation plan is a recommendation you review, not an automatic change, and the right fix depends on the intended design. Restoring symmetric routing can mean sending the workload subnet’s egress back through its own-Availability-Zone firewall endpoint (this sample’s architecture) or, in a design that doesn’t inspect this path, back through a NAT gateway. The agent infers a plausible target from what it can observe, so review the specific route it proposes against your intended topology before you apply it. (Connecting your pipeline or infrastructure-as-code, covered in the next section, lets the agent recommend the target that matches your design.)

In the DevOps Agent Operator Web App view, the agent restates the Alarm-3 (AsymmetricFlowFailures) trigger and confirms the workload’s egress to a monitored endpoint is being blocked by the Network Firewall (Figure 14).

Figure 14: Scenario 3 – The symptom

Figure 14: Scenario 3 – The symptom

Next, the agent identifies the root cause: manual route table changes that created cross-AZ asymmetric routing through the network firewall, breaking its symmetric routing requirement (Figure 15)

Figure 15: Scenario 3 – The root cause

Figure 15: Scenario 3 – The root cause

Finally, the agent presents a mitigation plan, recommending you restore symmetric routing by pointing protectedSubnet1‘s default route back to the same Availability Zone firewall endpoint, so one endpoint sees both directions of the flow again (Figure 16).

Figure 16: Scenario 3 – The mitigation plan

Figure 16: Scenario 3 – The mitigation plan

Confirm recovery. Apply the change the agent recommends, after checking the route target matches your intended design. After the workload subnet’s egress and return use the same Availability Zone firewall endpoint again, the control probe recovers, the alarms clear, and every card returns to green.

Further considerations

In production a single change can trigger several alarms at the same time, as Scenario 3 shows. DevOps Agent links related investigations and works them as one, so you review a single root cause. You can validate the linked findings or unlink an alarm to investigate it independently. If you would rather collapse alarms before they reach the agent, you can add correlation logic in the bridge Lambda function, buffering and grouping by firewall. You can also add email, Amazon Simple Queue Service (Amazon SQS), or HTTP subscribers to the SNS topic, or add the webhook Lambda function to a topic you already run. DevOps Agent produces a mitigation plan but does not change your environment on its own.

You can also give the agent more to work with. DevOps Agent connects to source repositories and CI/CD pipelines, integrating with GitHub (including GitHub Enterprise Server and GitLab Self-Managed through a private connection). It can associate AWS resources with deployments of AWS CloudFormation, AWS CDK, Amazon Elastic Container Registry (Amazon ECR) images, and Terraform. With deployed configuration and recent deployment events in view, the agent correlates the disruption against the change that introduced it and recommends a fix matching your intended design. For this sample, that means recommending the workload subnet’s own Availability Zone firewall endpoint rather than a generic symmetric path.

DevOps Agent also supports proactive incident prevention. It analyzes patterns across past investigations and delivers recommendations to prevent similar issues from recurring, including governance recommendations that strengthen deployment processes and pipeline controls. For Network Firewall rule changes, this means the agent can recommend guardrails for your CI/CD pipeline based on the classes of misconfigurations it has already resolved. You can access these recommendations through the Improvements page in the DevOps Agent Operator Web App.

Clean up

Clean up the environment with one command.

bash scripts/destroy.sh

It reverts any active scenario, runs cdk destroy for all stacks, and sweeps for stragglers by the Project = nf-devops-agent tag. The main cost drivers are the two Network Firewall endpoints, the NAT gateways (one in the main VPC for each Availability Zone, one in the test-endpoint VPC), and the test endpoint’s load balancers. Each of these bills at an hourly rate for as long as it’s provisioned, whether or not traffic is flowing, so a stack left running continues to accrue charges around the clock even while idle. Running the scenarios and tearing the stack down the same day limits the cost to a few active hours rather than days of idle hourly charges.

Conclusion

In this post, we showed you how AWS DevOps Agent accelerates troubleshooting for three common network firewall connectivity issues. The first was a domain deny list. The second was a stateless priority inversion. The third was an asymmetric cross-AZ routing drop. For each one, DevOps Agent investigated the drop and returned a root cause with a mitigation plan you approve before applying. The first scenario triggered on a prebuilt Network Firewall metric, and the other two on application health metrics. That shows both ways to alarm on a firewall problem through one pipeline.

The pattern isn’t specific to Network Firewall. The same flow fits any service that emits CloudWatch metrics and logs, such as AWS WAF, security groups, and network ACLs. Clone the sample repository to explore the solution, then apply what you learn to your own firewall, application, and alarms. For more details, see the AWS Network Firewall Developer Guide and the AWS Network Firewall pricing page. Start with the Getting Started with AWS DevOps Agent guide to connect your first webhook.

Salman Ahmed

Salman is a Senior Technical Account Manager at AWS, specializing in helping customers design, implement, and optimize their AWS environments. He combines deep networking expertise with a passion for exploring emerging technologies to help organizations get the most out of their cloud investments. Outside of work, he enjoys photography, traveling, and watching his favorite sports teams.

Do more with AWS WAF labels using dynamic label interpolation

21 July 2026 at 19:03

AWS WAF classifies web traffic by attaching metadata to each request it evaluates. Managed rule groups such as AWS WAF Bot Control and AWS WAF Fraud Control account takeover prevention (ATP) attach labels that describe what they found. A label can record that a request came from a known bot category or that it matched a credential-stuffing pattern. You can forward that metadata to your origin as request headers, which gives your backend visibility into the decisions AWS WAF made at the edge. You can also use labels to build tiered policies: a low-confidence bot signal might trigger a CAPTCHA challenge, whereas a high-confidence signal blocks the request outright.

With the AWS WAF AI Activity Dashboard, launched February 24, 2026, Bot Control now identifies more than 650 bots and agents, including search engine crawlers, data collectors, AI assistants, and large language model (LLM) training crawlers, which is ever increasing over time. In an earlier post, we showed how to group Bot Control labels into confidence levels and use them to drive adaptive user experiences in your application. That approach works well when you can list the labels you care about. After the catalog grows past what you can reasonably enumerate, writing a rule for each label becomes a maintenance burden and consumes rule capacity you’d rather spend elsewhere.

With dynamic label interpolation, you can reference labels by namespace instead of by individual name, so a single rule resolves to whichever labels matched during evaluation with no requirement to enumerate each one. You write a ${namespace:} clause in a header value or custom response body, and AWS WAF substitutes the matched values at evaluation time. The feature also gives you synthetic labels you can embed directly in responses, including the client IP address, request JA3 and JA4 fingerprints, and WAF request ID. The rest of this post explains how interpolation resolves labels by referencing four scenarios: forwarding classification data to your application, building custom block and challenge pages, redirecting traffic to a verification step, and segmenting Amazon CloudFront caches by bot category.

Interpolation syntax and behavior

Dynamic label interpolation uses a ${namespace:} syntax that resolves label values at evaluation time. You can use it in three places:

Where What it does Syntax
Custom request headers Inserts resolved label values into headers that AWS WAF forwards to your origin. For example, set X-Bot-Category to so your application receives the matched bot category directly. in the header value field
Custom response bodies Embeds label values and synthetic labels (such as client IP or request ID) in block pages, challenge pages, and other custom responses. in the response body Content field
Custom response headers Insert label values into response headers (for example, Location for redirects). in the response header Value field

In each case, AWS WAF reads the labels attached to the request and substitutes the resolved values into the string you provide.

The interpolation syntax

Include a ${namespace:} clause anywhere you would normally put a header value or custom response body. The trailing colon is what signals interpolation, telling AWS WAF to resolve every label in that namespace rather than match a single named label. AWS WAF evaluates each clause against the labels on the request and follows three rules:

  • Single match – The clause resolves to the label’s terminal value. If the request carries awswaf:managed:aws:bot-control:bot:category:scraping, then ${awswaf:managed:aws:bot-control:bot:category:} resolves to
    scraping.
  • Multiple matches – AWS WAF strips the namespace prefix and returns the values as a comma-separated list, such as scraping,advertising.
  • No match – The clause resolves to an empty string.

This is backward compatible. AWS WAF only interpolates a value when it contains a ${...} clause, so anything else passes through unchanged. There are no new API fields to set because the syntax is written directly into your existing string values. AWS WAF label namespaces are already colon-delimited (for example, awswaf:managed:aws:bot-control:bot:category:), meaning the required trailing colon won’t collide with header values that don’t follow that pattern.

Synthetic labels

Not every value you might want comes from a rule match. Synthetic labels are derived from the request itself, such as the client’s IP address, the AWS WAF request ID, or the TLS fingerprint, and you interpolate them with the same syntax.

Synthetic label Description
${awswaf:request_id:} The unique AWS WAF request identifier
${awswaf:ip:} The client IP address
${awswaf:ja3:} The JA3 TLS fingerprint
${awswaf:ja4:} The JA4 TLS fingerprint

Because synthetic labels work everywhere ${namespace:} interpolation does, you can mix them with namespace-based labels in a single value and pass both to your origin in whatever format suits your application.

The following examples use Bot Control labels, but interpolation isn’t limited to them. It works with most namespaces including labels from other AWS Managed Rules, such as account takeover prevention, account creation fraud prevention, and the IP reputation and anonymous IP lists, as well as labels from AWS Marketplace managed rule groups. This works with labels you custom define based on your own requirements in your own rules.

The same applies to custom labels you define in your own rules. Consider a configuration that classifies requests into tiers based on an API key header, where one rule applies the label and a second interpolates the namespace to forward the result. The first rule matches requests whose x-api-key header begins with pk_enterprise_ and applies the label app:tier:enterprise.

{
  "name": "classify-tier",
  "priority": 100,
  "statement": {
    "byte_match_statement": {
      "search_string": "pk_enterprise_",
      "field_to_match": {
        "single_header": {
          "name": "x-api-key"
        }
      },
      "positional_constraint": "STARTS_WITH",
      "text_transformations": [
        {
          "priority": 0,
          "type": "NONE"
        }
      ]
    }
  },
  "rule_labels": [
    {
      "name": "app:tier:enterprise"
    }
  ],
  "action": {
    "count": {}
  }
}

The second rule matches labels in the app:tier namespace and forwards the resolved value, enterprise, in the x-customer-tier header.

{
  "name": "forward-tier",
  "priority": 200,
  "statement": {
    "label_match_statement": {
      "scope": "NAMESPACE",
      "key": "app:tier:"
    }
  },
  "action": {
    "count": {
      "custom_request_handling": {
        "insert_headers": [
          {
            "name": "x-customer-tier",
            "value": "${awswaf:<ACCOUNT_ID>:webacl:<WEBACL_NAME>:app:tier:}"
          }
        ]
      }
    }
  }
}

In rule_labels, you use the short label name, app:tier:enterprise, and AWS WAF prefixes it with the web ACL context to produce the fully qualified label awswaf:ACCOUNT_ID:webacl:WEBACL_NAME:app:tier:enterprise. A label match statement accepts the short namespace (app:tier:) however an interpolation reference must use the fully qualified the account and web access control list (ACL) context. The payoff is that you can add app:tier:standard, app:tier:trial, or other tiers later, and the forwarding rule picks them up with no changes.

Interpolation also reaches namespaces that the static model never could. Values like the browser fingerprint (awswaf:managed:token:fingerprint) and the unique browser ID (awswaf:managed:token:id) change from request to request, so you can’t write a rule for each one. With interpolation you forward them as ${awswaf:managed:token:fingerprint:} and ${awswaf:managed:token:id:}, which means you can perform in real time device-level tracking, session correlation, and fraud detection that depend on these token-derived signals.

Application signaling

An application signaling pattern uses the labels and forwards them to the origin as customer request headers. After the headers arrive, your application can see how AWS WAF classified the request and decide what to do with that verdict.

Enumerating each label individually doesn’t scale. The common protection level of Bot Control alone tracks more than 650 self-identifying bots and agents, from crawlers to AI data collectors to monitoring services, and targeted protection adds behavioral and machine learning (ML) detection for bots that don’t announce themselves. Mapping only the known bot:category namespace to headers would take hundreds of rules, each one identical except for a hardcoded value. If you followed steps in the blog post How to use AWS WAF Bot Control for Targeted Bots signals and mitigate evasive bots with adaptive user experience, you’ve already mapped labels to confidence levels this way.

The following example forwards the advertising bot category as a header, one of the hundreds you would write to cover the namespace.

{
  "name": "add-header-for-bot-category-advertising",
  "statement": {
    "label_match_statement": {
      "scope": "LABEL",
      "key": "awswaf:managed:aws:bot-control:bot:category:advertising"
    }
  },
  "rule_action": {
    "count": {
      "custom_request_handling": {
        "insert_headers": [
          {
            "name": "bot-category",
            "value": "advertising"
          }
        ]
      }
    }
  }
}

Interpolation collapses that into a single rule. The scope changes from LABEL to NAMESPACE, and the value uses a ${...} clause instead of a hardcoded string. When a request matches, each header resolves to whatever the managed rule group actually applied, whether that is advertising, scraping, or a category that doesn’t exist yet.

{
  "name": "forward-waf-signals",
  "statement": {
    "label_match_statement": {
      "scope": "NAMESPACE",
      "key": "awswaf:managed:aws:bot-control:bot:category:"
    }
  },
  "rule_action": {
    "count": {
      "custom_request_handling": {
        "insert_headers": [
          {
            "name": "x-waf-bot-category",
            "value": "${awswaf:managed:aws:bot-control:bot:category:}"
          },
          {
            "name": "x-waf-bot-name",
            "value": "${awswaf:managed:aws:bot-control:bot:name:}"
          },
          {
            "name": "x-waf-bot-signals",
            "value": "${awswaf:managed:aws:bot-control:signal:}"
          },
          {
            "name": "x-waf-fingerprint",
            "value": "${awswaf:managed:token:fingerprint:}"
          },
          {
            "name": "x-waf-token-id",
            "value": "${awswaf:managed:token:id:}"
          },
          {
            "name": "x-waf-client-ip",
            "value": "${awswaf:ip:}"
          }
        ]
      }
    }
  }
}

This rule matches on the bot:category namespace, then forwards several related namespaces alongside it as separate headers. A more detailed analysis of The x-waf-bot-signals header shows multi-value resolution: the signal: namespace can hold several labels at one time, such as non_browser_user_agent and automated_browser, and they resolve to a comma-separated list. The x-waf-fingerprint and x-waf-token-id headers carry token-derived values unique to each device, which your origin can use for session correlation and fraud detection. And x-waf-client-ip uses a synthetic label to pass the client IP as AWS WAF sees it.

Using these headers, your application can make decisions that AWS WAF can’t make on its own. A signed-in customer flagged with a bot signal might get a simplified page or a different backend, whereas an anonymous session carrying the same signal is blocked outright. A request with several bot signals during a flash sale might be pushed down a queue rather than rejected. A load balancer or API gateway can read the headers and route to different origin pools, sending search_engine traffic, for instance, to a rendering service tuned for crawlers.

These headers are also available to Amazon CloudFront Functions so you can configure custom logic before the request ever reaches your origin.

AWS WAF supplies the signal, and your application supplies the judgment with AWS planning to keep extending this pattern with more detection signals at the edge and more ways to act on them in your application.

Custom block and challenge pages with debug information

False positives are an unavoidable cost of bot mitigation, and the harder problem is usually diagnosing them after they have occurred. Synthetic labels assist with this by embedding the client IP and the AWS WAF request ID in a custom response body, and you give blocked or challenged users a concrete reference to quote when they report a problem. The same approach works for a block page, a CAPTCHA challenge, or a silent challenge because each one supports interpolation in its response body.

{
  "CustomResponseBodies": {
    "BlockPage": {
      "Content": "Your request was blocked.\n\nIP: ${awswaf:ip:}\nRequestID: ${awswaf:request_id:}\n\nIfyou believe this is an error, contact support with the Request ID above.",
      "ContentType": "TEXT_PLAIN"
    }
  }
}

This helps your support workflow because a user who reports they’re blocked can give you the request ID from the page. You search the AWS WAF logs for that ID, look at the rules and labels that matched, and decide whether it was a false positive. There’s no requirement to go back to the user and ask them to reproduce the issue or guess when it happened. For applications where a wrongful block is costly, that shortcut between the user’s screen and your logs is worth building in.

Verification redirects with embedded context

Sometimes the right response isn’t a block but a detour sending suspicious traffic to a verification page before letting it continue. You can build this with AWS WAF by interpolating the client IP and request ID into the redirect target, which is shown in the following example.

{
  "Action": {
    "Block": {
      "CustomResponse": {
        "ResponseCode": 302,
        "ResponseHeaders": [
          {
            "Name": "Location",
            "Value": "/verify?ip=${awswaf:ip:}&rid=${awswaf:request_id:}"
          }
        ]
      }
    }
  }
}

The Location header resolves to an example such as /verify?ip=203.0.113.42&rid=a1b2c3d4-.... The verification endpoint can use the IP for a geo or rate-limit check and the request ID to align the visit with your AWS WAF logs, then send the user on when they pass. Because the redirect is constructed in AWS WAF, you get this behavior without touching the origin application.

CloudFront cache segmentation with AWS WAF labels

When AWS WAF is used in front of Amazon CloudFront, a header that a rule inserts is available to CloudFront when it computes the cache key, which means you can configure and segment your cache by classification. You can interpolate the bot category into a custom header to instruct CloudFront to include that header in the cache key and keep a separate cached response per category. The x-waf-bot-category header from the example forwarding rule above performs this action.

To put this into context, a search_engine request gets a pre-rendered, edge-cached version of the page built for crawling, and if there is a request with no bot label, this request gets the full dynamic page. A scraping request gets a minimal response, also from cache. Crawlers receive indexable content, scrapers stop consuming origin capacity, and human visitors notice no difference. After the first request in each category, all subsequent requests are served from the edge.

You can run the same approach at the origin instead for finer control over freshness. Configure your application to read the classification header and set Cache-Control accordingly and use no-store for unlabeled human traffic to provide fresh content, and longer TTLs for bot-targeted responses so they stay at the edge and off your origin. Which layer you choose depends on how much of this logic you want in CloudFront compared to your own code.

Conclusion

Dynamic label interpolation doesn’t change how labels work, it changes how much rule configuration you need to act on them. A namespace that used to take one rule per value now takes one rule total, and it keeps working as the Bot Control catalog grows past its current 650-plus entries. Along the way, you pick up request-specific block pages, redirects that carry their own context, and cache segmentation keyed on classification. None of these capabilities is dramatic on its own, but when you put them together, you can pair edge classification with judgment in your application.

The feature fits AWS WAF the same way you already use it, with no breaking changes, making adoption a matter of editing rule configurations rather than rebuilding anything. AWS will improve these features in the future by adding detection signals and interpolation capabilities. If you build something with this or would like to see a use case covered in a future post, let us know. You can contribute examples to the AWS Samples repository, start a discussion on AWS re:Post, or leave a comment.

To get started:

Using the URL of this post, you can enter the following examples as prompts in your coding assistant to use this new feature in your preferred environment.

  • “Using the patterns in the blog post, review my current AWS WAF configuration and identify which static label-to-header mappings can be replaced with dynamic interpolation rules.”
  • “Create a minimal WAF WebACL (CDK or AWS CloudFormation) with one rule that forwards Bot Control labels to the origin as request headers using `${namespace:}` syntax.”
  • “Using the AWS Sample referenced in this post, add a new rule that demonstrates dynamic label interpolation with a different managed rule group such as account takeover prevention.”
  • “My `${namespace:}` interpolation resolves to an empty string. Walk me through the debugging steps: verify the label namespace, check rule priority ordering, and confirm the fully qualified namespace for custom labels.”
  • “Design a CloudFront cache segmentation strategy using WAF dynamic label interpolation. Include the WAF rule and the origin-side Cache-Control header approach.”

If you have feedback about this post, submit comments in the Comments section below.


Eitav Arditti

Eitav is a Senior Solutions Architect at AWS and a technology leader with over 15 years of experience in the tech industry. He specializes in edge computing, serverless, and platform engineering, and works with engineering teams to design secure, globally scalable architectures on CloudFront and AWS WAF. His current focus is on internet-scale systems—from global content delivery to edge security.

Emil Hernvall

Emil Hernvall

Emil is a Principal Engineer at AWS on the AWS WAF team, focused on bot and DDoS detection. He works on the detection systems behind the AWS internet-scale protection against automated abuse and large-scale volumetric attacks.

Amitai Rottem

Amitai Rottem

Amitai is a Principal Product Manager at AWS on the AWS WAF team, focused on bot detection and threat intelligence. He brings over 20 years of experience in enterprise security across product management, software development, and startups, including prior roles at large technology companies.

Introducing the Amazon GuardDuty investigation agent: on-demand AI-powered threat assessment

20 July 2026 at 23:59

The new Amazon GuardDuty investigation agent (now in public preview) investigates security findings across your Amazon Web Services (AWS) environment, reducing investigation time from hours to minutes.

GuardDuty is our managed threat detection service that continuously monitors your AWS accounts and workloads for suspicious, potentially malicious activity, and unauthorized behavior, delivering detailed security findings for visibility and remediation.

Whether you’re investigating a single suspicious finding or assessing security posture across your entire organization, the investigation agent provides structured assessments providing risk levels, confidence scores, and actionable recommendations.

Security teams can spend hours investigating security findings and correlating data across multiple tools. The GuardDuty investigation agent automates this correlation, providing actionable intelligence, built directly into GuardDuty and accessible on demand through the AWS Management Console, AWS Command Line Interface (AWS CLI), AWS APIs, or AWS SDKs.

This post shows you how to:

  • Enable the investigation agent in your GuardDuty console.
  • Create your first investigation through the console or AWS CLI.
  • Use the investigation agent with the AWS MCP server for AI-assisted security operations

Key features of the GuardDuty investigation agent

The GuardDuty investigation agent provides APIs using the same patterns you already know from GuardDuty. Each completed investigation returns a risk level, confidence assessment, MITRE ATT&CK® technique mapping, resource mapping, and prioritized recommendations.

You can scope investigations from the console for a specific finding, an account, or all accounts across your organization. Alternatively, the AWS CLI and API accept a free-form trigger prompt of up to 2,048 characters, so you can describe what to investigate in natural language and guide the analysis of the agent by specifying areas of concern, suspected root causes, or priorities for the investigation.

The investigation agent APIs are also available through the official AWS MCP server, part of the Agent Toolkit for AWS, enabling integration into your existing security toolchains and AI-powered workflows. You don’t need to manage or interact with the agent directly. Call API endpoints, and the agent investigates findings, correlates evidence, and delivers an assessment without the overhead of managing complex configurations.

How the investigation agent analyzes findings

When you create an investigation, the agent uses cross-Region inference to process your findings based on scope and produces a structured output.

Cross-Region inference – GuardDuty investigation uses the Cross-Region Inference Service (CRIS), which selects the optimal AWS Region within your geography to process the investigation assessment. Your data remains stored only in the Region where the investigation request originates. However, investigation data and summary results might be processed outside that Region. Data is transmitted encrypted across the secure network provided by Amazon.

For more information about which inference Regions your request might be routed to see the Cross-Region inference routing table located in the investigation section of the Amazon GuardDuty User Guide.

Investigation output – Each completed investigation produces the following insights: Risk level (Info, Low, Medium, High, or Critical), Confidence (Unknown, Low, Medium, or High), Summary (description of findings and key observations), Investigation Details (additional context), and Recommended Actions (detailed actions including AWS CLI commands).

Account scoping – Account specification is required only when investigating a specific member account. For broader scopes such as your entire organization, no account ID is needed. The agent will only investigate findings within accounts you’re authorized to access per the authorization model that follows.

Prerequisites

Before you get started, make sure you have the following prerequisites in place:

  • Amazon GuardDuty enabled in your account
  • AWS account in a supported Region (see Availability section)

Required IAM permissions

You will need three new permissions: guardduty:CreateInvestigation to start new investigations, guardduty:GetInvestigation to retrieve results, and guardduty:ListInvestigations to view investigations for a given detector.

Example IAM policy:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "guardduty:CreateInvestigation",
        "guardduty:GetInvestigation",
        "guardduty:ListInvestigations"
      ],
      "Resource": "*"
    }
  ]
}

Authorization model

Administrator accounts can create investigations, retrieve results, and view investigation lists for themselves and their member accounts. Member accounts can only retrieve results and view investigation lists for their own account. Member accounts can’t create investigations and can’t access investigations belonging to other accounts or the administrator account. Account specification is required only when investigating a specific member account. For your own account or accounts across your organization, no account ID is needed.

To enable and create your first investigation

Before you begin, verify you have the required IAM permissions as described in the prerequisites .

  1. Open the AWS Management Console in the desired supported Region and navigate to Amazon GuardDuty.
  2. In the navigation pane, choose Investigations.
Figure 1: GuardDuty investigation dashboard

Figure 1: GuardDuty investigation dashboard

  1. If investigations aren’t enabled choose Go to Settings and then enable investigations by choosing Enable.
Figure 2: GuardDuty investigations enablement screen

Figure 2: GuardDuty investigations enablement screen

  1. After investigations are enabled, navigate back to the investigations page.
  2. In the navigation pane, choose Initiate Investigation.
Figure 3: GuardDuty initiate investigation

Figure 3: GuardDuty initiate investigation

  1. Select a scope for your investigation:
    • Enter a GuardDuty Finding ID: Use when you want to investigate a specific GuardDuty finding in depth
    • Enter an AWS Account ID: Use when you want to assess the overall security posture of a specific AWS account
    • All accounts: Use for organization-wide security assessment or when investigating potential lateral movement
    • Choose Initiate investigation.
Figure 4: GuardDuty investigation setup

Figure 4: GuardDuty investigation setup

  1. Wait for the investigation to complete (typically 2–5 minutes for account level and 10–12 minutes for specific finding investigations during preview). The status updates automatically.
  2. When the investigation completes, select the investigation title to view the full assessment.
Figure 5: GuardDuty investigation completed menu

Figure 5: GuardDuty investigation completed menu

The investigation assessment contains detailed information about the investigation including general information, a summary of the investigation, mapping, assessment of the threat, and recommended actions.

The General Information section displays the investigation ID, status, triggered-by account, and creation timestamp.

Figure 6: General information section of the assessment

Figure 6: General information section of the assessment

The summary section provides a narrative of key observations and findings.

Figure 7: Summary section of the assessment

Figure 7: Summary section of the assessment

The mapping section shows attack techniques and affected AWS resources.

Figure 8: MITRE ATT&CK mapping section of the assessment

Figure 8: MITRE ATT&CK mapping section of the assessment

The Threat Assessment section displays the risk level, confidence score, and detailed threat analysis.

Figure 9: Threat assessment section

Figure 9: Threat assessment section

The Recommended Actions section lists prioritized remediation steps.

Figure 10: Recommended actions section of the assessment

Figure 10: Recommended actions section of the assessment

Investigations can also be conducted with the AWS CLI or SDK using the following API endpoints:

  • CreateInvestigation – Initiates a GuardDuty investigation that automatically analyzes security findings, correlates related activity, performs account-level analysis, and produces a structured investigation summary with recommended next steps.
  • GetInvestigation – Retrieve the status and results of a specific investigation, including the assessment from the agent, correlated evidence, and recommended actions when completed.
  • ListInvestigations – View investigations across your environment with filtering and pagination.

To run investigations using the AWS CLI

Investigations are asynchronous because the agent queries multiple data sources, correlates findings across services, and performs AI-based analysis. After creating an investigation, you’ll need to check its status periodically until it completes.

Step 1: Find your detector ID

Each GuardDuty deployment has a unique detector ID per-account and per-Region that identifies your specific GuardDuty configuration. You will need this for all AWS CLI operations, especially if you have GuardDuty enabled in multiple Regions. You can find your detector ID in the GuardDuty console under Settings, or by running the following command and specifying the Region. For example, if the GuardDuty detector of interest were in the us-east-1 (N. Virginia) Region

aws guardduty list-detectors –-region=us-east-1

Expected response:

{
  "DetectorIds": [
    "12abc34d567e8fa901bc2d34eexample"
  ]
}

Note: the DetectorIDvalue from the response, you will use it in all subsequent commands.

Or if working only in the same Region, the session can be set as an environment variable to avoid repetition, for example on Linux:

export AWS_DEFAULT_REGION=us-east-1

See the AWS CLI documentation for guidance on configuring this for additional operating systems.

Step 2: Create an investigation

The following is an example of code to investigate a specific finding:

aws guardduty create-investigation us-east-1 \
--detector-id 12abc34d567e8fa901bc2d34eexample \
--trigger-prompt "Investigate this finding ID 1ab2c3d4e5f6a7b8c9d0e1f2a3b4c5d6"

The --trigger-prompt parameter is useful when you have context that isn’t captured in GuardDuty metadata or consumable through the API.

Expected response:

{
  "InvestigationId":"a1b2c3d4-5678-90ab-cdef-ef1234567890"
}

To investigate findings across an entire AWS account, use the following example:

aws guardduty create-investigation –-region=us-east-1 \
--detector-id 12abc34d567e8fa901bc2d34eexample \
--trigger-prompt “Investigate findings in Account 123456789012”

To investigate findings across an entire organization:

aws guardduty create-investigation –-region=us-east-1 \
--detector-id 12abc34d567e8fa901bc2d34eexample \
--trigger-prompt “Investigate findings across my AWS Organization”

Step 3: Check investigation status

Check the status of the investigation shown here using the AWS CLI query command to filter and list only the Status section of the output for simplicity:

aws guardduty get-investigation –-region=us-east-1 \
--detector-id 12abc34d567e8fa901bc2d34eexample \
--investigation-id a1b2c3d4-5678-90ab-cdef-ef1234567890 --query 'Investigation.Status'

Repeat this command until the Status field shows COMPLETED.

Example completed response output:

{
  "Investigation": {
    "InvestigationId": "a1b2c3d4-5678-90ab-cdef-ef1234567890",
    "Status": "COMPLETED",
    "TriggerPrompt": "Investigate finding 1ab2c3d4e5f6a7b8c9d0e1f2a3b4c5d6 in account 123456789012",
    "TriggeredBy": "123456789012",
    "RiskLevel": "Critical",
    "Risk": "Active multi-stage runtime compromise on EKS worker node with root-privileged reverse shell, Docker socket access, malicious file execution, and 500 multi-tactic runtime signals — behavioral evidence is consistent with a genuine intrusion.",
    "Confidence": "High",
    "Summary": "{\"keyObservations\":{\"title\":\"...\",\"narrative\":\"...\",\"observations\":[...]},\"countermeasures\":[...],\"threatAssessment\":{...}}",
    "Cloud": {
      "Provider": "AWS",
      "Region": "us-east-1",
      "Account": "123456789012"
    },
    "Metadata": {
      "Product": {
        "Name": "AmazonGuardDuty AI Analyst",
        "Feature": "Investigation"
      },
      "Version": "1.0.0"
    },
    "StartTime": 1705319400.0,
    "EndTime": 1705319700.0
  }
}
  • Status values – RUNNING, COMPLETED, FAILED
  • Timing – Investigation times can very. Checking status every 30 seconds should be sufficient to yield results.
  • If status shows FAILED – Review the error message in the response and verify your permissions match the authorization model requirements.

To list all investigations for a given detector run the following, the max-results command is optional but useful to filter the number of returned results.

aws guardduty list-investigations –-region=us-east-1 \
--detector-id 12abc34d567e8fa901bc2d34eexample \
--max-results=10

Beyond running investigations manually, the API-first design addresses a common customer pattern: sending GuardDuty findings to third-party tools. You can now add automated investigation to those existing pipelines, so your team receives enriched, prioritized intelligence rather than raw alerts.

Consider a customer that routes GuardDuty findings through Amazon EventBridge to their Security Information and Event Management (SIEM) platform, where analysts manually investigate each alert. With the investigation agent, an AWS Lambda function can be placed into the pipeline that calls CreateInvestigation with the finding ID, waits for completion, and forwards the enriched results (risk level, confidence score, MITRE ATT&CK mapping, and recommended actions) to their SIEM alongside the original finding. Critical findings route directly to the customer incident response queue for further analysis or automation. Low-risk findings with high confidence get auto-closed or batched for weekly review. The analyst’s time shifts from repetitive log correlation to validating assessments and acting on confirmed threats.

This pattern works with SIEMs, ticketing systems, or automation platforms that can be customized to use the API or EventBridge messaging. The investigation agent fits into the pipeline as a processing step, not a destination.

The agent is fine-tuned on investigating GuardDuty findings. It’s distinct from other AWS frontier agents such as the AWS Security Agent and AWS DevOps Agent. The scope of the investigation agent is focused to deliver specialized analysis of GuardDuty findings.

Integration with the AWS MCP server

The Model Context Protocol (MCP) is an open standard that allows AI assistants to securely connect to external data sources and tools. Because the AWS MCP server implements this standard for AWS services, you can use it to add GuardDuty investigations into AI-powered workflows using tools like Kiro, Anthropic’s Claude, or other MCP-compatible clients.

To configure the AWS MCP server

  1. Configure your MCP client to connect to the AWS MCP server.
  2. Use natural language to invoke investigations (for example,“Investigate the recent Unauthorized Access finding for account 123456789012″).
  3. Review the investigation results returned through your MCP client. These results can vary depending on the model or agent being used, configuration, and the non-deterministic nature of AI.

Integrate the results into your existing agent automation or take manual action based on the findings.

Additional usage examples

  • “Investigate the latest high-severity finding in my production account”
  • “Create an investigation for finding ID abc123 in account 987654321098 and summarize what happened”
  • “List investigations from the last 24 hours and flag those that need human review”

How the investigation agent relates to AWS Security Incident Response

At re:Invent 2024, AWS launched AWS Security Incident Response (AWS SIR), a managed service that you can use to quickly prepare for, respond to, and recover from security incidents. AWS SIR and the GuardDuty investigation agent address different stages of your security workflow. The GuardDuty investigation agent provides an on-demand assessment capability. When your team needs deeper context on a specific finding, an account security posture, or the overall security posture of your organization. You create an investigation and receive a structured assessment with risk levels, confidence scores, MITRE ATT&CK® technique mappings, and actionable recommendations. Security analysts can use this to quickly understand the scope and severity of what GuardDuty has detected.

When you create an AWS-supported case through AWS SIR, a SIR investigation agent activates, working in parallel with AWS Security Incident Response engineers to gather evidence and deliver an investigation summary within minutes. AWS SIR is purpose-built for active security events where you need both AI-powered automation and human expertise to coordinate containment and recovery.

Security teams can use these capabilities to assess and prioritize findings on demand using the GuardDuty investigation agent, escalate confirmed issues to stakeholders with supporting evidence, and create or update an AWS-supported case to accelerate involvement from the AWS SIR team when additional support is needed.

Availability and pricing

Public preview of the GuardDuty investigation agent is available in 10 AWS Regions including US East (N. Virginia), US East (Ohio), US West (Oregon), Canada (Central), Europe (Frankfurt), Europe (Ireland), Europe (London), Europe (Paris), Europe (Stockholm), and Asia Pacific (Tokyo).

During public preview, the investigation agent is available at no charge. Usage is limited to 10 investigations per account per day, with a cumulative limit of 100 investigations per account during the preview period. Failed investigations do not count toward these quotas.

Start investigating findings today

The Amazon GuardDuty investigation agent reduces investigation time from hours to minutes, letting your security team focus on confirmed security events rather than manual correlation.

Get started by:

  1. Enabling the investigation agent in your GuardDuty console
  2. Creating your first investigation using a recent GuardDuty finding
  3. Reviewing the structured assessment, including risk level and recommended next steps

For organizations using the AWS MCP server, you can also invoke investigations through natural language in your AI assistant of choice.

Learn more

If you have feedback about this post, submit comments in the Comments section below.


Allan Holmes

Allan Holmes

Allan brings over 20 years of experience spanning security & compliance, networking, and DevOps to his current role as a Security Specialist. Giving him a uniquely holistic view of cloud security challenges. Allan holds multiple technical certifications from AWS, ISC2, CompTIA, and an MBA, enabling him to bridge deep technical expertise with business strategy. Outside of work, Allan is an avid gardener and electronics enthusiast who enjoys exploring innovative technologies hands-on.

KAPE 101: A Kroll Artifact Parser and Extractor Cheatsheet

Spend time performing forensic analysis on the Windows Operating System and you'll see a host of artifacts that can be used to identify adversary activity. From changes to the registry to the System Resource Utilization Monitor, Windows artifacts run deep. The challenge is locating, extracting, and parsing these artifacts in an efficient manner.

The post KAPE 101: A Kroll Artifact Parser and Extractor Cheatsheet appeared first on Black Hills Information Security, Inc..

Authenticate legitimate AI agent traffic with AWS WAF Bot Control

14 July 2026 at 17:18

As AI agents and automated tools increasingly access web applications, distinguishing legitimate bot traffic from malicious attempts has become a critical security challenge. Traditional approaches such as IP-based filtering and reverse DNS lookups fail in multi-tenant systems (such as Amazon Bedrock AgentCore) where thousands of distinct workloads share the same IP space. Attackers can easily spoof user agents, and manual allowlists don’t scale with growing demand.

Web Bot Authentication (WBA), available in AWS WAF Bot Control since November 2025, solves this challenge by implementing cryptographic signatures that provide tamper-proof verification of bot identities. WBA uses asymmetric cryptography to verify that a request comes from an authorized automated agent, relying on two active Internet Engineering Task Force (IETF) drafts: a directory draft for sharing public keys, and a protocol draft defining how keys attach crawler identity to HTTP requests.

With WBA, you can confidently identify trusted automated access while maintaining granular control through WAF labels, creating a more secure and manageable ecosystem for both bot operators and website owners. AWS WAF Bot Control respects WBA verification status by default, automatically allowing verified AI agent traffic.

This post provides a deeper technical guide to implementing WBA with AWS WAF. You learn how WBA works, explore the new labels and capabilities it introduces, and walk through a step-by-step implementation—including signing code—to authenticate bot traffic using cryptographic signatures.

How Web Bot Authentication works with AWS WAF

WBA uses asymmetric cryptography to verify bot identities through HTTP message signatures. The process works as follows:

  1. Bot registration – Bot operators publish their public keys in a signature directory. AWS WAF regularly polls these directories and maintains a valid key registry.
  2. Request signing – Each bot operator’s request is signed using their private key following the IETF standard HTTP Message Signatures (RFC 9421).
  3. Verification – AWS WAF verifies signatures against known public keys associated with the bot operator and appends labels related to verification status.

A typical WBA-signed request includes headers like the following:

Signature-Agent: https://signature-agent.test
Signature-Input: sig2=("@authority" "signature-agent")
;created=1735689600
;keyid="poqkLGiymh_W0uP6PZFw-dvez3QJT5SolqXBCW38r0U"
;alg="ed25519"
;expires=1735693200
;nonce="e8N7S2MFd/qrd6T2R3tdfA..."
;tag="web-bot-auth"
Signature: sig2=:jdq0SqOwHdyHr9+r5jw3iYZH6aNGKijYp/EstF4RQ..

The following sequence diagram shows how AWS WAF verifies bot signatures and applies labels for allow or block decisions.

Figure 1 – AWS WAF Web Bot Authentication verification flow

Figure 1 – AWS WAF Web Bot Authentication verification flow

The workflow shown in figure 1 includes the following steps:

  1. A bot sends a signed request to Amazon CloudFront and is inspected by AWS WAF Bot Control
  2. AWS WAF Bot Control retrieves the bot operator’s public key from the signature directory
  3. AWS WAF Bot Control verifies the ed25519 signature
  4. AWS WAF Bot Control appends a verification label (verified, invalid, expired, or unknown_bot)

AWS WAF Bot Control evaluates rules using the label to allow or block the request.

New capabilities added to AWS WAF

With the addition of WBA, the following capabilities were added to AWS WAF.

Cryptographic bot verification

When a bot sends a request, it includes HTTP message signatures that AWS WAF validates at the edge using the AWS WAF Bot Control rule group (version 4.0 and later). This validation process adds minimal latency to requests while providing cryptographic certainty about the bot’s identity. HTTP Message Signatures is an open IETF standard (RFC 9421) that defines a mechanism for signing and verifying HTTP messages using asymmetric keys—in practice, this means a bot cryptographically signs specific headers and metadata of each request, and the receiver can verify the signature using the bot’s published public key.

New labels within AWS WAF for granular control

AWS WAF automatically validates signatures, and successfully validated traffic is immediately marked as verified. This verification status can be used in WAF rules and bot management policies, giving you the ability to write your own rules based on the new functionality.

The following table describes the new labels.

Label Meaning Suggested action
awswaf:managed:aws:bot-control:bot:web_bot_auth:verified Successful cryptographic verification Allow
awswaf:managed:aws:bot-control:bot:web_bot_auth:invalid Failed verification attempt Block or rate-limit
awswaf:managed:aws:bot-control:bot:web_bot_auth:expired Expired key used Block and alert
awswaf:managed:aws:bot-control:bot:web_bot_auth:unknown_bot Unrecognized key Monitor or block
awswaf:managed:aws:bot-control:bot:vendor:<vendor_name> Bot vendor or operator Use for vendor-specific rules
awswaf:managed:aws:bot-control:bot:name:<rfc_name> Bot name (RFC token from WBA) Use for bot-specific rules
awswaf:managed:aws:bot-control:bot:account:<hash> AWS account identifier (Amazon Bedrock AgentCore agents only) Use for account-level controls

AWS WAF now automatically allows verified AI agent traffic

AWS WAF Bot Control now respects WBA verification status by default, automatically allowing verified AI agent traffic. This includes two specific behavior changes:

  • Category:AI rule update – Previously, the Category:AI rule under common Bot Control blocked unverified bots. Bot Control now checks WBA verification status before applying this rule.
  • TGT_TokenAbsent rule update – The TGT_TokenAbsent rule, which detects requests without a WAF token, no longer matches requests that carry the web_bot_auth:verified label.

Key benefits for AWS WAF customers

WBA with AWS WAF delivers several advantages for organizations managing automated traffic at scale.

  • Enhanced bot visibility – Clear identification of distinct bots operating from multi-tenant platforms like Amazon Bedrock AgentCore, providing transparency into automated traffic sources. The AWS WAF console includes a new AI activity dashboard that provides a centralized view of AI bot and agent traffic across your protected resources.
  • Enhanced security – Cryptographic verification of bot identities using industry-standard signing mechanisms.
  • Reduced false positives – Accurate distinction between legitimate and malicious automated traffic, particularly in shared IP environments.
  • Industry alignment – Alignment with industry standards and major content delivery network (CDN) providers for consistent bot authentication across platforms.

Customer use cases for WBA with AWS WAF

Across industries, organizations use WBA to grant automated agents secure, controlled access to their web applications. The following scenarios highlight where this capability delivers real-world value:

  • Verified customer support agents – Authenticate AI-powered chat and support bots so websites can recognize them as approved, registered agents. This enables seamless customer service automation while maintaining security controls and audit trails.
  • Automated crawling and indexing – Allow search engine crawlers and content indexers to fetch pages with clear identity and scoped permissions. This reduces false-positive blocks, improves crawl efficiency, and helps legitimate bots access your content without triggering security controls.
  • Partner integrations – Third-party agents can access customer portals and APIs with explicit consent and granular, scoped access controls. This facilitates secure business-to-business (B2B) integrations while maintaining visibility into partner bot activity.
  • Enterprise automations and agents – Internal automation tools—including monitoring systems, QA bots, continuous integration and delivery (CI/CD) pipelines, and robotic process automation (RPA) solutions—get authenticated access to web applications with least-privilege access principles and full auditability.

Availability

WBA was introduced in Bot Control rule group Version_4.0 (November 2025) for Amazon CloudFront distributions, with continued support in later versions. With Version_6.0, WBA is available for resource types supported by AWS WAF across standard commercial AWS Regions.

Getting started: Developers or agents quick start

Whether you’re implementing WBA yourself or working with an AI coding assistant, the following steps walk you through deploying WBA, signing requests, and writing custom rules.

Step 1: Deploy the WBA-enabled Bot Control

Add the AWS WAF Bot Control rule group to your CloudFront-associated web ACL using static Version_4.0 or Version_5.0—both include WBA support for cryptographic bot verification. Version_5.0 (released February 2026) covers more than 650 unique bots and agents spanning categories including AI search engine crawlers, AI data collectors, AI assistants, and large language model (LLM) training crawlers.

Important: You must explicitly select one of these static versions.

The following example CloudFormation YAML snippet shows a bot control rule set configuration:

# Bot Control rule group with WBA support
ManagedRuleGroupStatement:
  VendorName: AWS
  Name: AWSManagedRulesBotControlRuleSet
  # Use Version_4.0 or higher for WBA support
  Version: Version_5.0
  ManagedRuleGroupConfigs:
    - AWSManagedRulesBotControlRuleSet:
        # COMMON level provides WBA verification
        # TARGETED level adds additional bot-specific protections
        InspectionLevel: COMMON

Step 2: Sign requests from your bot

If your agent runs on Amazon Bedrock AgentCore Browser, request signing is handled automatically—no additional configuration is required.

For agents running outside of AgentCore, registration APIs are on the roadmap that you can use to sign requests independently by:

  1. Generating an ed25519 key pair
  2. Hosting your public key in a signature directory
  3. Signing outbound HTTP requests using the Signature-Input and Signature headers with the web-bot-auth tag. For language-specific signing implementations, see the HTTP Message Signatures RFC (RFC 9421) and the AWS WAF Bot Control documentation.

Step 3: Write custom rules using WBA labels

Use the verification labels in custom WAF rules for granular traffic control, for example:

  • Allow – awswaf:managed:aws:bot-control:bot:web_bot_auth:verified
  • Rate-limit – awswaf:managed:aws:bot-control:bot:web_bot_auth:invalid
  • Alert on – awswaf:managed:aws:bot-control:bot:web_bot_auth:expired

Step 4: Monitor WBA traffic

Use AWS WAF metrics and logs to monitor authenticated bot traffic:

  • Review Amazon CloudWatch metrics for Bot Control rule group matches and set up alarms for anomalous or unexpected spikes in invalid or expired verification attempts.
  • Analyze AWS WAF logs to identify patterns in bot authentication attempts and filter on web_bot_auth labels.
  • Use the AI Activity Dashboard in the AWS WAF console for a centralized view of AI bot traffic. Visualize traffic trends, identify top bots and frequently targeted paths, and filter by verification status to decide which bots to allow, rate-limit, or block.

Conclusion

WBA with AWS WAF provides a cryptographically secure, standards-based approach to authenticating legitimate AI agent traffic. By moving from IP-based allowlisting to signature-based verification, you gain accurate bot identification that works across multi-tenant environments.

Looking ahead, our focus is to simplify bot authentication and make it safer by default. Registration APIs that agent owners can use to cryptographically verify bot identity and intent are on the roadmap, helping website owners quickly distinguish trusted automation from unknown traffic.

If you own an agent, adopt WBA and register your agent to receive verified status. In parallel, AWS continues to actively participate in the IETF web-bot-auth working group, advocating for complementary approaches—using both identifying and anonymous verification protocols—and will incorporate these standards into products as they mature to help your deployments stay aligned with the broader ecosystem.

To get started, see the AWS WAF Bot Control documentation and the HTTP Message Signatures RFC (RFC 9421).

If you have feedback about this post, submit comments in the Comments section below.


Harith Gaddamanugu

Harith Shantan Gaddamanugu

Harith is a Sr Edge Specialist Solutions Architect at AWS, where he architects critical infrastructure and security solutions that serve millions of users globally. With a decade of expertise in cloud perimeter protection and web acceleration, he guides large enterprises building resilient architectures. Outside work, Harith enjoys hiking and landscape photography with his family.

Author

Kaustubh Phatak

Kaustubh is a product leader specializing in AI/ML systems and enterprise security solutions. He has led cross-functional teams in deploying AI-powered products at scale, working closely with security architects and CISOs to address the intersection of AI innovation and cybersecurity risk. His work focuses on translating complex technical capabilities into business value, particularly in emerging technology domains where traditional frameworks don’t apply.

Secure Amazon container workloads using container attribute-based rules in AWS Network Firewall

1 July 2026 at 21:40

Today, you can use AWS Network Firewall to protect traffic flowing to and from containerized applications on Amazon Elastic Kubernetes Service (Amazon EKS) and Amazon Elastic Container Service (Amazon ECS) clusters. If you run AI and machine learning (ML) workloads on Amazon EKS—such as model inference, RAG pipelines, or JupyterHub—your containerized workloads require the same firewall protections you enforce for traditional applications. However, traditional firewall rules rely on IP addresses, and pod IPs in Kubernetes change frequently as containers scale or restart. Writing and maintaining static firewall rules based on these ephemeral IPs, CIDRs, and subnets is difficult and error-prone, which can leave gaps in your security posture.

Kubernetes Network Policies offer basic traffic control at the namespace level, operating at layers 3 and 4. Depending on your security requirements, you might need additional capabilities beyond what network policies provide: Layer 7 inspection, FQDN-based filtering, and protection from threats detected by managed IDS/IPS rules. Visibility into which pod or service generates blocked traffic is equally important, so you can troubleshoot faster and meet audit requirements.

You can use container attribute-based rules for Network Firewall to define firewall rules for your containerized workloads on both Amazon EKS and Amazon ECS using native container attributes, rather than relying on ephemeral IP addresses. For Amazon EKS, these attributes include namespaces, pod names, cluster names, and labels. This reduces the need to maintain IP-based rules in dynamic container environments. While this capability supports both Amazon EKS and Amazon ECS, this post focuses on Amazon EKS. Your containerized workloads get the same Network Firewall capabilities you use today.

There is no additional charge for the feature itself, because it’s included in the base tier of Network Firewall.

How it works

When you create a container association and link it to your EKS cluster, Network Firewall automatically discovers and tracks the pods that match your defined attributes (namespace, labels, cluster name) and resolves them to their current IP addresses. As pods scale up or restart, the firewall dynamically updates the IP-to-attribute mapping in near real-time and no manual rule updates are required. This approach keeps your firewall rules accurate in dynamic environments while minimizing performance impact on the EKS cluster. In multi-cluster environments, this feature enables centralized cross-cluster traffic inspection for any traffic that passes through the firewall.

Container attribute-based rules also enrich firewall alert logs with container context. Alert logs now include a new metadata field with the container association name associated with the matched rule. This gives security teams the ability to trace blocked, allowed, or alerted traffic directly back to the originating workload. Network Firewall exports these enriched logs to Amazon CloudWatch Logs and Amazon Simple Storage Service (Amazon S3), from where you can forward them to the SIEM of your choice. To bind these attribute groups to running workloads, Network Firewall continuously watches your EKS cluster for pod lifecycle events (create and delete) across the namespaces covered by your container association definition. This definition is stored in a container association, keyed by attribute name and value.

When published, you reference these @ aliases in stateful Suricata rules. The following are some common patterns:

  • Pod group rules: Allow only payment-service pods to reach the external payment gateway over TLS:
    pass tls @ecommerce_pods any -> any 443 (msg:"allow ecommerce to payment gateway"; tls.sni; content:“checkip.amazonaws.com”; flow:to_server,established; sid:1; rev:1;)
  • Layer 7 application rules : Enforce block from all pods from reaching malicious destinations:
    drop tls @all-pods any -> $EXTERNAL_NET any (msg:"Block malicious sites"; aws_domain_category:malicious-sites; sid:10; rev:1;)

At packet evaluation time, Network Firewall expands each @ reference against the current catalog. When pods scale, restart, or move between nodes, the controller refreshes group membership, and the firewall picks up the new IPs, hence no rule edits or operator intervention is required. Each match—whether alert, pass, or drop—streams to the logging destination of your choice with container context. This gives your team a real-time, auditable view of policy effectiveness and a feedback loop for tuning rules and pod-group definitions over time.

Getting started

The Network Firewall container attribute-based rules for Amazon container workloads can be configured using the AWS Management Console for Amazon Virtual Private Cloud (Amazon VPC), AWS Command Line Interface (AWS CLI), or AWS SDK by creating a container association. This container association then can be used to create attribute-based Network Firewall rules.

Prerequisites

This walkthrough requires an existing Network Firewall configured to filter traffic through your Amazon VPC. If you haven’t set one up yet, see Getting started with AWS Network Firewall.

Step 1 – Create a container association:

  1. In the AWS VPC console, navigate to Network Firewall, select Container associations. Choose Create container association.
  2. Enter a Name and optional Description for this container association.
  3. Under Cluster configuration, select the Cluster type and select your EKS cluster from the Cluster drop down.
  4. For Attribute filters, configure the EKS attribute to identify which pods to associate:
    • Attribute key: Enter the attribute key defined in your EKS cluster (for example, namespace, pod, cluster, or custom label key).
    • Attribute value: Enter an attribute key value defined in your EKS cluster.
Figure 1: Create container association

Figure 1: Create container association

Step 2 – Create an attribute-based firewall rule:

  1. In the AWS VPC console, navigate to Network Firewall, then select Network Firewall rule groups.
  2. Select Create rule group.
  3. For Rule group type, select Stateful rule group.
  4. For Rule group format, select Suricata compatible rule string.
    Figure 2: Rule group selection

    Figure 2: Rule group selection

  5. For Rule evaluation order, select Strict order. Choose Next.
  6. Under Describe rule group, enter a Name, Description, and Capacity for the rule group. Choose Next.
    Figure 3: Describe rule group

    Figure 3: Describe rule group

  7. Under IP set references, enter a variable name and from the resource ID drop-down, select the container association created in step 1.
  8. Under Suricata compatible rule string, enter your Suricata rule string. The following is a sample string used for this post:
    pass tls @ecommerce_pods any -> any any (msg:"allow ecommerce to payment gateway"; flow:to_server; tls.sni; dotprefix; content:".checkip.amazonaws.com"; endswith; nocase; alert; sid:101; rev:1;)
    
    reject tls @ecommerce_pods any -> any 443 (msg:"block ecommerce pods to external ecommerce website"; flow:to_server; tls.sni; dotprefix; content:".amazon.com"; endswith; nocase; alert; sid:104; rev:1;)

    Figure 4: Configure rules

    Figure 4: Configure rules

  9. Choose Next.
  10. Enter the details if required on the next options. For this post, we’re using the default values.
  11. On the review and create page, choose Create rule group.

Tests and results

To verify these rules are working as expected, test using the curl command on a pod in the ecommerce namespace. A curl request to www.amazon.comshould fail, because action=rejectis defined in the Suricata rule string. Similarly, a request to the payment gateway URL should succeed, because action=passis defined in the Suricata rule string.

Test 1 – Allowed traffic:

kubectl exec -n ecommerce deployment/payment-service -- curl -sk --max-time 5 -w "\nHTTP_CODE:%{http_code}\n" https://checkip.amazonaws.com/

HTTP_CODE:200

Test 2 – Blocked traffic:

kubectl exec -n ecommerce deployment/payment-service -- curl -sk --max-time 5 https://www.amazon.com 2>&1

curl: (35) Recv failure: Connection reset by peer
command terminated with exit code 35

Container association can also be used in a Standard stateful rules format.

Considerations

There are several important considerations when adopting this feature.

  1. Source NAT (SNAT) must be disabled so that the Network Firewall can see pod IP addresses. If SNAT remains enabled, only the node IP will be visible, preventing granular pod-level egress controls.
  2. This feature can’t enforce security on pod-to-pod traffic within the same node, because that traffic doesn’t traverse the Network Firewall endpoint. A separate solution is needed for this use case.
  3. Performance impact can vary based on rule complexity and traffic volume.

Conclusion

In this post, you learned how container attribute-based rules for AWS Network Firewall solve the challenge of securing dynamic containerized workloads. You explored how the feature maps Kubernetes attributes such as namespaces, pod names, cluster names, and labels to firewall rules, eliminating the need to track ephemeral IP addresses. You walked through how to create a container association to link your EKS cluster attributes to Network Firewall, and then how to reference that association using IP set references in Suricata compatible rule strings. This gives you granular traffic control of your Amazon EKS workloads with the same Network Firewall capabilities as traditional applications including layer 7 inspection, FQDN filtering, TLS decryption, and managed IDS/IPS rules along with enriched logging that traces traffic back to the originating workload.

If you have feedback about this post, submit comments in the Comments section below.


Amit Gaur

Amit Gaur

Amit, a Cloud Infrastructure Architect at AWS, brings his passion for technology and knowledge-sharing to the networking community. Specializing in network architecture design, he helps customers build highly scalable and resilient environments on AWS. Through technical guidance and architectural expertise, Amit enables customers to accelerate their cloud adoption journey while making sure their systems are built for scale and reliability.

Preetkumar Shah

Preetkumar Shah

Preetkumar is a Technical Account Manager at AWS, based in Atlanta, GA. He specializes in helping customers design and operate secure, scalable network architectures in the cloud. At AWS, he works with SMB customers and collaborates closely with service teams to proactively resolve complex challenges and ensure customers get the most from their AWS environment. Outside of work, his interests include spending time with family and going on trails.

Akash Kuman Sinha

Akash Kumar Sinha

Akash is a DevOps Consultant and GenAI Ambassador at AWS, where he helps customers transform their cloud operations through containerization and modern delivery practices. He specializes in container orchestration and DevOps automation, and is a regular speaker at AWS events across Europe. Outside of work, Akash is passionate about knowledge-sharing and exploring the intersection of generative AI and cloud-native innovation.

Amish Shah

Amish is a seasoned product leader with over 15 years of experience in developing innovative and scalable solutions for networking, security, and cloud use cases. He currently leads the AWS Network Firewall service, where he helps to develop security solutions that protect AWS workloads. Outside of work, Amish enjoys playing cricket and soccer, loves to travel, and has recently started collecting niche fragrances.

How to use the AWS Workload Credentials Provider for cross-account secret retrieval and prefetching secrets

1 July 2026 at 17:56

If you manage secrets across multiple AWS accounts or need faster secret access for latency-sensitive applications, this post shows you how to meet those requirements using two new features of the AWS Workload Credentials Provider (provider). You will learn how to configure role chaining for cross-account secret retrieval and prefetching of secrets to reduce cold-start latency.

By using role chaining, you can access secrets across AWS accounts through a single provider instance by assuming AWS Identity and Access Management (IAM) roles. Prefetching populates the provider’s in-memory cache with secrets at startup so your application can retrieve secrets without waiting for the first request to trigger a network call at runtime.

What is the AWS Workload Credentials Provider?

AWS Secrets Manager stores and rotates credentials, API keys, and other secrets. The AWS Workload Credentials Provider is a client-side HTTP service that retrieves and caches secrets locally. This reduces latency, improves availability during transient failures, and lowers costs. It supports post-quantum TLS by default, requires no language-specific SDK, and works across Amazon Elastic Compute Cloud (Amazon EC2), Amazon Elastic Container Service (Amazon ECS), Amazon Elastic Kubernetes Service (Amazon EKS), and AWS Lambda. For more details, see the Workload Credentials Provider documentation and GitHub repository.

Security considerations

The Server-Side Requst Forger (SSRF) token prevents unauthorized processes from accessing the provider’s HTTP endpoint. Only applications that can read the token file can retrieve secrets through the provider.

Any identity that can access the provider’s endpoint and SSRF token can retrieve secrets through role chaining. This means users with compute environment access can retrieve cross-account secrets when role assumption is configured. Scope the target role’s permissions to only the secrets required by following the principle of least privilege.

For prefetching, secrets are loaded into the provider’s in-memory cache at startup. Any process that can reach the provider’s localhost endpoint and provide a valid SSRF token can retrieve prefetched secrets from the cache.

Cross-account secret retrieval with role chaining

Organizations might store secrets in a dedicated AWS account, or need to share one secret across applications in different accounts. Until now, cross-account retrieval through the provider required attaching resource-based policies directly to each secret. Some customers prefer IAM role assumption. Before this feature, you had to deploy multiple provider instances with different credentials or build custom credential-switching logic. The provider now supports both approaches: resource-based policies and IAM role assumption. While role assumption is especially useful for cross-account scenarios, it also helps within the same account when secrets are protected by different customer-managed KMS keys.

When you include the roleArn query parameter in a request, the provider uses AWS Security Token Service (AWS STS) AssumeRole to obtain temporary credentials for the specified role and retrieves the secret with those credentials. The provider creates and caches a separate client for each role ARN, so subsequent requests to the same role reuse the existing client. Each role client maintains its own independent cache.

Note: The source account runs the Workload Credentials Provider and your application. The target account contains the secret you want to retrieve. A single provider instance in the source account can assume roles in one or more target accounts.

Prerequisites

  • A Workload Credentials Provider built and installed in your environment (see the README for build instructions)
  • AWS credentials configured in your compute environment with permission to call sts:AssumeRole on the target role ARN
    • If you also retrieve secrets from the source account through the provider, the credentials need secretsmanager:GetSecretValue and secretsmanager:DescribeSecret permissions for those secrets
  • A secret in a target AWS account that you want to retrieve
  • An IAM role in the target account with a trust policy that allows the provider’s identity to assume it

To build the Workload Credentials Provider

The provider is written in Rust and compiles to a single executable. The following steps are for an RPM-based system such as Amazon Linux 2023:

  1. Install build dependencies:
    sudo yum -y groupinstall "Development Tools"
  2. Install Rust:
    curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
    source "$HOME/.cargo/env"
  3. Clone the repository and build the provider (use the latest tag available):
    git clone --branch <git tag> https://github.com/aws/aws-workload-credentials-provider.git
    cd aws-workload-credentials-provider
    cargo build --release

The compiled binary is at target/release/aws-workload-credentials-provider.

To install the Workload Credentials Provider on Amazon EC2

After building the provider, install it as a system service on your EC2 instance and configure access to the SSRF token.

  1. After configuring your config.toml file (see Configuration options section), run the install script to deploy the provider as a systemd service and generate the SSRF token:
    cd aws_workload_credentials_provider_common/configuration
    sudo ./install --config config.toml
  2. Add your application user to the aws-wcp-token group. This grants your application permission to read the SSRF token file, which is required for all secret retrieval requests:
    sudo usermod -aG aws-wcp-token <APP_USER>

To install on Amazon ECS, Amazon EKS, or Lambda, see the installation instructions in the GitHub repository.

To verify the installation

  1. Check that the provider is running:
    curl -v -H \
        "X-Aws-Parameters-Secrets-Token: $(</var/run/awssmatoken)" \
        'http://localhost:2773/secretsmanager/get?secretId=<YOUR_SECRET_ID>'
  2. You’ll receive a JSON response with the secret value. If you see a connection refused error, check that the provider process is running. If you see a 401 or 403 error, verify the SSRF token file is readable and that the provider’s IAM credentials have secretsmanager:GetSecretValue and secretsmanager:DescribeSecret permissions.

Required permissions

The provider’s base IAM identity requires:

  • sts:AssumeRole on the target role ARN

The target role requires:

  • secretsmanager:GetSecretValue
  • secretsmanager:DescribeSecret

To configure the target account IAM role

Create an IAM role in the target account with a trust policy that allows the provider’s identity in the source account to assume it. Then attach a policy that grants access to the required secrets.

  1. Create an IAM role in the target account with a trust policy that allows the provider’s identity in the source account to assume it.
    {
        "Version": "2012-10-17",
        "Statement": [
            {
                "Effect": "Allow",
                "Principal": {
                    "AWS": "arn:aws:iam::111111111111:role/WCProviderRole"
                },
                "Action": "sts:AssumeRole"
            }
        ]
    }
    
  2. Attach a policy to this role that grants access to the secret:
{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "secretsmanager:GetSecretValue",
                "secretsmanager:DescribeSecret"
            ],
            "Resource": "arn:aws:secretsmanager:us-east-1:222222222222:secret:MyDatabaseSecret"
        }
    ]
}

To configure the source account IAM role

Before the provider can assume the role you created in the target account, grant it permission to call sts:AssumeRole. Attach the following policy to the provider’s IAM role in the source account:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": "sts:AssumeRole",
            "Resource": "arn:aws:iam::222222222222:role/CrossAccountSecretAccessRole"
        }
    ]
}

To retrieve the cross-account secret

Call the Workload Credentials Provider endpoint with the roleArn parameter. The following curl example shows how to retrieve a secret using a different IAM role:

curl -v -H "X-Aws-Parameters-Secrets-Token: $(</var/run/awssmatoken)" 'http://localhost:2773/secretsmanager/get?secretId=MyDatabaseSecret&roleArn=arn:aws:iam::222222222222:role/CrossAccountSecretAccessRole'

The following Python example shows the same operation:

import requests

def get_secret_cross_account():
    role_arn = "arn:aws:iam::222222222222:role/CrossAccountSecretAccessRole"
    url = f"http://localhost:2773/secretsmanager/get?secretId=MyDatabaseSecret&roleArn={role_arn}"

    with open('/var/run/awssmatoken') as fp:
        token = fp.read()

    headers = {
        "X-Aws-Parameters-Secrets-Token": token.strip()
    }

    response = requests.get(url, headers=headers)

    if response.status_code == 200:
        return response.text
    else:
        raise Exception(f"Status code {response.status_code} - {response.text}")

You can configure the maximum number of simultaneous assumed roles with the max_roles option in the provider’s TOML configuration file. The default is 20, and the range is 1–20.

Prefetching secrets at startup

By default, the Workload Credentials Provider populates its cache lazily—the first request for a secret triggers a network call to Secrets Manager. Prefetching reduces this cold-start latency by loading secrets at startup.

How prefetching works

You can configure prefetching by adding a [capabilities.secrets_manager.prefetch] section to the provider’s TOML configuration file. You can specify secrets to prefetch in two ways:

  • Explicit secrets – List specific secret IDs or ARNs using [[capabilities.secrets_manager.prefetch.secrets]] entries.
  • Tag-based discovery – Discover secrets by tag key using [[capabilities.secrets_manager.prefetch.filter_tags]] entries. The provider calls BatchGetSecretValue with tag key filters to find and cache all matching secrets.

You can use both methods together. Each entry optionally accepts a role_arn field for cross-account prefetching through role chaining.

Required permissions

The following permissions are required on the IAM role that performs the prefetch, depending on whether the secrets are in the source account or a target account.

  • secretsmanager:BatchGetSecretValue – Required on the source account role for source-account secrets, or on the target role for cross-account secrets
  • secretsmanager:ListSecrets – Required when using tag-based discovery (filter_tags), on whichever role is performing the discovery

Configuration options

You can tune prefetch behavior with the following options in the [capabilities.secrets_manager.prefetch] section of your TOML configuration file:

  • cache_buffer_ratio – The maximum fraction of the cache to fill per caching client during prefetch, in the range 0.1–1.0. The default is 0.8. For example, if your cache holds 100 secrets, a ratio of 0.8 prefetches up to 80, leaving room for 20 on-demand secrets to be cached.
  • max_jitter_seconds – The maximum random delay in seconds before starting the prefetch task, in the range 0–10. The default is 0 (no jitter). Use this to prevent fleet-wide synchronized API calls when deploying across many instances.

Example: Prefetch with explicit secrets

The following configuration prefetches two secrets at startup, one from the source account and one from a different account using role chaining:

[capabilities.secrets_manager.prefetch]
secrets = [
    { secret_id = "arn:aws:secretsmanager:us-east-1:111111111111:secret:MySecret-AbCdEf" },
    { secret_id = "cross-account-secret", role_arn = "arn:aws:iam::222222222222:role/CrossAccountSecretAccessRole" }
]

Example: Prefetch with tag-based discovery

The following configuration discovers and caches all secrets tagged with the Environment key, and all secrets tagged with the Team key in a different account:

[capabilities.secrets_manager.prefetch]
filter_tags = [
    { key = "Environment" },
    { key = "Team", role_arn = "arn:aws:iam::222222222222:role/CrossAccountSecretAccessRole" },
]

Example: Full configuration

The following example shows a complete provider configuration that combines both features:

[logging]
log_level = "info"

[capabilities.secrets_manager]
http_port = 2773
region = "us-east-1"

[capabilities.secrets_manager.cache]
ttl_seconds = 300

[capabilities.secrets_manager.prefetch]
cache_buffer_ratio = 0.6
max_jitter_seconds = 5
secrets = [
    { secret_id = "arn:aws:secretsmanager:us-east-1:111111111111:secret:MySecret-AbCdEf" },
    { secret_id = "arn:aws:secretsmanager:us-east-1:222222222222:secret:CrossAccount-AbCdEf", role_arn = "arn:aws:iam::222222222222:role/CrossAccountSecretAccessRole" },
]
filter_tags = [
    { key = "Environment" },
    { key = "Team", role_arn = "arn:aws:iam::222222222222:role/CrossAccountSecretAccessRole" },
]

Start the provider with your configuration file:

./aws-workload-credentials-provider sm start --config config.toml

Conclusion

This post showed you how to use role chaining for cross-account secret retrieval and prefetching to reduce cold-start latency. Role chaining simplifies multi-account architectures—a single provider instance can retrieve secrets across accounts using IAM role assumption. Prefetching reduces cold-start latency by populating the provider’s cache before your application makes its first request. Combined, these features let you run the Workload Credentials Provider across multiple accounts with faster secret access.

Further reading

Submit feedback in the comments below, or contact AWS Support with questions.


Derik Wang

Derik Wang

Derik is a Software Engineer on the AWS Secrets Manager team.

Paras Dhawan

Paras Dhawan

Paras is a Software Development Manager for AWS Secrets Manager, based in Seattle. Paras joined AWS in 2017 and has spent his career across AWS Identity, AWS Cryptography, and Credentials Distribution Systems. He is passionate to innovate, solve and simplify customer problems related to security, access, authorization and beyond.

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