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Claude Fable 5 and Mythos 5 “abruptly disabled” after US gov. ban

15 June 2026 at 16:32

Anthropic has been ordered by the US government to cut off its newest Claude Fable 5 and Mythos 5 models for fear of abuse by adversaries.

Reuters reports that Anthropic said it will “abruptly ​disable” its most advanced AI models for all users after the US government ordered it to suspend access to the models for foreign nationals, citing national security ‌concerns.

Officials reportedly believe a jailbreak could turn Fable 5 and Mythos 5 into vulnerability-discovery tools for adversaries, so Anthropic says it is disabling them worldwide rather than try to nationality‑filter access, since it is virtually impossible to verify every user’s nationality.

In a statement on its website, Anthropic says:

“The letter did not provide specific details of its national security concern. Our understanding is that the government believes it has become aware of a method of bypassing, or “jailbreaking” Fable 5. We reviewed a demonstration of this specific technique being used to identify a small number of previously known, minor vulnerabilities. These vulnerabilities all appear relatively simple, and we have found that other publicly-available models are able to discover them as well without requiring a bypass.”

Mythos 5 is the non-public full version, which is currently used only by government agencies and selected corporate partners to harden their systems. Fable 5 is a Mythos-class model that should supposedly be safe for general use.

It makes sense to me that if Fable 5 is easy to jailbreak, that it should fall under the same restrictions as Mythos 5. However, Anthropic maintains that it has built-in safeguards that mean queries on some topics will instead receive a response from the next-most-capable model, Claude Opus 4.8. 

The relationship between the US government and Anthropic had shown signs of easing in parts of the US government after tensions over military use, surveillance, and autonomous weapons. In March, defense Secretary Pete Hegseth designated the San Francisco-based company a “supply-chain risk to national security.”

To understand the nature of the argument, it is necessary to understand that Mythos 5 is described in multiple reports as particularly effective at identifying software vulnerabilities, including long‑standing bugs in complex, legacy systems such as those in banking and other critical infrastructure. Many view this as dual‑use: great for defense hardening, but catastrophic in the wrong hands.

In recent updates from major software vendors like Microsoft and Google, we’ve seen a growth in numbers of patched vulnerabilities after the vendors began using AI-guided search for new vulnerabilities in their own software. We also know that Mozilla found over 270 Firefox vulnerabilities with the aid of Anthropic’s new Claude Mythos model. 

What this means

In the wrong hands these vulnerabilities could definitely do a lot of harm. So, it looks like it will take some time before regular consumers and developers will gain access to Fable 5 and Mythos 5 entirely. However, existing Anthropic models (older Claude variants) remain available.

For home users who were simply chatting with Claude or using it to help with basic scripting, the change will mostly show up as “this specific version is unavailable” rather than a broader AI blackout.

Removing a high‑end vulnerability‑finding model from broad circulation increases the effort required for less‑resourced cybercriminals to automate discovery of complex bugs in consumer‑facing software and services only by so much. There are other models available on the black market that might be just as effective. And for most cybercriminals, turning a vulnerability into a method they can utilize in an exploit is much more relevant.


We don’t just report on threats—we remove them

Cybersecurity risks should never spread beyond a headline. Keep threats off your devices by downloading Malwarebytes today.

Microsoft’s biggest-ever Patch Tuesday fixes 206 bugs, including 3 zero-days

10 June 2026 at 14:43

This month’s Patch Tuesday fixes 206 security flaws in Microsoft software, making it the biggest Patch Tuesday release ever.

The update includes 32 critical vulnerabilities, as well as three publicly disclosed zero-days. Microsoft classifies these as zero-days because information about the vulnerabilities became public before patches were available. None are known to have been actively exploited by attackers.

The huge number of fixed vulnerabilities makes this the largest Patch Tuesday since Microsoft launched the program in October 2003. The company introduced the monthly update schedule after the Blaster worm caused disruption in the early days of Windows.

How to apply patches and check if you’re protected

These updates fix security problems and keep your Windows PC protected. Here’s how to make sure you’re up to date:

1. Open Settings

  • Click the Start button (the Windows logo at the bottom left of your screen).
  • Click on Settings (it looks like a little gear).

2. Go to Windows Update

  • In the Settings window, select Windows Update (usually at the bottom of the menu on the left).

3. Check for updates

  • Click the button that says Check for updates.
  • Windows will search for the latest Patch Tuesday updates.
  • If you have selected to get the latest updates as soon as they’re available, you may see this under More options.
    In which case you may see a Restart required message. Restart your system and the update will complete.
    restart required
  • If not, continue with the steps below.

4. Download and install

  • If updates are found, they’ll start downloading automatically. Once complete, you’ll see a button that says Install or Restart now.
  • Click Install if needed and follow any prompts. Your computer will usually need a restart to finish the update. If it does, click Restart now.

5. Double-check you’re up to date

  • After restarting, go back to Windows Update and check again. If it says You’re up to date, you’re all set!
Windows up to date

Technical details

One publicly disclosed vulnerability is important to mention. This flaw in Windows BitLocker is tracked as CVE-2026-50507 (CVSS score: 6.8 out of 10) and its description states:

“a protection mechanism failure in Windows BitLocker allows an unauthorized attacker to bypass a security feature with a physical attack.”

BitLocker is a built-in Windows security feature that encrypts your entire hard drive, securing your data from unauthorized access if your device is lost or stolen. However, this vulnerability could allow an attacker with physical access to bypass BitLocker Device Encryption and gain access to encrypted data.

Another is CVE-2026-49160 (CVSS score: 7.5 out of 10) in HTTP.sys. This vulnerability can be exploited to launch a remote denial-of-service attack against major web servers using a technique called HTTP/2 Bomb.

The third to discuss is CVE-2026-45586 (CVSS score: 7.8 out of 10) in the Windows Collaborative Translation Framework (CTFMON). An attacker who successfully exploited this vulnerability could gain SYSTEM privileges. These elevation of privilege (EoP) vulnerabilities are especially valuable to attackers because they can be combined with other flaws to gain full control of a compromised system.


We don’t just report on threats—we remove them

Cybersecurity risks should never spread beyond a headline. Keep threats off your devices by downloading Malwarebytes today.

Firefox 151 packs big privacy upgrades into a small update

20 May 2026 at 13:46

Mozilla has published release notes for Firefox browser version 151.0, and this update includes several genuinely meaningful privacy and security improvements.

Three changes stand out in particular:

  • Stronger anti‑fingerprinting
  • Broader protection for local network access
  • More control over private sessions and permissions

Note that Mozilla says several Firefox 151 features are “part of a progressive roll out,” meaning they will appear for some users first and be expanded over time. So, you may not see all of them immediately.

Privacy

One of the more visible additions is a new “end private session” control in Private Browsing Mode. Instead of closing every private window to clear your traces, you now get a dedicated fire‑icon button next to the address bar that wipes the current private session’s data and immediately starts a fresh one.

End private session button
End private session button

Under the hood, this clears the usual private browsing artifacts for that session, including history, cookies, cached files, and other site data that would normally disappear only when the last private window closes.

For people who routinely mix normal and private windows, this is safer and less error‑prone than hunting down every private tab before you walk away from the machine.

Firefox 151 also tightens its defenses against browser fingerprinting in the default “Standard” Enhanced Tracking Protection (ETP) mode. Mozilla says Firefox now limits the amount of device and browser information exposed to websites in a way that reduces the number of uniquely identifiable users by about 14% overall, and by roughly 49% on macOS.

This makes it harder for trackers to pick you out of the crowd, especially on platforms with fewer users to begin with (like certain macOS configurations). This reduces the privacy risk surface by default, which makes it harder for phishing and landing pages that redirect visitors to “categorize” you.

Another important change is Firefox’s “local network access restrictions,” which are now rolling out to all users, not just those who turned Enhanced Tracking Protection to Strict.

This means that when a website wants to communicate with devices on your local network, or with apps and services running on your machine, Firefox now asks for permission first. Chrome and Edge have been rolling out similar permission prompts.

Security

Firefox 151 also quietly fixes several security vulnerabilities.

The most notable example is CVE‑2026‑8953, a sandbox escape due to a use‑after‑free in the Disability Access APIs component. While there are currently no reports of in‑the‑wild exploitation for this specific bug at the time of writing, this is the kind of bug cybercriminals love.

A use-after-free (UAF) is a software memory vulnerability where a program attempts to access a memory location after it has been freed. If the program fails to clear the pointer to that freed memory, attackers can manipulate the error to crash the system or execute arbitrary code. A memory corruption leading to a sandbox escape is exactly the kind of link attackers want to complete a browser exploit chain.

How to update

If you’re running Firefox in a home or small‑office environment, we recommend updating to Firefox 151 as soon as possible to get the fingerprinting protections, local network access prompts, and security patches.

To update Firefox:

  • Open Firefox
  • Click the menu (three stacked lines) in the upper-right corner
  • Go to Help > About Firefox
  • Firefox will automatically check for updates and begin downloading them
  • Restart the browser when prompted to complete the update

Once your Firefox browser has been updated, it will show a green checkmark along with the message: “Firefox is up to date.”

Firefox is up to date

Let’s face it, an incognito window can only do so much. 
 
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May 2026 Patch Tuesday: no zero-days but plenty to fix

13 May 2026 at 13:00

This month’s Patch Tuesday remedies 137 security vulnerabilities, including 31 marked critical by Microsoft, with no zero-days actively exploited in the wild.

Microsoft defines a zero-day as “a flaw in software for which no official patch or security update is available yet.” This month, Microsoft has not observed any included vulnerability being exploited in production environments.

Still, this release is far from low-risk. A large chunk of the critical bugs allow remote code execution (RCE) across Windows services, Office, Azure, SharePoint, and graphics components. That means attackers who trick a user into opening a malicious document or lure them into connecting to a malicious service could gain full control of a system.

Two vulnerabilities to prioritize

From that list, we selected two that look like they could cause some trouble.

First is CVE-2026-40361, which has a CVSS score of 8.4 out of 10. It’s described as a critical use-after-free vulnerability in Microsoft Word that could allow an attacker to execute code locally on the affected system.

Use-after-free is a class of vulnerability caused by incorrect use of dynamic memory during a program’s operation. If, after freeing a memory location, a program does not clear the pointer to that memory, an attacker may be able to use the error to manipulate the program.

So, if an attacker convinces a user to open a malicious Word document, or even previews the file, they could execute arbitrary code with the privileges of the current user. That’s often enough to install malware, steal credentials, or move laterally through a network.

Second is CVE-2026-35421 (CVSS score 7.8 out of 10). This is a critical heap-based buffer overflow in Windows Graphics Device Interface (GDI). A buffer overflow occurs when an area of memory within a software application reaches its address boundary and writes into an adjacent memory region. Microsoft notes:

“For this vulnerability to be exploited, a user would need to open or otherwise process a specially crafted Enhanced Metafile (EMF) file using Microsoft Paint. This action is necessary to trigger the affected graphics functionality in the Windows component.”


Real-time protection. Zero effort. 


How to apply fixes and check if you’re protected

These updates fix security problems and keep your Windows PC protected. Here’s how to make sure you’re up to date:

1. Open Settings

  • Click the Start button (the Windows logo at the bottom left of your screen).
  • Click on Settings (it looks like a little gear).

2. Go to Windows Update

  • In the Settings window, select Windows Update (usually at the bottom of the menu on the left).

3. Check for updates

  • Click the button that says Check for updates.
  • Windows will search for the latest Patch Tuesday updates.
  • If you have selected to get the latest updates as soon as they’re available, you may see this under More options.
  • In which case you may see a Restart required message. Restart your system and the update will complete.
    May restart required
  • If not, continue with the steps below.

4. Download and Install If updates are found, they’ll start downloading automatically. Once complete, you’ll see a button that says Install or Restart now.

  • Click Install if needed and follow any prompts. Your computer will usually need a restart to finish the update. If it does, click Restart now.

5. Double-check you’re up to date

  • After restarting, go back to Windows Update and check again. If it says You’re up to date, you’re all set!
Windows is up to date

We don’t just report on threats—we remove them

Cybersecurity risks should never spread beyond a headline. Keep threats off your devices by downloading Malwarebytes today.

Update WhatsApp now: Two new flaws could expose you to malicious files

5 May 2026 at 13:39

Meta has published a new security advisory for messaging app WhatsApp, announcing patches for two vulnerabilities.

WhatsApp has fixed two security flaws that could be abused to interfere with how media and attachments are handled on your device. There is no evidence that either bug has been exploited in the wild.

These bugs don’t automatically infect devices, but they lower the barrier for social engineering and could be chained with other vulnerabilities for more serious attacks.

Malicious messages

The first issue, tracked as CVE‑2026‑23866, affects how WhatsApp processes AI‑generated “rich response messages” that embed Instagram Reels. On affected iOS and Android versions, incomplete validation means a specially crafted message could cause the app to load media from an attacker‑controlled URL. In some cases, this could trigger operating system‑level custom URL scheme handlers.

In other words: a booby‑trapped message could prompt your device to open content from an untrusted source.

How to update WhatsApp for Android

You can easily update WhatsApp from the Google Play Store.

  1. Open the Google Play Store
  2. Search for WhatsApp Messenger
  3. Tap Update

Note: Updates may not be available immediately in all regions.

How to update WhatsApp on iOS

To update WhatsApp on iOS:

  • Open the App Store
  • Tap your profile icon
  • Scroll to find WhatsApp and tap Update

If it’s not listed, search for WhatsApp to check if an “Update” button is available.

Misleading filenames

The second bug, CVE‑2026‑23863, affects WhatsApp for Windows before version 2.3000.1032164386.258709.

In this case, WhatsApp did not correctly handle filenames containing embedded NUL bytes. This could allow a file to appear as a harmless type in the interface while actually being treated as an executable when opened. That’s a classic recipe for social engineering: “click the PDF,” but get an .exe file.

How to update WhatsApp for Windows

You can find your WhatsApp for Windows version number by clicking on your profile picture and selecting Help and feedback.

Version 2.3000.1038705703.261501
Version 2.3000.1038705703.261501

If your version number is earlier than 2.3000.1032164386.258709, update via the Microsoft Store:

  1. Click the Start menu and search for Microsoft Store to open it
  2. Click Library located at the bottom-left corner
  3. Find WhatsApp Desktop
  4. Click Get Updates or Update

Once installed, restart the app to apply the changes.

Automatic updates on Windows

My WhatsApp was already up to date because I have automatic updates turned on. Here’s how to turn it on:

  1. Click the Start menu and search for Microsoft Store to open it
  2. Select Profile (your account picture) > Settings
  3. Make sure App updates is toggled to On
Auto updates on Windows

Scammers don’t need to hack you. They just need you to click once. 

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Actively exploited cPanel bug exposes millions of websites to takeover

1 May 2026 at 12:48

Security researchers are warning about a newly discovered vulnerability in the widely used web server management software cPanel and WebHost Manager (WHM). 

This is a critical, actively exploited authentication-bypass bug in cPanel/WHM that lets attackers gain administrative access to the interface without credentials, potentially take over servers and all hosted sites.

The vulnerability, tracked as CVE-2026-41940, has been added to the Known Exploited Vulnerabilities catalog by the Cybersecurity and Infrastructure Security Agency (CISA), meaning there is evidence it is being used in real-world attacks.

Because cPanel/WHM is used by over a million sites worldwide, including banks and health organizations, the potential impact is huge. In simple terms, the bug can act like a front‑door key to a big chunk of the web’s hosting infrastructure.

cPanel released patches on April 28, 2026, and urged all customers and hosts to update. It said all supported versions after 11.40 are affected, including DNSOnly and WP Squared.

Hosting providers including Namecheap, HostGator, and KnownHost temporarily blocked access to cPanel interfaces while patching, treating this as a critical authentication bypass and reporting exploit attempts going back to late February 2026.

How to stay safe

While it’s up to the hosting companies and website owners to patch as quickly as possible, there are ways to reduce your risk if a site you use is compromised.

As always, limit the data you share with websites to what’s absolutely necessary. Data they don’t have can’t be stolen.

When ordering from an online retailer, don’t tick the box to save your card details for future purchases as they will be stored on the server.

If there’s an option to check out as a guest, use it. It reduces the amount of personal data tied to an account.

Don’t reuse passwords. When one site is compromised, having the same credentials in several places turns it into a multi‑account takeover problem. A password manager can help you create complex unique passphrases, and remember them for you.

Where possible, pay by credit card. In many regions, this gives you stronger fraud protection.


Personal Data Remover

Your details are probably already for sale. 


When a site you trust gets hacked

If you think you’ve been affected by a data breach, take the following steps:

  • Check the company’s advice. Every breach is different, so check with the company to find out what’s happened and follow any specific advice it offers.
  • Change your password. You can make a stolen password useless to thieves by changing it. Choose a strong password that you don’t use for anything else. Better yet, let a password manager choose one for you.
  • Enable two-factor authentication (2FA). If you can, use a FIDO2-compliant hardware key, laptop, or phone as your second factor. Some forms of 2FA can be phished just as easily as a password, but 2FA that relies on a FIDO2 device can’t be phished.
  • Watch out for impersonators. The thieves may contact you posing as the breached platform. Check the official website to see if it’s contacting victims and verify the identity of anyone who contacts you using a different communication channel.
  • Take your time. Phishing attacks often impersonate people or brands you know, and use themes that require urgent attention, such as missed deliveries, account suspensions, and security alerts.
  • Consider not storing your card details. It’s definitely more convenient to let sites remember your card details, but it increases risk if a retailer suffers a breach.
  • Set up identity monitoring, which alerts you if your personal information is found being traded illegally online and helps you recover after.

What do cybercriminals know about you?

Use Malwarebytes’ free Digital Footprint scan to see whether your personal information has been exposed online.

Microsoft won’t patch PhantomRPC: Feature or bug?

29 April 2026 at 15:27

A researcher has discovered a weakness called PhantomRPC that Microsoft does not consider a vulnerability it plans to patch.

PhantomRPC involves Windows Remote Procedure Call (RPC), the core of communication between Windows processes. The vulnerability lets a process with impersonation rights escalate to SYSTEM by impersonating high‑privileged clients that connect to a fake RPC server.

The researcher presented a detailed technical report outlining five exploitation paths, including coercion, user interaction, or background services. They warned that potential vectors are “effectively unlimited” because the root issue is architectural.

Microsoft, however, classified the issue as “moderate,” refused a bounty, declined to assign a CVE (a spot in the list of Common Vulnerabilities and Exposures), and closed the case without tracking. Its position is that the technique requires an already‑compromised machine and does not provide unauthenticated or remote access.

Experts disagreed with Microsoft’s assessment. Their concern is that Microsoft is downplaying a systemic local privilege escalation technique that exists in all supported Windows versions.

The issue

At the core of this issue is that the Windows RPC runtime does not sufficiently verify that the server a high‑privileged client connects to is the intended legitimate endpoint.

If a legitimate RPC server is not reachable (for example because the service stopped, was misconfigured, not installed, or due to a race condition), an attacker with SeImpersonatePrivilege can spin up a fake RPC server that “fills the gap” using the same interface and endpoint.

When a SYSTEM or high‑privileged client connects to this fake server, using an impersonation level that allows the server to impersonate the client, the attacker can call RpcImpersonateClient and immediately escalate their privileges to SYSTEM.

From Microsoft’s perspective, the ability to run a rogue RPC server in this way falls under the category of “already compromised.”

SeImpersonatePrivilege

To understand the issue better, we need to dig into what SeImpersonatePrivilege does.

Basically, SeImpersonatePrivilege is the Windows permission that lets a program “pretend to be you” after you’ve already logged in, so it can do things on your behalf using your level of access.

It’s needed because many system services and server‑type apps (file sharing, RPC servers, COM servers, web apps) have to perform actions on behalf of a user, like reading their files or applying group policy.

If an attacker gains this privilege, they can create a fake service or server and wait for a more powerful account to talk to it. When that high‑privilege service connects, the attacker can grab its security token and impersonate it, effectively upgrading from an account with lower privileges to full SYSTEM control on that machine.

Protection

A Microsoft spokesperson provided the following statement:

“This technique requires an already-compromised machine and does not grant unauthenticated or remote access. Any update is a balance between existing compatibility and customer risk, and we remain committed to continually hardening our products. We recommend customers follow security best practices, including limiting administrative privileges and applying the principle of least privilege.”

In our opinion, mitigating PhantomRPC properly would require deep changes to the RPC architecture, which is hard to do on existing Windows versions without breaking compatibility. It’s maybe something we’ll see in future versions, given the scale of change needed.

What you can do:

  • As PhantomRPC is a piece in a larger chain, it is still very important to keep Windows updated.
  • Use your admin account sparingly and only for the tasks that need that kind of privilege.
  • Use an up-to-date, real-time anti-malware solution that can detect and block suspicious privilege‑escalation activity.
  • Avoid disabling or “hardening” services blindly since a malicious service might step in their place.

To answer the question in the title: it looks like a “feature” that can be abused in many ways; one that has outlived its original threat model. Defenders have to treat them as ongoing risks, rather than one‑off CVEs.


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According to CNET. Read their review


Apple fixes iOS bug that kept deleted notifications, including chat previews

23 April 2026 at 12:27

Apple has released a software update that deals with an issue that could allow deleted notifications to be retrieved. Something that, in at least one reported case, was used by law enforcement during forensic analysis.

Apple fixed the issue in iOS and iPadOS versions 18.7.8 and 26.4.2 (check availability for your device at those links). The update deals with a singular security vulnerability, tracked as CVE-2026-28950.

Although the description is brief—“a logging issue was addressed with improved data redaction”—the impact points us in the right direction.

“Notifications marked for deletion could be unexpectedly retained on the device.”

This suggests that Apple’s bug was that iOS kept copies of notification content in an internal database for longer than intended, even after the messages “disappeared” or the app was uninstalled. In a case reported by 404 Media, law enforcement was able to recover those notifications using standard forensic tools once they had access to the unlocked device. The example in that reported case involved Signal.


Mobile protection, anywhere, anytime.


A response on X by Signal states:

“The FBI was able to forensically extract copies of incoming Signal messages from a defendant’s iPhone, even after the app was deleted, because copies of the content were saved in the device’s push notification database.”

Before we go into the update process, you may want to know that you can mute or hide notifications in Signal, which also protects them from prying eyes. In Signal, open your Settings and tap on Notifications. You can adjust several settings there. For example, I have mine set so I only see the name of the sender.

Install the update

For iOS and iPadOS users, you can check if you’re using the latest software version by going to Settings > General > Software Update. It’s also worth turning on Automatic Updates if you haven’t already. You can do that on the same screen.

Update settings on iPad
Update settings on iPad

Scammers know more about you than you think. 

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Zombie ZIP method can fool antivirus during the first scan

16 March 2026 at 17:09

A researcher published “Zombie ZIP,” a simple way to change the first part (header) of a ZIP file so it falsely claims its contents are uncompressed while they are actually compressed.

Many antivirus products trust that header and never properly decompress or inspect the real payload. In tests conducted about a week after disclosure, around 60 of 63 common antivirus suites failed to detect malware hidden this way—roughly 95% of engines let it pass.

Zombie ZIP is essentially a method to create a malformed ZIP file that can bypass detection by most antivirus scanners. The technique has a major caveat, though. The malformed ZIP file requires a custom loader to open it correctly. Any normal archive utility like the built-in Windows extractor, 7-zip, WinRAR, and others will also flag the file as malformed.

The vulnerability is tracked as CVE-2026-0866, although several cybersecurity researchers dispute whether it should be categorized as a vulnerability or assigned a CVE at all. The fact that it requires a custom loader makes it almost impossible for this method to infect a system that is not already compromised.

It still allows anti-malware solutions to detect both the custom loader and any known malware once the payload is properly decompressed. In other words, the bypass only affects the initial inspection of the ZIP file, not the actual execution of already known malware.

Malwarebytes/ThreatDown products detected both files, by the way.

Malwarebytes detects Zombie ZIPs

Technical details

On their GitHub page (currently blocked by Malwarebytes Browser Guard due to a risky pattern), the researchers explain how the Zombie ZIP method works.

By changing the file’s compressiontype to 0 (STORED), tools trying to read the archive assume the file’s contents are simply stored inside the ZIP file and not compressed.

“AV engines trust the ZIP Method field. When Method=0 (STORED), they scan the data as raw uncompressed bytes. But the data is actually DEFLATE compressed — so the scanner sees compressed noise and finds no signatures.

The CRC is set to the uncompressed payload’s checksum, creating an additional mismatch that causes standard extraction tools (7-Zip, unzip, WinRAR) to report errors or extract corrupted output.

However, a purpose-built loader that ignores the declared method and decompresses as DEFLATE recovers the payload perfectly.

The vulnerability is scanner evasion: security controls assert ‘no malware present’ while malware is present and trivially recoverable by attacker tooling.”

Security researcher Didier Stevens published a method to safely examine the content of a malformed Zombie ZIP file. One way to spot the manipulation is by comparing the ZIP header fields compressedsize and uncompressedsize. If they are different, that means the ZIP file is not actually STORED, but compressed.


We don’t just report on threats—we remove them

Cybersecurity risks should never spread beyond a headline. Keep threats off your devices by downloading Malwarebytes today.

A week in security (March 9 – March 15)

16 March 2026 at 08:16

Last week on Malwarebytes Labs:

Stay safe!


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Cybersecurity risks should never spread beyond a headline. If something looks dodgy to you, check if it’s a scam using Malwarebytes Scam Guard. Submit a screenshot, paste suspicious content, or share a link, text or phone number, and we’ll tell you if it’s a scam or legit. Available with Malwarebytes Premium Security for all your devices, and in the Malwarebytes app for iOS and Android.

[updated] Google patches two Chrome zero-days under active attack

13 March 2026 at 13:58

Update March 16, 2026
Earlier this week, Google incorrectly reported that an actively exploited vulnerability in Chrome had been fixed, and has now announced it will roll out a new update to protect users against the vulnerability tracked as CVE-2026-3909.

Original content:

Google has released an out-of-band security update for Chrome desktop that patches two high‑severity zero‑day vulnerabilities.

Both bugs can be exploited remotely and require only that a user visit a malicious website. Because the attack complexity is low, the vulnerabilities pose a higher real-world risk.

How to update Chrome

The latest version numbers are 146.0.7680.75/76 for Windows and macOS and 146.0.7680.75 for Linux. If your Chrome browser is on version 146.0.7680.75 or later, you’re protected from these vulnerabilities.

The easiest way to stay up to date is to allow Chrome to update automatically. However, updates can lag if you rarely close your browser, or if something interferes with the update process.

To update manually:

  1. Click the More menu (three dots)
  2. Go to Settings > About Chrome.
  3. If an update is available, Chrome will start downloading it.
  4. Restart Chrome to complete the update, and you’ll be protected against these vulnerabilities.
Chrome on Windows up to date
Chrome (on Windows) is up to date

You can also find step-by-step instructions in our guide to how to update Chrome on every operating system, which includes instructions for checking your version number.

Technical details

Google reports that it discovered and fixed both bugs internally, with patches landing within roughly two days of reporting.

CVE‑2026‑3909 is an out‑of‑bounds write vulnerability in Skia, Chrome’s 2D graphics library used to render web content and UI elements. A remote attacker can lure a user to a malicious webpage that triggers the bug, corrupts memory, and potentially achieves code execution in the browser context. Skia is an open source 2D graphics library used not only in Google Chrome but also in many other products.

CVE‑2026‑3910 is an inappropriate implementation flaw in the V8 JavaScript and WebAssembly engine. A specially crafted HTML page could allow a remote attacker to execute arbitrary code inside the V8 sandbox. V8 is the engine that Google developed for processing JavaScript, and it has seen more than its fair share of bugs.

Chrome’s Skia and V8 components are prime targets because they sit directly on the path between untrusted web content and the underlying system.

It is possible to chain an out‑of‑bounds write in Skia with other bugs to break out of the renderer sandbox, while V8 implementation flaws frequently appear in exploit chains used by targeted threat actors and spyware vendors.

How to stay safe

To protect your device, update Chrome as soon as possible. Here are some more tips to avoid becoming a victim, even before a zero-day is patched:

  • Don’t click on unsolicited links in emails, messages, unknown websites, or on social media.
  • Enable automatic updates and restart regularly. Many users leave browsers open for days, which delays protection even if the update is downloaded in the background.
  • Use an up-to-date, real-time anti-malware solution which includes a web protection component.

Users of other Chromium-based browsers can expect to see a similar update soon.


We don’t just report on threats—we remove them

Cybersecurity risks should never spread beyond a headline. Keep threats off your devices by downloading Malwarebytes today.

Apple patches Coruna exploit kit flaws for older iOS versions

12 March 2026 at 18:49

On March 3, 2026, Google warned about a powerful exploit kit targeting Apple iPhone models running iOS version 13.0 (released in September 2019) up to version 17.2.1 (released in December 2023).

In the latest security updates, Apple patched the vulnerabilities used in the Coruna exploit kit for older mobile devices that can no longer be updated to the latest iOS version. For newer iOS versions, patches associated with the Coruna exploit were already shipped in iOS 16.6 through 17.2 in updates released in 2023 and 2024.

The Coruna exploit kit was first observed in highly targeted attacks, but was later seen in watering hole attacks targeting Ukrainian users by a suspected Russian espionage group. Later still, it appeared on a very large set of fake Chinese financial websites, suggesting the exploit was being used by more mainstream cybercriminals.

The exploit relies on WebKit vulnerabilities (CVE-2023-43000 and CVE-2024-23222) that can be triggered by processing  maliciously crafted web content, and then gains kernel privileges by abusing a separate kernel vulnerability tracked as CVE-2023-41974.

The table below shows which updates are available and points you to the relevant security content for that operating system (OS).

iOS 16.7.15 and iPadOS 16.7.15iPhone 8, iPhone 8 Plus, iPhone X, iPad (5th generation), iPad Pro 9.7-inch, and iPad Pro 12.9-inch (1st generation)
iOS 15.8.7 and iPadOS 15.8.7iPhone XS, iPhone XS Max, iPhone XR, iPad (7th generation)

How to update your iPhone or iPad

For iOS and iPadOS users, here’s how to check if you’re using the latest software version:

  • Go to Settings > General > Software Update. You will see if there are updates available and be guided through installing them.
  • Turn on Automatic Updates if you haven’t already. You’ll find it on the same screen.

We don’t just report on phone security—we provide it

Cybersecurity risks should never spread beyond a headline. Keep threats off your mobile devices by downloading Malwarebytes for iOS, and Malwarebytes for Android today.

This Android vulnerability can break your lock screen in under 60 seconds

12 March 2026 at 14:13

A vulnerability in Android devices can allow attackers to gain access to a phone in less than a minute.

The vulnerability, tracked as CVE-2026-20435, affects certain MediaTek SoCs (System-on-a-Chip) using Trustonic’s TEE (Trusted Execution Environment). That may sound rare, but reportedly that’s about one in four Android phones, mostly cheaper models.

Researchers demonstrated the vulnerability by connecting a vulnerable phone to a laptop over USB, showing how their exploit recovered the handset PIN, decrypted storage, and extracted seed phrases from several software wallets.

You may argue that if an attacker has your phone, you’re already in trouble. Which is true. But the protection you rely on to keep your data safe if your phone is lost or stolen doesn’t help one bit here.

The exploit was able to extract the root keys protecting full‑disk encryption before Android fully boots and then decrypt storage. While full‑disk encryption and lock screen are supposed to be your safety net if the phone is stolen or lost, those layers fail on affected devices.

Is my phone affected?

If you’re not sure whether this vulnerability affects your mobile device, you can look up your phone on a platform like GSMArena  or your vendor’s website to see which SoC it uses, then cross‑check with MediaTek’s March Security bulletin under CVE-2026-20435.

MediaTek released a firmware patch that device manufacturers can include in security updates for their phones. So all you can do is make sure you’re fully patched with the latest security update from your manufacturer. Which, depending on the patch gaps and how far along your device is in the EOL cycle, can take anywhere from days to forever.

EOL (End-of-Life) refers to the point in a product’s lifecycle when the manufacturer stops selling, marketing, or providing full support for it.

But obviously the best advice we can give you is to keep a close eye on your phone, so it doesn’t get lost or stolen.


We don’t just report on phone security—we provide it

Cybersecurity risks should never spread beyond a headline. Keep threats off your mobile devices by downloading Malwarebytes for iOS, and Malwarebytes for Android today.

Microsoft Authenticator could leak login codes—update your app now

12 March 2026 at 11:24

A vulnerability in Microsoft Authenticator for both iOS and Android (CVE-2026-26123) could leak your one-time sign-in codes or authentication deep links to a malicious app on the same device. 

Deep links are predefined URIs (Uniform Resource Identifiers) that allow direct access to an activity in a web or mobile application when clicked. In simple terms, they are specifically constructed links used to open an app and complete actions like signing in.

Microsoft Authenticator is a mobile app that generates time-based one-time codes and handles sign-in links and QR-based logins for Microsoft and other accounts. It is widely used for multi-factor authentication (MFA) on personal phones, including BYOD (Bring Your Own Device) devices that protect access to corporate and production services.

This vulnerability affects users who have Microsoft Authenticator installed on an iOS or Android device. For the vulnerability to be exploited, the user would first need to install a malicious app on their device and then accidentally choose that app to handle a sign‑in deep link.

If that happens, the malicious app receives the one-time code or sign-in information and can potentially use it to authenticate as the victim.​

If successful, an attacker could:

  • Complete login flows to services that trust your Microsoft Authenticator codes.
  • Access the information and services available to the compromised account (email, files, cloud apps, or production systems in a BYOD context).​
  • Potentially pivot to additional accounts if those are also protected by codes delivered via Authenticator on the same device.

How to stay safe

The fix for CVE-2026-26123 is already included in current releases, so installing updates is the most effective mitigation.

  • On iOS: Open the App Store. Tap the My Account button or your photo at the top of the screen. Scroll down to see pending updates and release notes. Tap Update next to an app to update only that app, or tap Update All.
  • On Android: Open the Google Play Store app. At the top right, tap the profile icon. Tap Manage apps & device. Under “Updates available,” tap See details. Next to the app you want to update, tap Update. To update all your apps at the same time, tap Update all.

Note: If your device manufacturer has implemented a different method to apply app updates, the steps may vary slightly.

If you are temporarily unable to update the app, avoid installing new apps that request to handle authentication links, QR-based sign-ins, or web-to-app sign-in flows.

When scanning QR codes or tapping sign-in links, verify that the handler is Microsoft Authenticator or another trusted app, and not an unknown, recently installed, or otherwise suspicious app.​

Where possible, use alternative MFA options you already trust (such as built-in authentication in your password manager or platform-specific solutions like Apple’s password features) until you can apply the update.

Use anti-malware protection for your mobile devices that can help detect malicious apps.


We don’t just report on phone security—we provide it

Cybersecurity risks should never spread beyond a headline. Keep threats off your mobile devices by downloading Malwarebytes for iOS, and Malwarebytes for Android today.

March 2026 Patch Tuesday fixes two zero-day vulnerabilities

11 March 2026 at 11:47

Microsoft releases important security updates on the second Tuesday of every month, known as Patch Tuesday. This month’s update fixes 79 Microsoft CVEs including two zero-day vulnerabilities.

Microsoft defines a zero-day as “a flaw in software for which no official patch or security update is available yet.” So, since the patch is now available, those two are no longer zero-days. There is also no reason to believe they were ever actively exploited.

But let’s have a look at the possible consequences if you don’t install the update.

The vulnerability tracked as CVE-2026-21262 (CVSS score 8.8 out of 10) is a bug in Microsoft SQL Server that lets a logged-in user quietly climb the privilege ladder and potentially become a full database administrator (sysadmin). With that level of control, they can read, change, or delete data, create new accounts, and tamper with database configurations or jobs. Where SQL Server is supposed to check what each user is allowed to do, in this case it can be tricked into granting more power than intended.

There is no user interaction required once the attacker has that foothold: exploitation can happen over the network using crafted SQL requests that abuse the flawed permission checks. In a typical real‑world scenario, this bug would be the second act in an attack chain: first get in with low privileges, then use CVE-2026-21262 to quietly promote yourself to database king and start rewriting the script.

CVE-2026-26127 (CVSS score 7.5 out of 10) is a bug in Microsoft’s .NET platform that lets an attacker remotely crash .NET applications, effectively taking them offline for a while. The flaw lives in Microsoft .NET 9.0 and 10.0, across Windows, macOS, and Linux, in the .NET runtime or libraries, not in a specific app. In other words, it’s a bug in the engine that runs .NET code, so any app created with affected .NET versions could be at risk until patched.

The main outcome is denial of service: an attacker can cause targeted .NET processes to crash or become unstable, leading to downtime or degraded performance. For a public‑facing web API, a payment service, or any line‑of‑business app built on .NET, this can mean real‑world outages and angry users while services are repeatedly knocked over.

Vulnerabilities affecting Microsoft Office users are two remote code execution flaws in Microsoft Office (CVE-2026-26110 and CVE-2026-26113) which can both be exploited via the preview pane, and a Microsoft Excel information disclosure flaw (CVE-2026-26144), which could be used to exfiltrate data via Microsoft Copilot. Office vulnerabilities appear regularly in Patch Tuesday releases, and in this case none have been reported as actively exploited.

How to apply fixes and check if you’re protected

These updates fix security problems and keep your Windows PC protected. Here’s how to make sure you’re up to date:

1. Open Settings

  • Click the Start button (the Windows logo at the bottom left of your screen).
  • Click on Settings (it looks like a little gear).

2. Go to Windows Update

  • In the Settings window, select Windows Update (usually at the bottom of the menu on the left).

3. Check for updates

  • Click the button that says Check for updates.
  • Windows will search for the latest Patch Tuesday updates.
  • If you have selected to get the latest updates as soon as they’re available, you may see this under More options.
  • In which case you may see a Restart required message. Restart your system and the update will complete.
    Restart now to apply patches
  • If not, continue with the steps below.

4. Download and Install

  • If updates are found, they’ll start downloading right away. Once complete, you’ll see a button that says Install or Restart now.
  • Click Install if needed and follow any prompts. Your computer will usually need a restart to finish the update. If it does, click Restart now.
    Windows up to date

5. Double-check you’re up to date

  • After restarting, go back to Windows Update and check again. If it says You’re up to date, you’re all set!

We don’t just report on threats—we remove them

Cybersecurity risks should never spread beyond a headline. Keep threats off your devices by downloading Malwarebytes today.

Apple patches zero-day flaw that could let attackers take control of devices

12 February 2026 at 12:40

Apple has released security updates for iPhones, iPads, Macs, Apple Watches, Apple TVs, and Safari, fixing, in particular, a zero-day flaw that is actively exploited in targeted attacks.

Exploiting this zero-day flaw would allow cybercriminals to run any code they want on the affected device, potentially installing spyware or backdoors without the owner noticing.

Installing these updates as soon as possible keeps your personal information—and everything else on your Apple devices—safe from such an attack.

CVE-2026-20700

The zero-day vulnerability tracked as CVE-2026-20700, is a memory corruption issue in versions before watchOS 26.3, tvOS 26.3, macOS Tahoe 26.3, visionOS 26.3, iOS 26.3 and iPadOS 26.3. An attacker with memory write capability may be able to execute arbitrary code.

Apple says the vulnerability was used as part of an infection chain combined with CVE-2025-14174 and CVE-2025-43529 against devices running iOS versions prior to iOS 26.

Those two vulnerabilities were already patched in the December 2025 update.

Updates for your particular device

The table below shows which updates are available and points you to the relevant security content for that operating system (OS).

iOS 26.3 and iPadOS 26.3iPhone 11 and later, iPad Pro 12.9-inch 3rd generation and later, iPad Pro 11-inch 1st generation and later, iPad Air 3rd generation and later, iPad 8th generation and later, and iPad mini 5th generation and later
iOS 18.7.5 and iPadOS 18.7.5iPhone XS, iPhone XS Max, iPhone XR, iPad 7th generation
macOS Tahoe 26.3macOS Tahoe
macOS Sequoia 15.7.4macOS Sequoia
macOS Sonoma 14.8.4macOS Sonoma
tvOS 26.3Apple TV HD and Apple TV 4K (all models)
watchOS 26.3Apple Watch Series 6 and later
visionOS 26.3Apple Vision Pro (all models)
Safari 26.3macOS Sonoma and macOS Sequoia

How to update your Apple devices

How to update your iPhone or iPad

For iOS and iPadOS users, here’s how to check if you’re using the latest software version:

  • Go to Settings > General > Software Update. You will see if there are updates available and be guided through installing them.
  • Turn on Automatic Updates if you haven’t already—you’ll find it on the same screen.
iPadOS 26.3 update

How to update macOS on any version

To update macOS on any supported Mac, use the Software Update feature, which Apple designed to work consistently across all recent versions. Here are the steps:

  • Click the Apple menu in the upper-left corner of your screen.
  • Choose System Settings (or System Preferences on older versions).
  • Select General in the sidebar, then click Software Update on the right. On older macOS, just look for Software Update directly.
  • Your Mac will check for updates automatically. If updates are available, click Update Now (or Upgrade Now for major new versions) and follow the on-screen instructions. Before you upgrade to macOS Tahoe 26, please read these instructions.
  • Enter your administrator password if prompted, then let your Mac finish the update (it might need to restart during this process).
  • Make sure your Mac stays plugged in and connected to the internet until the update is done.

How to update Apple Watch

Ensure your iPhone is paired with your Apple Watch and connected to Wi-Fi, then:

  • Keep your Apple Watch on its charger and close to your iPhone.
  • Open the Watch app on your iPhone.
  • Tap General > Software Update.
  • If an update appears, tap Download and Install.
  • Enter your iPhone passcode or Apple ID password if prompted.

Your Apple Watch will automatically restart during the update process. Make sure it remains near your iPhone and on charge until the update completes.

How to update Apple TV

Turn on your Apple TV and make sure it’s connected to the internet, then:

  • Open the Settings app on Apple TV.
  • Navigate to System > Software Updates.
  • Select Update Software.
  • If an update appears, select Download and Install.

The Apple TV will download the update and restart as needed. Keep your device connected to power and Wi-Fi until the process finishes.

How to update your Safari browser

Safari updates are included with macOS updates, so installing the latest version of macOS will also update Safari. To check manually:

  • Open the Apple menu > System Settings > General > Software Update.
  • If you see a Safari update listed separately, click Update Now to install it.
  • Restart your Mac when prompted.

If you’re on an older macOS version that’s still supported (like Sonoma or Sequoia), Apple may offer Safari updates independently through Software Update.

More advice to stay safe

The most important fix—however inconvenient it may be—is to upgrade to iOS 26.3 (or the latest available version for your device). Not doing so means missing an accumulating list of security fixes, leaving your device vulnerable to newly found vulnerabilities.

 But here are some other useful tips:

  • Make it a habit to restart your device on a regular basis.
  • Do not open unsolicited links and attachments without verifying with the trusted sender.
  • Remember: Apple threat notifications will never ask users to click links, open files, install apps or ask for account passwords or verification codes.
  • For Apple Mail users, these vulnerabilities create risk when viewing HTML-formatted emails containing malicious web content.
  • Malwarebytes for iOS can help keep your device secure, with Trusted Advisor alerting you when important updates are available.
  • If you are a high-value target, or you want the extra level of security, consider using Apple’s Lockdown Mode.

We don’t just report on phone security—we provide it

Cybersecurity risks should never spread beyond a headline. Keep threats off your mobile devices by downloading Malwarebytes for iOS, and Malwarebytes for Android today.

February 2026 Patch Tuesday includes six actively exploited zero-days

11 February 2026 at 13:32

Microsoft releases important security updates on the second Tuesday of every month, known as “Patch Tuesday.” This month’s update patches fix 59 Microsoft CVE’s including six zero-days.

Let’s have a quick look at these six actively exploited zero-days.

Windows Shell Security Feature Bypass Vulnerability

CVE-2026-21510 (CVSS score 8.8 out of 10) is a security feature bypass in the Windows Shell. A protection mechanism failure allows an attacker to circumvent Windows SmartScreen and similar prompts once they convince a user to open a malicious link or shortcut file.

The vulnerability is exploited over the network but still requires on user interaction. The victim must be socially engineered into launching the booby‑trapped shortcut or link for the bypass to trigger. Successful exploitation lets the attacker suppress or evade the usual “are you sure?” security dialogs for untrusted content, making it easier to deliver and execute further payloads without raising user suspicion.

MSHTML Framework Security Feature Bypass Vulnerability

CVE-2026-21513 (CVSS score 8.8 out of 10) affects the MSHTML Framework, which is used by Internet Explorer’s Trident/embedded web rendering). It is classified as a protection mechanism failure that results in a security feature bypass over the network.

A successful attack requires the victim to open a malicious HTML file or a crafted shortcut (.lnk) that leverages MSHTML for rendering. When opened, the flaw allows an attacker to bypass certain security checks in MSHTML, potentially removing or weakening normal browser or Office sandbox or warning protections and enabling follow‑on code execution or phishing activity.

Microsoft Word Security Feature Bypass Vulnerability

CVE-2026-21514 (CVSS score 5.5 out of 10) affects Microsoft Word. It relies on untrusted inputs in a security decision, leading to a local security feature bypass.  

An attacker must persuade a user to open a malicious Word document to exploit this vulnerability. If exploited, the untrusted input is processed incorrectly, potentially bypassing Word’s defenses for embedded or active content—leading to execution of attacker‑controlled content that would normally be blocked.

Desktop Window Manager Elevation of Privilege Vulnerability

CVE-2026-21519 (CVSS score 7.8 out of 10) is a local elevation‑of‑privilege vulnerability in Windows Desktop Window Manager caused by type confusion (a flaw where the system treats one type of data as another, leading to unintended behavior).

A locally authenticated attacker with low privileges and no required user interaction can exploit the issue to gain higher privileges. Exploitation must be done locally, for example via a crafted program or exploit chain stage running on the target system. An attacker who successfully exploited this vulnerability could gain SYSTEM privileges.

Windows Remote Access Connection Manager Denial of Service Vulnerability

CVE-2026-21525 (CVSS score 6.2 out of 10) is a denial‑of‑service vulnerability in the Windows Remote Access Connection Manager service (RasMan).

An unauthenticated local attacker can trigger the flaw with low attack complexity, leading to a high impact on availability but no direct impact on confidentiality or integrity. This means they could crash the service or potentially the system, but not elevate privileges or execute malicious code.

Windows Remote Desktop Services Elevation of Privilege Vulnerability

CVE-2026-21533 (CVSS score 7.8 out of 10) is an elevation‑of‑privilege vulnerability in Windows Remote Desktop Services, caused by improper privilege management.

A local authenticated attacker with low privileges, and no required user interaction, can exploit the flaw to escalate privileges to SYSTEM and fully compromise confidentiality, integrity, and availability on the affected system. Successful exploitation typically involves running attacker‑controlled code on a system with Remote Desktop Services present and abusing the vulnerable privilege management path.

Azure vulnerabilities

Azure users are also advised to take note of two critical vulnerabilities with CVSS ratings of 9.8:

How to apply fixes and check you’re protected

These updates fix security problems and keep your Windows PC protected. Here’s how to make sure you’re up to date:

1. Open Settings

  • Click the Start button (the Windows logo at the bottom left of your screen).
  • Click on Settings (it looks like a little gear).

2. Go to Windows Update

  • In the Settings window, select Windows Update (usually at the bottom of the menu on the left).

3. Check for updates

  • Click the button that says Check for updates.
  • Windows will search for the latest Patch Tuesday updates.
  • If you have selected automatic updates earlier, you may see this under Update history:
list of recent updates
  • Or you may see a Restart required message, which means all you have to do is restart your system and you’re done updating.
  • If not, continue with the steps below.

4. Download and Install

  • If updates are found, they’ll start downloading right away. Once complete, you’ll see a button that says Install or Restart now.
  • Click Install if needed and follow any prompts. Your computer will usually need a restart to finish the update. If it does, click Restart now.

5. Double-check you’re up to date

  • After restarting, go back to Windows Update and check again. If it says You’re up to date, you’re all set!
You're up to date

We don’t just report on threats—we remove them

Cybersecurity risks should never spread beyond a headline. Keep threats off your devices by downloading Malwarebytes today.

AI chat app leak exposes 300 million messages tied to 25 million users

9 February 2026 at 16:17

An independent security researcher uncovered a major data breach affecting Chat & Ask AI, one of the most popular AI chat apps on Google Play and Apple App Store, with more than 50 million users.

The researcher claims to have accessed 300 million messages from over 25 million users due to an exposed database. These messages reportedly included, among other things, discussions of illegal activities and requests for suicide assistance.

Behind the scenes, Chat & Ask AI is a “wrapper” app that plugs into various large language models (LLMs) from other companies, including OpenAI’s ChatGPT, Anthropic’s Claude, and Google’s Gemini. Users can choose which model they want to interact with.

The exposed data included user files containing their entire chat history, the models used, and other settings. But it also revealed data belonging to users of other apps developed by Codeway—the developer of Chat & Ask AI.

The vulnerability behind this data breach is a well-known and documented Firebase misconfiguration. Firebase is a cloud-based backend-as-a-service (BaaS) platform provided by Google that helps developers build, manage, and scale mobile and web applications.

Security researchers often refer to a set of preventable errors in how developers set up Google Firebase services, which leave backend data, databases, and storage buckets accessible to the public without authentication.

One of the most common Firebase misconfigurations is leaving Security Rules set to public. This allows anyone with the project URL to read, modify, or delete data without authentication.

This prompted the researcher to create a tool that automatically scans apps on Google Play and Apple App Store for this vulnerability—with astonishing results. Reportedly, the researcher, named Harry, found that 103 out of 200 iOS apps they scanned had this issue, collectively exposing tens of millions of stored files. 

To draw attention to the issue, Harry set up a website where users can see the apps affected by the issue. Codeway’s apps are no longer listed there, as Harry removes entries once developers confirm they have fixed the problem. Codeway reportedly resolved the issue across all of its apps within hours of responsible disclosure.

How to stay safe

Besides checking if any apps you use appear in Harry’s Firehound registry, there are a few ways to better protect your privacy when using AI chatbots.

  • Use private chatbots that don’t use your data to train the model.
  • Don’t rely on chatbots for important life decisions. They have no experience or empathy.
  • Don’t use your real identity when discussing sensitive subjects.
  • Keep shared information impersonal. Don’t use real names and don’t upload personal documents.
  • Don’t share your conversations unless you absolutely have to. In some cases, it makes them searchable.
  • If you’re using an AI that is developed by a social media company (Meta AI, Llama, Grok, Bard, Gemini, and so on), make sure you’re not logged in to that social media platform. Your conversations could be linked to your social media account, which might contain a lot of personal information.

Always remember that the developments in AI are going too fast for security and privacy to be baked into technology. And that even the best AIs still hallucinate.


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Microsoft Office zero-day lets malicious documents slip past security checks

29 January 2026 at 15:53

Microsoft issued an emergency patch for a high-severity zero-day vulnerability in Office that allows attackers to bypass document security checks and is being exploited in the wild via malicious files.

Microsoft pushed the emergency patch for the zero‑day, tracked as CVE-2026-21509, and classified it as a “Microsoft Office Security Feature Bypass Vulnerability” with a CVSS score of 7.8 out of 10.

The flaw allows attackers to bypass Object Linking and Embedding (OLE) mitigations that are designed to block unsafe COM/OLE controls inside Office documents. This means a malicious attachment could infect a PC despite built-in protections.

In a real-life scenario, an attacker creates a fake Word, Excel, or PowerPoint file containing hidden “mini‑programs” or special objects. They can run code and do other things on the affected computer. Normally, Office has safety checks that would block those mini-programs because they’re risky.

However, the vulnerability allows the attacker to tweak the file’s structure and hidden information in a way that tricks Office into thinking the dangerous mini‑program inside the document is harmless. As a result, Office skips the usual security checks and allows the hidden code to run.

As code to test the bypass is publicly available, increasing the risk of exploitation, users are under urgent advice to apply the patch.

Updating Microsoft 365 and Office
Updating Microsoft 365 and Office

How to protect your system

What you need to do depends on which version of Office you’re using.

The affected products include Microsoft Office 2016, 2019, LTSC 2021, LTSC 2024, and Microsoft 365 Apps (both 32‑bit and 64‑bit).

Office 2021 and later are protected via a server‑side change once Office is restarted. To apply it, close all Office apps and restart them.

Office 2016 and 2019 require a manual update. Run Windows Update with the option to update other Microsoft products turned on.

If you’re running build 16.0.10417.20095 or higher, no action is required. You can check your build number by opening any Office app, going to your account page, and selecting About for whichever application you have open. Make sure the build number at the top reads 16.0.10417.20095 or higher.

What always helps:

  • Don’t open unsolicited attachments without verifying them with a trusted sender.
  • Treat all unexpected documents, especially those asking to “enable content” or “enable editing,” as suspicious.
  • Keep macros disabled by default and only allow signed macros from trusted publishers.
  • Use an up-to-date real-time anti-malware solution.
  • Keep your operating system and software fully up to date.

We don’t just report on threats—we remove them

Cybersecurity risks should never spread beyond a headline. Keep threats off your devices by downloading Malwarebytes today.

A WhatsApp bug lets malicious media files spread through group chats

27 January 2026 at 12:55

WhatsApp is going through a rough patch. Some users would argue it has been ever since Meta acquired the once widely trusted messaging platform. User sentiment has shifted from “trusted default messenger” to a grudgingly necessary Meta product.

Privacy-aware users still see WhatsApp as one of the more secure mass-market messaging platforms if you lock down its settings. Even then, many remain uneasy about Meta’s broader ecosystem, and wish all their contacts would switch to a more secure platform.

Back to current affairs, which will only reinforce that sentiment.

Google’s Project Zero has just disclosed a WhatsApp vulnerability where a malicious media file, sent into a newly created group chat, can be automatically downloaded and used as an attack vector.

The bug affects WhatsApp on Android and involves zero‑click media downloads in group chats. You can be attacked simply by being added to a group and having a malicious file sent to you.

According to Project Zero, the attack is most likely to be used in targeted campaigns, since the attacker needs to know or guess at least one contact. While focused, it is relatively easy to repeat once an attacker has a likely target list.

And to put a cherry on top for WhatsApp’s competitors, a potentially even more serious concern for the popular messaging platform, an international group of plaintiffs sued Meta Platforms, alleging the WhatsApp owner can store, analyze, and access virtually all of users’ private communications, despite WhatsApp’s end-to-end encryption claims.

How to secure WhatsApp

Reportedly, Meta pushed a server change on November 11, 2025, but Google says that only partially resolved the issue. So, Meta is working on a comprehensive fix.

Google’s advice is to disable Automatic Download or enable WhatsApp’s Advanced Privacy Mode so that media is not automatically downloaded to your phone.

And you’ll need to keep WhatsApp updated to get the latest patches, which is true for any app and for Android itself.

Turn off auto-download of media

Goal: ensure that no photos, videos, audio, or documents are pulled to the device without an explicit decision.

  • Open WhatsApp on your Android device.
  • Tap the three‑dot menu in the top‑right corner, then tap Settings.
  • Go to Storage and data (sometimes labeled Data and storage usage).
  • Under Media auto-download, you will see When using mobile data, when connected on Wi‑Fi. and when roaming.
  • For each of these three entries, tap it and uncheck all media types: Photos, Audio, Videos, Documents. Then tap OK.
  • Confirm that each category now shows something like “No media” under it.

Doing this directly implements Project Zero’s guidance to “disable Automatic Download” so that malicious media can’t silently land on your storage as soon as you are dropped into a hostile group.

Stop WhatsApp from saving media to your Android gallery

Even if WhatsApp still downloads some content, you can stop it from leaking into shared storage where other apps and system components see it.

  • In Settings, go to Chats.
  • Turn off Media visibility (or similar option such as Show media in gallery). For particularly sensitive chats, open the chat, tap the contact or group name, find Media visibility, and set it to No for that thread.

WhatsApp is a sandbox, and should contain the threat. Which means, keeping media inside WhatsApp makes it harder for a malicious file to be processed by other, possibly more vulnerable components.

Lock down who can add you to groups

The attack chain requires the attacker to add you and one of your contacts to a new group. Reducing who can do that lowers risk.

  • ​In Settings, tap Privacy.
  • Tap Groups.
  • Change from Everyone to My contacts or ideally My contacts except… and exclude any numbers you do not fully trust.
  • If you use WhatsApp for work, consider keeping group membership strictly to known contacts and approved admins.

Set up two-step verification on your WhatsApp account

Read this guide for Android and iOS to learn how to do that.


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Cybersecurity risks should never spread beyond a headline. Keep threats off your mobile devices by downloading Malwarebytes for iOS, and Malwarebytes for Android today.

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