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The Government Uses Targeted Advertising to Track Your Location. Here's What We Need to Do.

5 March 2026 at 15:00

We've all had the unsettling experience of seeing an ad online that reveals just how much advertisers know about our lives. You're right to be disturbed. Those very same online ad systems have been used by the government to warrantlessly track peoples' locations, new reporting has confirmed.

For years, the internet advertising industry has been sucking up our data, including our location data, to serve us "more relevant ads." At the same time, we know that federal law enforcement agencies have been buying up our location data from shady data brokers that most people have never heard of.

Now, a new report gives us direct evidence that Customs and Border Protection (CBP) has used location data taken from the internet advertising ecosystem to track phones. In a document uncovered by 404 Media, CBP admits what we’ve been saying for years: The technical systems powering creepy targeted ads also allow federal agencies to track your location.

The document acknowledges that a program by the agency to use "commercially available marketing location data" for surveillance drew from the process used to select the targeted ads shown to you on nearly every website and app you visit. In this blog post, we'll tell you what this process is, how it can and is being used for state surveillance, and what can be done about it—by individuals, by lawmakers, and by the tech companies that enable these abuses.

Advertising Surveillance Enables Government Surveillance

The online advertising industry has built a massive surveillance machine, and the government can co-opt it to spy on us. 

In the absence of strong privacy laws, surveillance-based advertising has become the norm online. Companies track our online and offline activity, then share it with ad tech companies and data brokers to help target ads. Law enforcement agencies take advantage of this advertising system to buy information about us that they would normally need a warrant for, like location data. They rely on the multi-billion-dollar data broker industry to buy location data harvested from people’s smartphones.

We’ve known for years that location data brokers are one part of federal law enforcement's massive surveillance arsenal, including immigration enforcement agencies like CBP and Immigration and Customs Enforcement (ICE). ICE, CBP and the FBI have purchased location data from the data broker Venntell and used it to identify immigrants who were later arrested. Last year, ICE purchased a spy tool called Webloc that gathers the locations of millions of phones and makes it easy to search for phones within specific geographic areas over a period of time. Webloc also allows them to filter location data by the unique advertising IDs that Apple and Google assign to our phones.

But a document recently obtained by 404 Media is the first time CBP has acknowledged the location data it buys is partially sourced from the system powering nearly every ad you see online: real-time bidding (RTB). As CBP puts it, “RTB-sourced location data is recorded when an advertisement is served.” 

Even though this document is about a 2019-2021 pilot use of this data, CBP and other federal agencies have continued to purchase and use commercially obtained location data. ICE has purchased location tracking tools since then and recently requested information on “Ad Tech” tools it could use for investigations. 

The CBP document acknowledges two sources of location data that it relies on: software development kits (SDKs) and RTB, both methods of location-tracking that EFF has written about before. Apps for weather, navigation, dating, fitness, and “family safety” often request location permissions to enable key features. But once an app has access to your location, it could share it with data brokers directly through SDKs or indirectly (and often without the app developers' knowledge) through RTB. Data brokers can collect location data from SDKs that they pay developers to put in their apps. When relying on RTB, data brokers don’t need any direct relationship with the apps and websites they’re collecting location data from. RTB is facilitated by ad companies that are already plugged into most websites and apps. 

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How Real-Time Bidding Works

RTB is the process by which most websites and apps auction off their ad space. Unfortunately, the milliseconds-long auctions that determine which ads you see also expose your information, including location data, to thousands of companies a day. At a high-level, here’s how RTB works:

  1. The moment you visit a website or app with ad space, it asks an ad tech company to determine which ads to display for you. 
  2. This ad tech company packages all the information they can gather about you into a “bid request” and broadcasts it to thousands of potential advertisers. 
  3. The bid request may contain information like your unique advertising ID, your GPS coordinates, IP address, device details, inferred interests, demographic information, and the app or website you’re visiting. The information in bid requests is called “bidstream data” and typically includes identifiers that can be linked to real people. 
  4. Advertisers use the personal information in each bid request, along with data profiles they’ve built about you over time, to decide whether to bid on the ad space. 
  5. The highest bidder gets to display an ad for you, but advertisers (or the adtech companies that represent them) can collect your bidstream data regardless of whether or not they bid on the ad space.   

A key vulnerability of real-time bidding is that while only one advertiser wins the auction, all participants receive data about the person who would see their ad. As a result, anyone posing as an ad buyer can access a stream of sensitive data about billions of individuals a day. Data brokers have taken advantage of this vulnerability to harvest data at a staggering scale. For example, the FTC found that location data broker Mobilewalla collected data on over a billion people, with an estimated 60% sourced from RTB auctions. Leaked data from another location data broker, Gravy Analytics, referenced thousands of apps, including Microsoft apps, Candy Crush, Tinder, Grindr, MyFitnessPal, pregnancy trackers and religious-focused apps. When confronted, several of these apps’ developers said they had never heard of Gravy Analytics. 

As Venntel, one of the location data brokers that has sold to ICE, puts it, “Commercially available bidstream data from the advertising ecosystem has long been one of the most comprehensive sources of real-time location and device data available.” But the privacy harms of RTB are not just a matter of misuse by individual data brokers. RTB auctions broadcast the average person’s data to thousands of companies, hundreds of times per day, with no oversight of how this information is ultimately exploited. Once your information is broadcast through RTB, it’s almost impossible to know who receives it or control how it’s used. 

What You Can Do To Protect Yourself

Revelations about the government's exploitation of this location data shows how dangerous online tracking has become, but we’re not powerless. Here are two basic steps you can take to better protect your location data:

  1. Disable your mobile advertising ID (see instructions for iPhone/Android). Apple and Google assign unique advertising IDs to each of their phones. Location data brokers use these advertising IDs to stitch together the information they collect about you from different apps. 
  2. Review apps you’ve granted location permissions to. Apps that have access to your location could share it with other companies, so make sure you’re only granting location permission to apps that really need it in order to function. If you can’t disable location access completely for an app, limit it to only when you have the app open or only approximate location instead of precise location. 

For more tips, check out EFF’s guide to protecting yourself from mobile-device based location tracking. Keep in mind that the security plan that’s best for you will vary in different situations. For example, you may want to take stronger steps to protect your location data when traveling to a sensitive location, like a protest. 

What Tech Companies and Lawmakers Must Do

Legislators and tech companies must act so that individuals don’t bear the burden of defending their data every time they use the internet.

Ad tech companies must reckon with their role in warrantless government surveillance, among other privacy harms. The systems they built for targeted advertising are actively used to track people’s location. The best way to prevent online ads from fueling surveillance is to stop targeting ads based on detailed behavioral profiles. Ads can still be targeted contextually—based on the content people are viewing—without collecting or exposing their sensitive personal information. Short of moving to contextual advertising, tech companies can limit the use of their systems for government location tracking by:

  • Stopping the use of precise location data for targeted advertising. Ad tech companies facilitating ad auctions can and should remove precise location data from bid requests. Ads can be targeted based on people’s coarse location, like the city they’re in, without giving data brokers people’s exact GPS coordinates. Precise location data can reveal where we work, where we live, who we meet, where we protest, where we worship, and more. Broadcasting it to thousands of companies a day through RTB is dangerous.
  • Removing advertising IDs from devices, or at minimum, disabling them by default. Advertising IDs have become a linchpin of the data broker economy and are actively used by law enforcement to track people’s location. Advertising IDs were added to phones in 2012 to let companies track you, and removing them is not a far-fetched idea. When Apple forced apps to request access to people’s advertising IDs starting in 2021 (if you have an iPhone you’ve probably seen the "Ask App Not to Track" pop-ups), 96% of U.S. users opted out, essentially disabling advertising IDs on most iOS devices. One study found that iPhone users were less likely to be victims of financial fraud after Apple implemented this change. Google should follow Apple’s lead and disable advertising IDs by default.

Lawmakers also need to step up to protect their constituents' privacy. We need strong, federal privacy laws to stop companies from spying on us and selling our personal information. EFF advocates for data privacy legislation with teeth and a ban on ad targeting based on online behavioral profiles, as it creates a financial incentive for companies to track our every move.

Legislators can and must also close the "data broker loophole" on the Fourth Amendment. Instead of obtaining a warrant signed by a judge, law enforcement agencies can just buy location data from private brokers to find out where you've been. Last year, Montana became the first state in the U.S. to pass a law blocking the government from buying sensitive data it would otherwise need a warrant to obtain. And in 2024, Senator Ron Wyden's EFF-endorsed Fourth Amendment is Not for Sale Act passed the House before dying in the Senate. Others should follow suit to stop this end-run around constitutional protections.

Online behavioral advertising isn’t just creepy–it’s dangerous. It's wrong that our personal information is being silently harvested, bought by shadow-y data brokers, and sold to anyone who wants to invade our privacy. This latest revelation of warrantless government surveillance should serve as a frightening wakeup call of how dangerous online behavioral advertising  has become.

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Google Settlement May Bring New Privacy Controls for Real-Time Bidding

29 January 2026 at 18:11

EFF has long warned about the dangers of the “real-time bidding” (RTB) system powering nearly every ad you see online. A proposed class-action settlement with Google over their RTB system is a step in the right direction towards giving people more control over their data. Truly curbing the harms of RTB, however, will require stronger legislative protections.

What Is Real-Time Bidding?

RTB is the process by which most websites and apps auction off their ad space. Unfortunately, the milliseconds-long auctions that determine which ads you see also expose your personal information to thousands of companies a day. At a high-level, here’s how RTB works:

  1. The moment you visit a website or app with ad space, it asks an ad tech company to determine which ads to display for you. This involves sending information about you and the content you’re viewing to the ad tech company.
  2. This ad tech company packages all the information they can gather about you into a “bid request” and broadcasts it to thousands of potential advertisers. 
  3. The bid request may contain information like your unique advertising ID, your GPS coordinates, IP address, device details, inferred interests, demographic information, and the app or website you’re visiting. The information in bid requests is called “bidstream data” and typically includes identifiers that can be linked to real people. 
  4. Advertisers use the personal information in each bid request, along with data profiles they’ve built about you over time, to decide whether to bid on the ad space. 
  5. The highest bidder gets to display an ad for you, but advertisers (and the adtech companies they use to buy ads) can collect your bidstream data regardless of whether or not they bid on the ad space.   

Why Is Real-Time Bidding Harmful?

A key vulnerability of real-time bidding is that while only one advertiser wins the auction, all participants receive data about the person who would see their ad. As a result, anyone posing as an ad buyer can access a stream of sensitive data about billions of individuals a day. Data brokers have taken advantage of this vulnerability to harvest data at a staggering scale. Since bid requests contain individual identifiers, they can be tied together to create detailed profiles of people’s behavior over time.

Data brokers have sold bidstream data for a range of invasive purposes, including tracking union organizers and political protesters, outing gay priests, and conducting warrantless government surveillance. Several federal agencies, including ICE, CBP and the FBI, have purchased location data from a data broker whose sources likely include RTB. ICE recently requested information on “Ad Tech” tools it could use in investigations, further demonstrating RTB’s potential to facilitate surveillance. RTB also poses national security risks, as researchers have warned that it could allow foreign states to obtain compromising personal data about American defense personnel and political leaders.

The privacy harms of RTB are not just a matter of misuse by individual data brokers. RTB auctions broadcast torrents of personal data to thousands of companies, hundreds of times per day, with no oversight of how this information is ultimately used. Once your information is broadcast through RTB, it’s almost impossible to know who receives it or control how it’s used. 

Proposed Settlement with Google Is a Step in the Right Direction

As the dominant player in the online advertising industry, Google facilitates the majority of RTB auctions. Google has faced several class-action lawsuits for sharing users’ personal information with thousands of advertisers through RTB auctions without proper notice and consent. A recently proposed settlement to these lawsuits aims to give people more knowledge and control over how their information is shared in RTB auctions.

Under the proposed settlement, Google must create a new privacy setting (the “RTB Control”) that allows people to limit the data shared about them in RTB auctions. When the RTB Control is enabled, bid requests will not include identifying information like pseudonymous IDs (including mobile advertising IDs), IP addresses, and user agent details. The RTB Control should also prevent cookie matching, a method companies use to link their data profiles about a person to a corresponding bid request. Removing identifying information from bid requests makes it harder for data brokers and advertisers to create consumer profiles based on bidstream data. If the proposed settlement is approved, Google will have to inform all users about the new RTB Control via email. 

While this settlement would be a step in the right direction, it would still require users to actively opt out of their identifying information being shared through RTB. Those who do not change their default settings—research shows this is most people—will remain vulnerable to RTB’s massive daily data breach. Google broadcasting your personal data to thousands of companies each time you see an ad is an unacceptable and dangerous default. 

The impact of RTB Control is further limited by technical constraints on who can enable it. RTB Control will only work for devices and browsers where Google can verify users are signed in to their Google account, or for signed-out users on browsers that allow third-party cookies. People who don't sign in to a Google account or don't enable privacy-invasive third-party cookies cannot benefit from this protection. These limitations could easily be avoided by making RTB Control the default for everyone. If the settlement is approved, regulators and lawmakers should push Google to enable RTB Control by default.

The Real Solution: Ban Online Behavioral Advertising

Limiting the data exposed through RTB is important, but we also need legislative change to protect people from the online surveillance enabled and incentivized by targeted advertising. The lack of strong, comprehensive privacy law in the U.S. makes it difficult for individuals to know and control how companies use their personal information. Strong privacy legislation can make privacy the default, not something that individuals must fight for through hidden settings or additional privacy tools. EFF advocates for data privacy legislation with teeth and a ban on ad targeting based on online behavioral profiles, as it creates a financial incentive for companies to track our every move. Until then, you can limit the harms of RTB by using EFF’s Privacy Badger to block ads that track you, disabling your mobile advertising ID (see instructions for iPhone/Android), and keeping an eye out for Google’s RTB Control.

The Breachies 2025: The Worst, Weirdest, Most Impactful Data Breaches of the Year

Another year has come and gone, and with it, thousands of data breaches that affect millions of people. The question these days is less, Is my information in a data breach this year? and more How many data breaches had my information in them this year? 

Some data breaches are more noteworthy than others. Where one might affect a small number of people and include little useful information, like a name or email address, others might include data ranging from a potential medical diagnosis to specific location information. To catalog and talk about these breaches we created the Breachies, a series of tongue-in-cheek awards, to highlight the most egregious data breaches. 

In most cases, if these companies practiced a privacy first approach and focused on data minimization, only collecting and storing what they absolutely need to provide the services they promise, many data breaches would be far less harmful to the victims. But instead, companies gobble up as much as they can, store it for as long as possible, and inevitably at some point someone decides to poke in and steal that data. Once all that personal data is stolen, it can be used against the breach victims for identity theft, ransomware attacks, and to send unwanted spam. It has become such a common occurrence that it’s easy to lose track of which breaches affect you, and just assume your information is out there somewhere. Still, a few steps can help protect your information.

With that, let’s get to the awards.

The Winners

The Say Something Without Saying Anything Award: Mixpanel

We’ve long warned that apps delivering your personal information to third-parties, even if they aren’t the ad networks directly driving surveillance capitalism, presents risks and a salient target for hackers. The more widespread your data, the more places attackers can go to find it. Mixpanel, a data analytics company which collects information on users of any app which incorporates its SDK, suffered a major breach in November this year. The service has been used by a wide array of companies, including the Ring Doorbell App, which we reported on back in 2020 delivering a trove of information to Mixpanel, and PornHub, which despite not having worked with the company since 2021, had its historical record of paying subscribers breached.    

There’s a lot we still don’t know about this data breach, in large part because the announcement about it is so opaque, leaving reporters with unanswered questions about how many were affected, if the hackers demanded a ransom, and if Mixpanel employee accounts utilized standard security best practices. One thing is clear, though: the breach was enough for OpenAI to drop them as a provider, disclosing critical details on the breach in a blog post that Mixpanel’s own announcement conveniently failed to mention.

The worst part is that, as a data analytics company providing libraries which are included in a broad range of apps, we can surmise that the vast majority of people affected by this breach have no direct relationship with Mixpanel, and likely didn’t even know that their devices were delivering data to the company. These people deserve better than vague statements by companies which profit off of (and apparently insufficiently secure) their data.

The We Still Told You So Award: Discord

Last year, AU10TIX won our first The We Told You So Award because as we predicted in 2023, age verification mandates would inevitably lead to more data breaches, potentially exposing government IDs as well as information about the sites that a user visits. Like clockwork, they did. It was our first We Told You So Breachies award, but we knew it wouldn’t be the last. 

Unfortunately, there is growing political interest in mandating identity or age verification before allowing people to access social media or adult material. EFF and others oppose these plans because they threaten both speech and privacy

Nonetheless, this year’s winner of The We Still Told You So Breachies Award is the messaging app, Discord — once known mainly for gaming communities, it now hosts more than 200 million monthly active users and is widely used to host fandom and community channels. 

In September of this year, much of Discord’s age verification data was breached — including users’ real names, selfies, ID documents, email and physical addresses, phone numbers, IP addresses, and other contact details or messages provided to customer support. In some cases, “limited billing information” was also accessed—including payment type, the last four digits of credit card numbers, and purchase histories. 

Technically though, it wasn’t Discord itself that was hacked but their third-party customer support provider — a company called Zendeskthat was compromised, allowing attackers to access Discord’s user data. Either way, it’s Discord users who felt the impact. 

The Tea for Two Award: Tea Dating Advice and TeaOnHer

Speaking of age verification, Tea, the dating safety app for women, had a pretty horrible year for data breaches. The app allows users to anonymously share reviews and safety information about their dates with men—helping keep others safe by noting red flags they saw during their date.

Since Tea is aimed at women’s safety and dating advice, the app asks new users to upload a selfie or photo ID to verify their identity and gender to create an account. That’s some pretty sensitive information that the app is asking you to trust it with! Back in July, it was reported that 72,000 images had been leaked from the app, including 13,000 images of photo IDs and 59,000 selfies. These photos were found via an exposed database hosted on Google’s mobile app development platform, Firebase. And if that isn’t bad enough, just a week later a second breach exposed private messages between users, including messages with phone numbers, abortion planning, and discussions about cheating partners. This breach included more than 1.1 million messages from early 2023 all the way to mid-2025, just before the breach was reported. Tea released a statement shortly after, temporarily disabling the chat feature.

But wait, there’s more. A completely different app based on the same idea, but for men, also suffered a data breach. TeaOnHer failed to protect similar sensitive data. In August, TechCrunch discovered that user information — including emails, usernames, and yes, those photo IDs and selfies — was accessible through a publicly available web address. Even worse? TechCrunch also found the email address and password the app’s creator uses to access the admin page.

Breaches like this are one of the reasons that EFF shouts from the rooftops against laws that mandate user verification with an ID or selfie. Every company that collects this information becomes a target for data breaches — and if a breach happens, you can’t just change your face. 

The Just Stop Using Tracking Tech Award: Blue Shield of California

Another year, another data breach caused by online tracking tools. 

In April, Blue Shield of California revealed that it had shared 4.7 million people’s health data with Google by misconfiguring Google Analytics on its website. The data, which may have been used for targeted advertising, included: people’s names, insurance plan details, medical service providers, and patient financial responsibility. The health insurance company shared this information with Google for nearly three years before realizing its mistake.

If this data breach sounds familiar, it’s because it is: last year’s Just Stop Using Tracking Tech award also went to a healthcare company that leaked patient data through tracking code on its website. Tracking tools remain alarmingly common on healthcare websites, even after years of incidents like this one. These tools are marketed as harmless analytics or marketing solutions, but can expose people’s sensitive data to advertisers and data brokers. 

EFF’s free Privacy Badger extension can block online trackers, but you shouldn’t need an extension to stop companies from harvesting and monetizing your medical data. We need a strong, federal privacy law and ban on online behavioral advertising to eliminate the incentives driving companies to keep surveilling us online. 

The Hacker's Hall Pass Award: PowerSchool

 In December 2024, PowerSchool, the largest provider of student information systems in the U.S., gave hackers access to sensitive student data. The breach compromised personal information of over 60 million students and teachers, including Social Security numbers, medical records, grades, and special education data. Hackers exploited PowerSchool’s weak security—namely, stolen credentials to their internal customer support portal—and gained unfettered access to sensitive data stored by school districts across the country.

PowerSchool failed to implement basic security measures like multi-factor authentication, and the breach affected districts nationwide. In Texas alone, over 880,000 individuals’ data was exposed, prompting the state's attorney general to file a lawsuit, accusing PowerSchool of misleading its customers about security practices. Memphis-Shelby County Schools also filed suit, seeking damages for the breach and the cost of recovery.

While PowerSchool paid hackers an undisclosed sum to prevent data from being published, the company’s failure to protect its users’ data raises serious concerns about the security of K-12 educational systems. Adding to the saga, a Massachusetts student, Matthew Lane, pleaded guilty in October to hacking and extorting PowerSchool for $2.85 million in Bitcoin. Lane faces up to 17 years in prison for cyber extortion and aggravated identity theft, a reminder that not all hackers are faceless shadowy figures — sometimes they’re just a college kid.

The Worst. Customer. Service. Ever. Award: TransUnion

Credit reporting giant TransUnion had to notify its customers this year that a hack nabbed the personal information of 4.4 million people. How'd the attackers get in? According to a letter filed with the Maine Attorney General's office obtained by TechCrunch, the problem was a “third-party application serving our U.S. consumer support operations.” That's probably not the kind of support they were looking for. 

TransUnion said in a Texas filing that attackers swept up “customers’ names, dates of birth, and Social Security numbers” in the breach, though it was quick to point out in public statements that the hackers did not access credit reports or “core credit data.” While it certainly could have been worse, this breach highlights the many ways that hackers can get their hands on information. Coming in through third-parties, companies that provide software or other services to businesses, is like using an unguarded side door, rather than checking in at the front desk. Companies, particularly those who keep sensitive personal information, should be sure to lock down customer information at all the entry points. After all, their decisions about who they do business with ultimately carry consequences for all of their customers — who have no say in the matter.

The Annual Microsoft Screwed Up Again Award: Microsoft

Microsoft is a company nobody feels neutral about. Especially in the infosec world. The myriad software vulnerabilities in Windows, Office, and other Microsoft products over the decades has been a source of frustration and also great financial rewards for both attackers and defenders. Yet still, as the saying goes: “nobody ever got fired for buying from Microsoft.” But perhaps, the times, they are a-changing. 

In July 2025, it was revealed that a zero-day security vulnerability in Microsoft’s flagship file sharing and collaboration software, SharePoint, had led to the compromise of over 400 organizations, including major corporations and sensitive government agencies such as the National Nuclear Security Administration (NNSA), the federal agency responsible for maintaining and developing the U.S. stockpile of nuclear weapons. The attack was attributed to three different Chinese government linked hacking groups. Amazingly, days after the vulnerability was first reported, there were still thousands of vulnerable self-hosted Sharepoint servers online. 

Zero-days happen to tech companies, large and small. It’s nearly impossible to write even moderately complex software that is bug and exploit free, and Microsoft can’t exactly be blamed for having a zero-day in their code. But when one company is the source of so many zero-days consistently for so many years, one must start wondering whether they should put all their eggs (or data) into a basket that company made. Perhaps if Microsoft’s monopolistic practices had been reined in back in the 1990s we wouldn’t be in a position today where Sharepoint is the defacto file sharing software for so many major organizations. And maybe, just maybe, this is further evidence that tech monopolies and centralization of data aren’t just bad for consumer rights, civil liberties, and the economy—but also for cybersecurity. 

The Silver Globe Award: Flat Earth Sun, Moon & Zodiac

Look, we’ll keep this one short: in October of last year, researchers found security issues in the flat earther app, Flat Earth, Sun, Moon, & Clock. In March of 2025, that breach was confirmed. What’s most notable about this, aside from including a surprising amount of information about gender, name, email addresses and date of birth, is that it also included users’ location info, including latitude and longitude. Huh, interesting.

The I Didn’t Even Know You Had My Information Award: Gravy Analytics

In January, hackers claimed they stole millions of people’s location history from a company that never should’ve had it in the first place: location data broker Gravy Analytics. The data included timestamped location coordinates tied to advertising IDs, which can reveal exceptionally sensitive information. In fact, researchers who reviewed the leaked data found it could be used to identify military personnel and gay people in countries where homosexuality is illegal

The breach of this sensitive data is bad, but Gravy Analytics’s business model of regularly harvesting and selling it is even worse. Despite the fact that most people have never heard of them, Gravy Analytics has managed to collect location information from a billion phones a day. The company has sold this data to other data brokers, makers of police surveillance tools, and the U.S. government

How did Gravy Analytics get this location information from people’s phones? The data broker industry is notoriously opaque, but this breach may have revealed some of Gravy Analytics’ sources. The leaked data referenced thousands of apps, including Microsoft apps, Candy Crush, Tinder, Grindr, MyFitnessPal, pregnancy trackers and religious-focused apps. Many of these app developers said they had no relationship with Gravy Analytics. Instead, expert analysis of the data suggests it was harvested through the advertising ecosystem already connected to most apps. This breach provides further evidence that online behavioral advertising fuels the surveillance industry

Whether or not they get hacked, location data brokers like Gravy Analytics threaten our privacy and security. Follow EFF’s guide to protecting your location data and help us fight for legislation to dismantle the data broker industry. 

The Keeping Up With My Cybertruck Award: Teslamate

TeslaMate, a tool meant to track Tesla vehicle data (but which is not owned or operated by Tesla itself), has become a cautionary tale about data security. In August, a security researcher found more than 1,300 self-hosted TeslaMate dashboards were exposed online, leaking sensitive information such as vehicle location, speed, charging habits, and even trip details. In essence, your Cybertruck became the star of its own Keeping Up With My Cybertruck reality show, except the audience wasn’t made up of fans interested in your lifestyle, just random people with access to the internet.

TeslaMate describes itself as “that loyal friend who never forgets anything!” — but its lack of proper security measures makes you wish it would. This breach highlights how easily location data can become a tool for harassment or worse, and the growing need for legislation that specifically protects consumer location data. Without stronger regulations around data privacy, sensitive location details like where you live, work, and travel can easily be accessed by malicious actors, leaving consumers with no recourse.

The Disorder in the Courts Award: PACER

Confidentiality is a core principle in the practice of law. But this year a breach of confidentiality came from an unexpected source: a breach of the federal court filing system. In August, Politico reported that hackers infiltrated the Case Management/Electronic Case Files (CM/ECF) system, which uses the same database as PACER, a searchable public database for court records. Of particular concern? The possibility that the attack exposed the names of confidential informants involved in federal cases from multiple court districts. Courts across the country acted quickly to set up new processes to avoid the possibility of further compromises.

The leak followed a similar incident in 2021 and came on the heels of a warning to Congress that the file system is more than a little creaky. In fact, an IT official from the federal court system told the House Judiciary Committee that both systems are “unsustainable due to cyber risks, and require replacement.”

The Only Stalkers Allowed Award: Catwatchful

Just like last year, a stalkerware company was subject to a data breach that really should prove once and for all that these companies must be stopped. In this case, Catwatchful is an Android spyware company that sells itself as a “child monitoring app.” Like other products in this category, it’s designed to operate covertly while uploading the contents of a victim’s phone, including photos, messages, and location information.

This data breach was particularly harmful, as it included not just the email addresses and passwords on the customers who purchased the app to install on a victim’s phone, but also the data from the phones of 26,000 victims’ devices, which could include the victims’ photos, messages, and real-time location data.

This was a tough award to decide on because Catwatchful wasn’t the only stalkerware company that was hit this year. Similar breaches to SpyX, Cocospy, and Spyic were all strong contenders. EFF has worked tirelessly to raise the alarm on this sort of software, and this year worked with AV Comparatives to test the stalkerware detection rate on Android of various major antivirus apps.

The Why We’re Still Stuck on Unique Passwords Award: Plex

Every year, we all get a reminder about why using unique passwords for all our accounts is crucial for protecting our online identities. This time around, the award goes to Plex, who experienced a data breach that included customer emails, usernames, and hashed passwords (which is a fancy way of saying passwords are scrambled through an algorithm, but it is possible they could still be deciphered).

If this all sounds vaguely familiar to you for some reason, that’s because a similar issue also happened to Plex in 2022, affecting 15 million users. Whoops.

This is why it is important to use unique passwords everywhereA password manager, including one that might be free on your phone or browser, makes this much easier to do. Likewise, credential stuffing illustrates why it’s important to use two-factor authentication. Here’s how to turn that on for your Plex account.

The Uh, Yes, Actually, I Have Been Pwned Award: Troy Hunt’s Mailing List

Troy Hunt, the person behind Have I Been Pwned? and who has more experience with data breaches than just about anyone, also proved that anyone can be pwned. In a blog post, he details what happened to his mailing list:

You know when you're really jet lagged and really tired and the cogs in your head are just moving that little bit too slow? That's me right now, and the penny has just dropped that a Mailchimp phish has grabbed my credentials, logged into my account and exported the mailing list for this blog.

And he continues later:

I'm enormously frustrated with myself for having fallen for this, and I apologise to anyone on that list. Obviously, watch out for spam or further phishes and check back here or via the social channels in the nav bar above for more.

The whole blog is worth a read as a reminder that phishing can get anyone, and we thank Troy Hunt for his feedback on this and other breaches to include this year.

Tips to Protect Yourself

Data breaches are such a common occurrence that it’s easy to feel like there’s nothing you can do, nor any point in trying. But privacy isn’t dead. While some information about you is almost certainly out there, that’s no reason for despair. In fact, it’s a good reason to take action.

There are steps you can take right now with all your online accounts to best protect yourself from the the next data breach (and the next, and the next):

  • Use unique passwords on all your online accounts. This is made much easier by using a password manager, which can generate and store those passwords for you. When you have a unique password for every website, a data breach of one site won’t cascade to others.
  • Use two-factor authentication when a service offers it. Two-factor authentication makes your online accounts more secure by requiring additional proof (“factors”) alongside your password when you log in. While two-factor authentication adds another step to the login process, it’s a great way to help keep out anyone not authorized, even if your password is breached.
  • Delete old accounts: Sometimes, you’ll get a data breach notification for an account you haven’t used in years. This can be a nice reminder to delete that account, but it’s better to do so before a data breach happens, when possible. Try to make it a habit to go through and delete old accounts once a year or so. 
  • Freeze your credit. Many experts recommend freezing your credit with the major credit bureaus as a way to protect against the sort of identity theft that’s made possible by some data breaches. Freezing your credit prevents someone from opening up a new line of credit in your name without additional information, like a PIN or password, to “unfreeze” the account. This might sound absurd considering they can’t even open bank accounts, but if you have kids, you can freeze their credit too.
  • Keep a close eye out for strange medical bills. With the number of health companies breached this year, it’s also a good idea to watch for healthcare fraud. The Federal Trade Commission recommends watching for strange bills, letters from your health insurance company for services you didn’t receive, and letters from debt collectors claiming you owe money. 

(Dis)Honorable Mentions

According to one report, 2025 had already seen 2,563 data breaches by October, which puts the year on track to be one of the worst by the sheer number of breaches.

We did not investigate every one of these 2,500-plus data breaches, but we looked at a lot of them, including the news coverage and the data breach notification letters that many state Attorney General offices host on their websites. We can’t award the coveted Breachies Award to every company that was breached this year. Still, here are some (dis)honorable mentions we wanted to highlight:

Salesforce, F5, Oracle, WorkComposer, Raw, Stiizy, Ohio Medical Alliance LLC, Hello Cake, Lovense, Kettering Health, LexisNexis, WhatsApp, Nexar, McDonalds, Congressional Budget Office, Doordash, Louis Vuitton, Adidas, Columbia University, Hertz, HCRG Care Group, Lexipol, Color Dating, Workday, Aflac, and Coinbase. And a special nod to last minute entrants Home Depot, 700Credit, and Petco.

What now? Companies need to do a better job of only collecting the information they need to operate, and properly securing what they store. Also, the U.S. needs to pass comprehensive privacy protections. At the very least, we need to be able to sue companies when these sorts of breaches happen (and while we’re at it, it’d be nice if we got more than $5.21 checks in the mail). EFF has long advocated for a strong federal privacy law that includes a private right of action.

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