Tag Archives: identification

Surveillance through Push Notifications

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2024/03/surveillance-through-push-notifications.html

The Washington Post is reporting on the FBI’s increasing use of push notification data—”push tokens”—to identify people. The police can request this data from companies like Apple and Google without a warrant.

The investigative technique goes back years. Court orders that were issued in 2019 to Apple and Google demanded that the companies hand over information on accounts identified by push tokens linked to alleged supporters of the Islamic State terrorist group.

But the practice was not widely understood until December, when Sen. Ron Wyden (D-Ore.), in a letter to Attorney General Merrick Garland, said an investigation had revealed that the Justice Department had prohibited Apple and Google from discussing the technique.


Unlike normal app notifications, push alerts, as their name suggests, have the power to jolt a phone awake—a feature that makes them useful for the urgent pings of everyday use. Many apps offer push-alert functionality because it gives users a fast, battery-saving way to stay updated, and few users think twice before turning them on.

But to send that notification, Apple and Google require the apps to first create a token that tells the company how to find a user’s device. Those tokens are then saved on Apple’s and Google’s servers, out of the users’ reach.

The article discusses their use by the FBI, primarily in child sexual abuse cases. But we all know how the story goes:

“This is how any new surveillance method starts out: The government says we’re only going to use this in the most extreme cases, to stop terrorists and child predators, and everyone can get behind that,” said Cooper Quintin, a technologist at the advocacy group Electronic Frontier Foundation.

“But these things always end up rolling downhill. Maybe a state attorney general one day decides, hey, maybe I can use this to catch people having an abortion,” Quintin added. “Even if you trust the U.S. right now to use this, you might not trust a new administration to use it in a way you deem ethical.”

Facial Recognition Systems in the US

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2024/01/facial-recognition-systems-in-the-us.html

A helpful summary of which US retail stores are using facial recognition, thinking about using it, or currently not planning on using it. (This, of course, can all change without notice.)

Three years ago, I wrote that campaigns to ban facial recognition are too narrow. The problem here is identification, correlation, and then discrimination. There’s no difference whether the identification technology is facial recognition, the MAC address of our phones, gait recognition, license plate recognition, or anything else. Facial recognition is just the easiest technology right now.

Breaking Laptop Fingerprint Sensors

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2023/11/breaking-laptop-fingerprint-sensors.html

They’re not that good:

Security researchers Jesse D’Aguanno and Timo Teräs write that, with varying degrees of reverse-engineering and using some external hardware, they were able to fool the Goodix fingerprint sensor in a Dell Inspiron 15, the Synaptic sensor in a Lenovo ThinkPad T14, and the ELAN sensor in one of Microsoft’s own Surface Pro Type Covers. These are just three laptop models from the wide universe of PCs, but one of these three companies usually does make the fingerprint sensor in every laptop we’ve reviewed in the last few years. It’s likely that most Windows PCs with fingerprint readers will be vulnerable to similar exploits.


On Technologies for Automatic Facial Recognition

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2023/09/on-technologies-for-automatic-facial-recognition.html

Interesting article on technologies that will automatically identify people:

With technology like that on Mr. Leyvand’s head, Facebook could prevent users from ever forgetting a colleague’s name, give a reminder at a cocktail party that an acquaintance had kids to ask about or help find someone at a crowded conference. However, six years later, the company now known as Meta has not released a version of that product and Mr. Leyvand has departed for Apple to work on its Vision Pro augmented reality glasses.

The technology is here. Maybe the implementation is still dorky, but that will change. The social implications will be enormous.

The Inability to Simultaneously Verify Sentience, Location, and Identity

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2023/08/the-inability-to-simultaneously-verify-sentience-location-and-identity.html

Really interesting “systematization of knowledge” paper:

“SoK: The Ghost Trilemma”

Abstract: Trolls, bots, and sybils distort online discourse and compromise the security of networked platforms. User identity is central to the vectors of attack and manipulation employed in these contexts. However it has long seemed that, try as it might, the security community has been unable to stem the rising tide of such problems. We posit the Ghost Trilemma, that there are three key properties of identity—sentience, location, and uniqueness—that cannot be simultaneously verified in a fully-decentralized setting. Many fully-decentralized systems—whether for communication or social coordination—grapple with this trilemma in some way, perhaps unknowingly. In this Systematization of Knowledge (SoK) paper, we examine the design space, use cases, problems with prior approaches, and possible paths forward. We sketch a proof of this trilemma and outline options for practical, incrementally deployable schemes to achieve an acceptable tradeoff of trust in centralized trust anchors, decentralized operation, and an ability to withstand a range of attacks, while protecting user privacy.

I think this conceptualization makes sense, and explains a lot.

Experian Privacy Vulnerability

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2023/01/experian-privacy-vulnerability.html

Brian Krebs is reporting on a vulnerability in Experian’s website:

Identity thieves have been exploiting a glaring security weakness in the website of Experian, one of the big three consumer credit reporting bureaus. Normally, Experian requires that those seeking a copy of their credit report successfully answer several multiple choice questions about their financial history. But until the end of 2022, Experian’s website allowed anyone to bypass these questions and go straight to the consumer’s report. All that was needed was the person’s name, address, birthday and Social Security number.

Apple’s Device Analytics Can Identify iCloud Users

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2022/11/apples-device-analytics-can-identify-icloud-users.html

Researchers claim that supposedly anonymous device analytics information can identify users:

On Twitter, security researchers Tommy Mysk and Talal Haj Bakry have found that Apple’s device analytics data includes an iCloud account and can be linked directly to a specific user, including their name, date of birth, email, and associated information stored on iCloud.

Apple has long claimed otherwise:

On Apple’s device analytics and privacy legal page, the company says no information collected from a device for analytics purposes is traceable back to a specific user. “iPhone Analytics may include details about hardware and operating system specifications, performance statistics, and data about how you use your devices and applications. None of the collected information identifies you personally,” the company claims.

Apple was just sued for tracking iOS users without their consent, even when they explicitly opt out of tracking.

Tracking People via Bluetooth on Their Phones

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2022/06/tracking-people-via-bluetooth-on-their-phones.html

We’ve always known that phones—and the people carrying them—can be uniquely identified from their Bluetooth signatures, and that we need security techniques to prevent that. This new research shows that that’s not enough.

Computer scientists at the University of California San Diego proved in a study published May 24 that minute imperfections in phones caused during manufacturing create a unique Bluetooth beacon, one that establishes a digital signature or fingerprint distinct from any other device. Though phones’ Bluetooth uses cryptographic technology that limits trackability, using a radio receiver, these distortions in the Bluetooth signal can be discerned to track individual devices.


The study’s scientists conducted tests to show whether multiple phones being in one place could disrupt their ability to track individual signals. Results in an initial experiment showed they managed to discern individual signals for 40% of 162 devices in public. Another, scaled-up experiment showed they could discern 47% of 647 devices in a public hallway across two days.

The tracking range depends on device and the environment, and it could be several hundred feet, but in a crowded location it might only be 10 or so feet. Scientists were able to follow a volunteer’s signal as they went to and from their house. Certain environmental factors can disrupt a Bluetooth signal, including changes in environment temperature, and some devices send signals with more power and range than others.

One might say “well, I’ll just keep Bluetooth turned off when not in use,” but the researchers said they found that some devices, especially iPhones, don’t actually turn off Bluetooth unless a user goes directly into settings to turn off the signal. Most people might not even realize their Bluetooth is being constantly emitted by many smart devices.

Using Pupil Reflection in Smartphone Camera Selfies

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2022/05/using-pupil-reflection-in-smartphone-camera-selfies.html

Researchers are using the reflection of the smartphone in the pupils of faces taken as selfies to infer information about how the phone is being used:

For now, the research is focusing on six different ways a user can hold a device like a smartphone: with both hands, just the left, or just the right in portrait mode, and the same options in horizontal mode.

It’s not a lot of information, but it’s a start. (It’ll be a while before we can reproduce these results from Blade Runner.)

Research paper.

I Am Not Satoshi Nakamoto

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2021/09/i-am-not-satoshi-nakamoto.html

This isn’t the first time I’ve received an e-mail like this:

Hey! I’ve done my research and looked at a lot of facts and old forgotten archives. I know that you are Satoshi, I do not want to tell anyone about this. I just wanted to say that you created weapons of mass destruction where niches remained poor and the rich got richer! When bitcoin first appeared, I was small, and alas, my family lost everything on this, you won’t find an apple in the winter garden, people only need strength and money. Sorry for the English, I am from Russia, I can write with errors. You are an amazingly intelligent person, very intelligent, but the road to hell is paved with good intentions. Once I dreamed of a better life for myself and my children, but this will never come …

I like the bit about “old forgotten archives,” by which I assume he’s referring to the sci.crypt Usenet group and the Cypherpunks mailing list. (I posted to the latter a lot, and the former rarely.)

For the record, I am not Satoshi Nakamoto. I suppose I could have invented the bitcoin protocols, but I wouldn’t have done it in secret. I would have drafted a paper, showed it to a lot of smart people, and improved it based on their comments. And then I would have published it under my own name. Maybe I would have realized how dumb the whole idea is. I doubt I would have predicted that it would become so popular and contribute materially to global climate change. In any case, I did nothing of the sort.

Read the paper. It doesn’t even sound like me.

Of course, this will convince no one who doesn’t already believe. Such is the nature of conspiracy theories.

Identifying Computer-Generated Faces

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2021/09/identifying-computer-generated-faces.html

It’s the eyes:

The researchers note that in many cases, users can simply zoom in on the eyes of a person they suspect may not be real to spot the pupil irregularities. They also note that it would not be difficult to write software to spot such errors and for social media sites to use it to remove such content. Unfortunately, they also note that now that such irregularities have been identified, the people creating the fake pictures can simply add a feature to ensure the roundness of pupils.

And the arms race continues….

Research paper.

Identifying People by Their Browsing Histories

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2020/08/identifying_peo_9.html

Interesting paper: “Replication: Why We Still Can’t Browse in Peace: On the Uniqueness and Reidentifiability of Web Browsing Histories“:

We examine the threat to individuals’ privacy based on the feasibility of reidentifying users through distinctive profiles of their browsing history visible to websites and third parties. This work replicates and extends the 2012 paper Why Johnny Can’t Browse in Peace: On the Uniqueness of Web Browsing History Patterns[48]. The original work demonstrated that browsing profiles are highly distinctive and stable.We reproduce those results and extend the original work to detail the privacy risk posed by the aggregation of browsing histories. Our dataset consists of two weeks of browsing data from ~52,000 Firefox users. Our work replicates the original paper’s core findings by identifying 48,919 distinct browsing profiles, of which 99% are unique. High uniqueness hold seven when histories are truncated to just 100 top sites. Wethen find that for users who visited 50 or more distinct do-mains in the two-week data collection period, ~50% can be reidentified using the top 10k sites. Reidentifiability rose to over 80% for users that browsed 150 or more distinct domains.Finally, we observe numerous third parties pervasive enough to gather web histories sufficient to leverage browsing history as an identifier.

One of the authors of the original study comments on the replication.