Using Wi-Fi Signals to Identify People by Body Shape

Another paper on using Wi-Fi for surveillance. This one is on identifying people by their body shape. "FreeSense:Indoor Human Identification with WiFi Signals":

Abstract: Human identification plays an important role in human-computer interaction. There have been numerous methods proposed for human identification (e.g., face recognition, gait recognition, fingerprint identification, etc.). While these methods could be very useful under different conditions, they also suffer from certain shortcomings (e.g., user privacy, sensing coverage range). In this paper, we propose a novel approach for human identification, which leverages WIFI signals to enable non-intrusive human identification in domestic environments. It is based on the observation that each person has specific influence patterns to the surrounding WIFI signal while moving indoors, regarding their body shape characteristics and motion patterns. The influence can be captured by the Channel State Information (CSI) time series of WIFI. Specifically, a combination of Principal Component Analysis (PCA), Discrete Wavelet Transform (DWT) and Dynamic Time Warping (DTW) techniques is used for CSI waveform-based human identification. We implemented the system in a 6m*5m smart home environment and recruited 9 users for data collection and evaluation. Experimental results indicate that the identification accuracy is about 88.9% to 94.5% when the candidate user set changes from 6 to 2, showing that the proposed human identification method is effective in domestic environments.

Posted on August 30, 2016 at 12:57 PM14 Comments

Keystroke Recognition from Wi-Fi Distortion

This is interesting research: "Keystroke Recognition Using WiFi Signals." Basically, the user's hand positions as they type distorts the Wi-Fi signal in predictable ways.

Abstract: Keystroke privacy is critical for ensuring the security of computer systems and the privacy of human users as what being typed could be passwords or privacy sensitive information. In this paper, we show for the first time that WiFi signals can also be exploited to recognize keystrokes. The intuition is that while typing a certain key, the hands and fingers of a user move in a unique formation and direction and thus generate a unique pattern in the time-series of Channel State Information (CSI) values, which we call CSI-waveform for that key. In this paper, we propose a WiFi signal based keystroke recognition system called WiKey. WiKey consists of two Commercial Off-The-Shelf (COTS) WiFi devices, a sender (such as a router) and a receiver (such as a laptop). The sender continuously emits signals and the receiver continuously receives signals. When a human subject types on a keyboard, WiKey recognizes the typed keys based on how the CSI values at the WiFi signal receiver end. We implemented the WiKey system using a TP-Link TL-WR1043ND WiFi router and a Lenovo X200 laptop. WiKey achieves more than 97.5% detection rate for detecting the keystroke and 96.4% recognition accuracy for classifying single keys. In real-world experiments, WiKey can recognize keystrokes in a continuously typed sentence with an accuracy of 93.5%.

News article.

Posted on August 30, 2016 at 6:04 AM18 Comments

iPhone Zero-Day Used by UAE Government

Last week, Apple issued a critical security patch for the iPhone: iOS 9.3.5. The incredible story is that this patch is the result of investigative work by Citizen Lab, which uncovered a zero-day exploit being used by the UAE government against a human rights defender. The UAE spyware was provided by the Israeli cyberweapons arms manufacturer NSO Group.

This is a big deal. iOS vulnerabilities are expensive, and can sell for over $1M. That we can find one used in the wild and patch it, rendering it valueless, is a major win and puts a huge dent in the vulnerabilities market. The more we can do this, the less valuable these zero-days will be to both criminals and governments -- and to criminal governments.

Citizen Lab blog post and report. New York Times article. More news articles.

Posted on August 29, 2016 at 1:21 PM39 Comments

Apple Patents Collecting Biometric Information Based on Unauthorized Device Use

Apple received a patent earlier this year on collecting biometric information of an unauthorized device user. The obvious application is taking a copy of the fingerprint and photo of someone using as stolen smartphone.

Note that I have no opinion on whether this is a patentable idea or the patent is valid.

Posted on August 29, 2016 at 6:27 AM27 Comments

Friday Squid Blogging: Self-Repairing Fabrics Based on Squid Teeth

Really:

As shown in the video below, researchers at Pennsylvania State University recently developed a polyelectrolyte liquid solution made of bacteria and yeast that automatically mends clothes.

It doesn't have a name yet, but it's almost miraculous. Simply douse two halves of a ripped fabric in the stuff, hold them together under warm water for about 60 seconds, and the fabric closes the gaps and clings together once more. Having a bit of extra fabric on hand does seem to help, as the video mainly focuses on patching holes rather than re-knitting two halves of a torn piece.

The team got the idea by observing how proteins in squid teeth and human hair are able to self-replicate. Then, they recreated the process using more readily available materials. Best of all, it works with almost all natural fabrics.

As usual, you can also use this squid post to talk about the security stories in the news that I haven't covered.

Posted on August 26, 2016 at 4:30 PM171 Comments

Collision Attacks Against 64-Bit Block Ciphers

We've long known that 64 bits is too small for a block cipher these days. That's why new block ciphers like AES have 128-bit, or larger, block sizes. The insecurity of the smaller block is nicely illustrated by a new attack called "Sweet32." It exploits the ability to find block collisions in Internet protocols to decrypt some traffic, even through the attackers never learn the key.

Paper here. Matthew Green has a nice explanation of the attack. And some news articles. Hacker News thread.

Posted on August 26, 2016 at 2:19 PM30 Comments

The NSA Is Hoarding Vulnerabilities

The National Security Agency is lying to us. We know that because of data stolen from an NSA server was dumped on the Internet. The agency is hoarding information about security vulnerabilities in the products you use, because it wants to use it to hack others' computers. Those vulnerabilities aren't being reported, and aren't getting fixed, making your computers and networks unsafe.

On August 13, a group calling itself the Shadow Brokers released 300 megabytes of NSA cyberweapon code on the Internet. Near as we experts can tell, the NSA network itself wasn't hacked; what probably happened was that a "staging server" for NSA cyberweapons -- that is, a server the NSA was making use of to mask its surveillance activities -- was hacked in 2013.

The NSA inadvertently resecured itself in what was coincidentally the early weeks of the Snowden document release. The people behind the link used casual hacker lingo, and made a weird, implausible proposal involving holding a bitcoin auction for the rest of the data: "!!! Attention government sponsors of cyber warfare and those who profit from it !!!! How much you pay for enemies cyber weapons?"

Still, most people believe the hack was the work of the Russian government and the data release some sort of political message. Perhaps it was a warning that if the US government exposes the Russians as being behind the hack of the Democratic National Committee -- or other high-profile data breaches -- the Russians will expose NSA exploits in turn.

But what I want to talk about is the data. The sophisticated cyberweapons in the data dump include vulnerabilities and "exploit code" that can be deployed against common Internet security systems. Products targeted include those made by Cisco, Fortinet, TOPSEC, Watchguard, and Juniper -- systems that are used by both private and government organizations around the world. Some of these vulnerabilities have been independently discovered and fixed since 2013, and some had remained unknown until now.

All of them are examples of the NSA -- despite what it and other representatives of the US government say -- prioritizing its ability to conduct surveillance over our security. Here's one example. Security researcher Mustafa al-Bassam found an attack tool codenamed BENIGHCERTAIN that tricks certain Cisco firewalls into exposing some of their memory, including their authentication passwords. Those passwords can then be used to decrypt virtual private network, or VPN, traffic, completely bypassing the firewalls' security. Cisco hasn't sold these firewalls since 2009, but they're still in use today.

Vulnerabilities like that one could have, and should have, been fixed years ago. And they would have been, if the NSA had made good on its word to alert American companies and organizations when it had identified security holes.

Over the past few years, different parts of the US government have repeatedly assured us that the NSA does not hoard "zero days" ­ the term used by security experts for vulnerabilities unknown to software vendors. After we learned from the Snowden documents that the NSA purchases zero-day vulnerabilities from cyberweapons arms manufacturers, the Obama administration announced, in early 2014, that the NSA must disclose flaws in common software so they can be patched (unless there is "a clear national security or law enforcement" use).

Later that year, National Security Council cybersecurity coordinator and special adviser to the president on cybersecurity issues Michael Daniel insisted that US doesn't stockpile zero-days (except for the same narrow exemption). An official statement from the White House in 2014 said the same thing.

The Shadow Brokers data shows this is not true. The NSA hoards vulnerabilities.

Hoarding zero-day vulnerabilities is a bad idea. It means that we're all less secure. When Edward Snowden exposed many of the NSA's surveillance programs, there was considerable discussion about what the agency does with vulnerabilities in common software products that it finds. Inside the US government, the system of figuring out what to do with individual vulnerabilities is called the Vulnerabilities Equities Process (VEP). It's an inter-agency process, and it's complicated.

There is a fundamental tension between attack and defense. The NSA can keep the vulnerability secret and use it to attack other networks. In such a case, we are all at risk of someone else finding and using the same vulnerability. Alternatively, the NSA can disclose the vulnerability to the product vendor and see it gets fixed. In this case, we are all secure against whoever might be using the vulnerability, but the NSA can't use it to attack other systems.

There are probably some overly pedantic word games going on. Last year, the NSA said that it discloses 91 percent of the vulnerabilities it finds. Leaving aside the question of whether that remaining 9 percent represents 1, 10, or 1,000 vulnerabilities, there's the bigger question of what qualifies in the NSA's eyes as a "vulnerability."

Not all vulnerabilities can be turned into exploit code. The NSA loses no attack capabilities by disclosing the vulnerabilities it can't use, and doing so gets its numbers up; it's good PR. The vulnerabilities we care about are the ones in the Shadow Brokers data dump. We care about them because those are the ones whose existence leaves us all vulnerable.

Because everyone uses the same software, hardware, and networking protocols, there is no way to simultaneously secure our systems while attacking their systems ­ whoever "they" are. Either everyone is more secure, or everyone is more vulnerable.

Pretty much uniformly, security experts believe we ought to disclose and fix vulnerabilities. And the NSA continues to say things that appear to reflect that view, too. Recently, the NSA told everyone that it doesn't rely on zero days -- very much, anyway.

Earlier this year at a security conference, Rob Joyce, the head of the NSA's Tailored Access Operations (TAO) organization -- basically the country's chief hacker -- gave a rare public talk, in which he said that credential stealing is a more fruitful method of attack than are zero days: "A lot of people think that nation states are running their operations on zero days, but it's not that common. For big corporate networks, persistence and focus will get you in without a zero day; there are so many more vectors that are easier, less risky, and more productive."

The distinction he's referring to is the one between exploiting a technical hole in software and waiting for a human being to, say, get sloppy with a password.

A phrase you often hear in any discussion of the Vulnerabilities Equities Process is NOBUS, which stands for "nobody but us." Basically, when the NSA finds a vulnerability, it tries to figure out if it is unique in its ability to find it, or whether someone else could find it, too. If it believes no one else will find the problem, it may decline to make it public. It's an evaluation prone to both hubris and optimism, and many security experts have cast doubt on the very notion that there is some unique American ability to conduct vulnerability research.

The vulnerabilities in the Shadow Brokers data dump are definitely not NOBUS-level. They are run-of-the-mill vulnerabilities that anyone -- another government, cybercriminals, amateur hackers -- could discover, as evidenced by the fact that many of them were discovered between 2013, when the data was stolen, and this summer, when it was published. They are vulnerabilities in common systems used by people and companies all over the world.

So what are all these vulnerabilities doing in a secret stash of NSA code that was stolen in 2013? Assuming the Russians were the ones who did the stealing, how many US companies did they hack with these vulnerabilities? This is what the Vulnerabilities Equities Process is designed to prevent, and it has clearly failed.

If there are any vulnerabilities that -- according to the standards established by the White House and the NSA -- should have been disclosed and fixed, it's these. That they have not been during the three-plus years that the NSA knew about and exploited them -- despite Joyce's insistence that they're not very important -- demonstrates that the Vulnerable Equities Process is badly broken.

We need to fix this. This is exactly the sort of thing a congressional investigation is for. This whole process needs a lot more transparency, oversight, and accountability. It needs guiding principles that prioritize security over surveillance. A good place to start are the recommendations by Ari Schwartz and Rob Knake in their report: these include a clearly defined and more public process, more oversight by Congress and other independent bodies, and a strong bias toward fixing vulnerabilities instead of exploiting them.

And as long as I'm dreaming, we really need to separate our nation's intelligence-gathering mission from our computer security mission: we should break up the NSA. The agency's mission should be limited to nation state espionage. Individual investigation should be part of the FBI, cyberwar capabilities should be within US Cyber Command, and critical infrastructure defense should be part of DHS's mission.

I doubt we're going to see any congressional investigations this year, but we're going to have to figure this out eventually. In my 2014 book Data and Goliath, I write that "no matter what cybercriminals do, no matter what other countries do, we in the US need to err on the side of security by fixing almost all the vulnerabilities we find..." Our nation's cybersecurity is just too important to let the NSA sacrifice it in order to gain a fleeting advantage over a foreign adversary.

This essay previously appeared on Vox.com.

EDITED TO ADD (8/27): The vulnerabilities were seen in the wild within 24 hours, demonstrating how important they were to disclose and patch.

James Bamford thinks this is the work of an insider. I disagree, but he's right that the TAO catalog was not a Snowden document.

People are looking at the quality of the code. It's not that good.

Posted on August 26, 2016 at 5:56 AM86 Comments

Confusing Security Risks with Moral Judgments

Interesting research that shows we exaggerate the risks of something when we find it morally objectionable.

From an article about and interview with the researchers:

To get at this question experimentally, Thomas and her collaborators created a series of vignettes in which a parent left a child unattended for some period of time, and participants indicated the risk of harm to the child during that period. For example, in one vignette, a 10-month-old was left alone for 15 minutes, asleep in the car in a cool, underground parking garage. In another vignette, an 8-year-old was left for an hour at a Starbucks, one block away from her parent's location.

To experimentally manipulate participants' moral attitude toward the parent, the experimenters varied the reason the child was left unattended across a set of six experiments with over 1,300 online participants. In some cases, the child was left alone unintentionally (for example, in one case, a mother is hit by a car and knocked unconscious after buckling her child into her car seat, thereby leaving the child unattended in the car seat). In other cases, the child was left unattended so the parent could go to work, do some volunteering, relax or meet a lover.

Not surprisingly, the parent's reason for leaving a child unattended affected participants' judgments of whether the parent had done something immoral: Ratings were over 3 on a 10-point scale even when the child was left unattended unintentionally, but they skyrocketed to nearly 8 when the parent left to meet a lover. Ratings for the other cases fell in between.

The more surprising result was that perceptions of risk followed precisely the same pattern. Although the details of the cases were otherwise the same -­ that is, the age of the child, the duration and location of the unattended period, and so on -­ participants thought children were in significantly greater danger when the parent left to meet a lover than when the child was left alone unintentionally. The ratings for the other cases, once again, fell in between. In other words, participants' factual judgments of how much danger the child was in while the parent was away varied according to the extent of their moral outrage concerning the parent's reason for leaving.

Posted on August 25, 2016 at 11:12 AM45 Comments

Interesting Internet-Based Investigative Techniques

In this article, detailing the Australian and then worldwide investigation of a particularly heinous child-abuse ring, there are a lot of details of the pedophile security practices and the police investigative techniques. The abusers had a detailed manual on how to scrub metadata and avoid detection, but not everyone was perfect. The police used information from a single camera to narrow down the suspects. They also tracked a particular phrase one person used to find him.

This story shows an increasing sophistication of the police using small technical clues combined with standard detective work to investigate crimes on the Internet. A highly painful read, but interesting nonetheless.

Posted on August 24, 2016 at 9:30 AM29 Comments

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