Remotely Controlling Touchscreens

This is more of a demonstration than a real-world vulnerability, but researchers can use electromagnetic interference to remotely control touchscreens.

From a news article:

It’s important to note that the attack has a few key limitations. Firstly, the hackers need to know the target’s phone passcode, or launch the attack while the phone is unlocked. Secondly, the victim needs to put the phone face down, otherwise the battery and motherboard will block the electromagnetic signal. Thirdly, the antenna array has to be no more than four centimeters (around 1.5 inches) away. For all these reasons the researchers themselves admit that the “invisible finger” technique is a proof of concept that at this point is far from being a threat outside of a university lab.

Posted on August 16, 2022 at 6:59 AM5 Comments

$23 Million YouTube Royalties Scam

Scammers were able to convince YouTube that other peoples’ music was their own. They successfully stole $23 million before they were caught.

No one knows how common this scam is, and how much money total is being stolen in this way. Presumably this is not an uncommon fraud.

While the size of the heist and the breadth of the scheme may be very unique, it’s certainly a situation that many YouTube content creators have faced before. YouTube’s Content ID system, meant to help creators, has been weaponized by bad faith actors in order to make money off content that isn’t theirs. While some false claims are just mistakes caused by automated systems, the MediaMuv case is a perfect example of how fraudsters are also purposefully taking advantage of digital copyright rules.

YouTube attempts to be cautious with who it provides CMS and Content ID tool access because of how powerful these systems are. As a result, independent creators and artists cannot check for these false copyright claims nor do they have the power to directly act on them. They need to go through a digital rights management company that does have access. And it seems like thieves are doing the same, falsifying documents to gain access to these YouTube tools through these third parties that are “trusted” with these tools by YouTube.

Posted on August 15, 2022 at 9:14 AM11 Comments

Twitter Exposes Personal Information for 5.4 Million Accounts

Twitter accidentally exposed the personal information—including phone numbers and email addresses—for 5.4 million accounts. And someone was trying to sell this information.

In January 2022, we received a report through our bug bounty program of a vulnerability in Twitter’s systems. As a result of the vulnerability, if someone submitted an email address or phone number to Twitter’s systems, Twitter’s systems would tell the person what Twitter account the submitted email addresses or phone number was associated with, if any. This bug resulted from an update to our code in June 2021. When we learned about this, we immediately investigated and fixed it. At that time, we had no evidence to suggest someone had taken advantage of the vulnerability.

In July 2022, we learned through a press report that someone had potentially leveraged this and was offering to sell the information they had compiled. After reviewing a sample of the available data for sale, we confirmed that a bad actor had taken advantage of the issue before it was addressed.

This includes anonymous accounts.

This comment has it right:

So after forcing users to enter a phone number to continue using twitter, despite twitter having no need to know the users phone number, they then leak the phone numbers and associated accounts. Great.

But it gets worse… After being told of the leak in January, rather than disclosing the fact millions of users data had been open for anyone who looked, they quietly fixed it and hoped nobody else had found it.

It was only when the press started to notice they finally disclosed the leak.

That isn’t just one bug causing a security leak—it’s a chain of bad decisions and bad security culture, and if anything should attract government fines for lax data security, this is it.

Twitter’s blog post unhelpfully goes on to say:

If you operate a pseudonymous Twitter account, we understand the risks an incident like this can introduce and deeply regret that this happened. To keep your identity as veiled as possible, we recommend not adding a publicly known phone number or email address to your Twitter account.

Three news articles.

Posted on August 12, 2022 at 9:13 AM36 Comments

A Taxonomy of Access Control

My personal definition of a brilliant idea is one that is immediately obvious once it’s explained, but no one has thought of it before. I can’t believe that no one has described this taxonomy of access control before Ittay Eyal laid it out in this paper. The paper is about cryptocurrency wallet design, but the ideas are more general. Ittay points out that a key—or an account, or anything similar—can be in one of four states:

safe Only the user has access,
loss No one has access,
leak Both the user and the adversary have access, or
theft Only the adversary has access.

Once you know these states, you can assign probabilities of transitioning from one state to another (someone hacks your account and locks you out, you forgot your own password, etc.) and then build optimal security and reliability to deal with it. It’s a truly elegant way of conceptualizing the problem.

Posted on August 12, 2022 at 6:38 AM21 Comments

NIST’s Post-Quantum Cryptography Standards

Quantum computing is a completely new paradigm for computers. A quantum computer uses quantum properties such as superposition, which allows a qubit (a quantum bit) to be neither 0 nor 1, but something much more complicated. In theory, such a computer can solve problems too complex for conventional computers.

Current quantum computers are still toy prototypes, and the engineering advances required to build a functionally useful quantum computer are somewhere between a few years away and impossible. Even so, we already know that that such a computer could potentially factor large numbers and compute discrete logs, and break the RSA and Diffie-Hellman public-key algorithms in all of the useful key sizes.

Cryptographers hate being rushed into things, which is why NIST began a competition to create a post-quantum cryptographic standard in 2016. The idea is to standardize on both a public-key encryption and digital signature algorithm that is resistant to quantum computing, well before anyone builds a useful quantum computer.

NIST is an old hand at this competitive process, having previously done this with symmetric algorithms (AES in 2001) and hash functions (SHA-3 in 2015). I participated in both of those competitions, and have likened them to demolition derbies. The idea is that participants put their algorithms into the ring, and then we all spend a few years beating on each other’s submissions. Then, with input from the cryptographic community, NIST crowns a winner. It’s a good process, mostly because NIST is both trusted and trustworthy.

In 2017, NIST received eighty-two post-quantum algorithm submissions from all over the world. Sixty-nine were considered complete enough to be Round 1 candidates. Twenty-six advanced to Round 2 in 2019, and seven (plus another eight alternates) were announced as Round 3 finalists in 2020. NIST was poised to make final algorithm selections in 2022, with a plan to have a draft standard available for public comment in 2023.

Cryptanalysis over the competition was brutal. Twenty-five of the Round 1 algorithms were attacked badly enough to remove them from the competition. Another eight were similarly attacked in Round 2. But here’s the real surprise: there were newly published cryptanalysis results against at least four of the Round 3 finalists just months ago—moments before NIST was to make its final decision.

One of the most popular algorithms, Rainbow, was found to be completely broken. Not that it could theoretically be broken with a quantum computer, but that it can be broken today—with an off-the-shelf laptop in just over two days. Three other finalists, Kyber, Saber, and Dilithium, were weakened with new techniques that will probably work against some of the other algorithms as well. (Fun fact: Those three algorithms were broken by the Center of Encryption and Information Security, part of the Israeli Defense Force. This represents the first time a national intelligence organization has published a cryptanalysis result in the open literature. And they had a lot of trouble publishing, as the authors wanted to remain anonymous.)

That was a close call, but it demonstrated that the process is working properly. Remember, this is a demolition derby. The goal is to surface these cryptanalytic results before standardization, which is exactly what happened. At this writing, NIST has chosen a single algorithm for general encryption and three digital-signature algorithms. It has not chosen a public-key encryption algorithm, and there are still four finalists. Check NIST’s webpage on the project for the latest information.

Ian Cassels, British mathematician and World War II cryptanalyst, once said that “cryptography is a mixture of mathematics and muddle, and without the muddle the mathematics can be used against you.” This mixture is particularly difficult to achieve with public-key algorithms, which rely on the mathematics for their security in a way that symmetric algorithms do not. We got lucky with RSA and related algorithms: their mathematics hinge on the problem of factoring, which turned out to be robustly difficult. Post-quantum algorithms rely on other mathematical disciplines and problems—code-based cryptography, hash-based cryptography, lattice-based cryptography, multivariate cryptography, and so on—whose mathematics are both more complicated and less well-understood. We’re seeing these breaks because those core mathematical problems aren’t nearly as well-studied as factoring is.

The moral is the need for cryptographic agility. It’s not enough to implement a single standard; it’s vital that our systems be able to easily swap in new algorithms when required. We’ve learned the hard way how algorithms can get so entrenched in systems that it can take many years to update them: in the transition from DES to AES, and the transition from MD4 and MD5 to SHA, SHA-1, and then SHA-3.

We need to do better. In the coming years we’ll be facing a double uncertainty. The first is quantum computing. When and if quantum computing becomes a practical reality, we will learn a lot about its strengths and limitations. It took a couple of decades to fully understand von Neumann computer architecture; expect the same learning curve with quantum computing. Our current understanding of quantum computing architecture will change, and that could easily result in new cryptanalytic techniques.

The second uncertainly is in the algorithms themselves. As the new cryptanalytic results demonstrate, we’re still learning a lot about how to turn hard mathematical problems into public-key cryptosystems. We have too much math and an inability to add more muddle, and that results in algorithms that are vulnerable to advances in mathematics. More cryptanalytic results are coming, and more algorithms are going to be broken.

We can’t stop the development of quantum computing. Maybe the engineering challenges will turn out to be impossible, but it’s not the way to bet. In the face of all that uncertainty, agility is the only way to maintain security.

This essay originally appeared in IEEE Security & Privacy.

EDITED TO ADD: One of the four public-key encryption algorithms selected for further research, SIKE, was just broken.

Posted on August 8, 2022 at 6:20 AM42 Comments

Friday Squid Blogging: New Squid Species

Seems like they are being discovered all the time:

In the past, the DEEPEND crew has discovered three new species of Bathyteuthids, a type of squid that lives in depths between 700 and 2,000 meters. The findings were validated and published in 2020. Another new squid species description is currently in review at the Bulletin of Marine Science.

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

Read my blog posting guidelines here.

Posted on August 5, 2022 at 4:13 PM79 Comments

SIKE Broken

SIKE is one of the new algorithms that NIST recently added to the post-quantum cryptography competition.

It was just broken, really badly.

We present an efficient key recovery attack on the Supersingular Isogeny Diffie­-Hellman protocol (SIDH), based on a “glue-and-split” theorem due to Kani. Our attack exploits the existence of a small non-scalar endomorphism on the starting curve, and it also relies on the auxiliary torsion point information that Alice and Bob share during the protocol. Our Magma implementation breaks the instantiation SIKEp434, which aims at security level 1 of the Post-Quantum Cryptography standardization process currently ran by NIST, in about one hour on a single core.

News article.

Posted on August 4, 2022 at 6:56 AM26 Comments

Sidebar photo of Bruce Schneier by Joe MacInnis.