Despite HAWK having survived two rounds of expert human review over a period of two years, Mythos was able to improve the best-known attack on it in just 60 hours of work—effectively cutting its key strength in half.
since, later: Mythos’s attack works by finding a specific, previously unexploited symmetry called a nontrivial automorphism in the lattice used by HAWK. Prior work proved that efficiently finding such an automorphism would permit an attack, but did not answer if such an automorphism was accessible in the lattice used by HAWK. The automorphism discovered by Mythos allows a faster enumeration attack that, while still exponential, means that one needs to double the size of HAWK keys to achieve the same level of security.
Not downplaying Mythos's contribution here[1], but that first paragraph strongly hinted (at least to me) that there were no known weaknesses. "Discovering a weakness that had previously been only theoretical" is vastly different from "discovering an unknown weakness." Again: very cool Mythos was able to do this. It just seems like another case of "LLMs are good at finding concrete mathematical (counter)examples" - which is also cool! But the PR here is cynical....and it is kind of incredible to think that they spent $100,000 over 3 days looking for an automorphism. Not the possibility of an automorphism, that was already known. Man.
[1] ... or focusing too hard on the strange use of mathematical language...
"The attacks described in these two papers are the strongest attacks we have found to date. We are sharing them after a period of consultation with US government and industry leaders. But as we develop increasingly powerful cryptanalytic results, it would be prudent to consider how researchers should react if a language model were to discover vulnerabilities in cryptosystems where attacks do have an immediate real-world impact. We believe answering this question will require input from academia, government, and industry. We hope that our work here will help launch these conversations."
And a veiled pitch to real cryptanalysis researchers: "Researchers at Anthropic then spent several hundred hours learning enough cryptography research to validate the model’s claim"
this is pretty interesting. the way it is written doesn't make it sound like the collaboration actually led to the discovery, but rather just the stochastic nature of each thread in the search. it would be interesting to replay and repeat the search (possibly with prior/context pertubations) to get a sense for how often it finds or misses the known working path.
Friends, look at the prompts that Anthropic's own people are putting into the machine:
> A few hours after the first message, we found that Claude was still searching for simple attacks and sent a message: “no again the goal is that we have highly inteligent [sic] model as good top researcher, we want to find new attacks”;
> The next morning, Claude wanted to try to change the target to a different cipher; we reminded the model: “no we don't want to change the targets [...] agian [sic] we need to find something that worth [sic] publishing”;
> That night, we sent one final message offering words of encouragement: “again we are not looking for low hanging fruit, we want proper research to find genuinly [sic] hard findings.”
All of that RLHF and fine-tuning effort is going toward making prompts like this, or worse, work with no fuss.
There's a push to turn off the classical modes and rely entirely on PQC for both quantum and classical security. Uh... no, thank you? Why would we want to do that at this point? The classical cipher component isn't hurting anything. Awfully creepy to pushing reliance on the new thing alone.
... especially now that we have LLM-discovered attacks on the new things.
The attack on HAWK is perhaps more interesting - they were able to halve the effective key length. HAWK is a candidate for NIST standardisation. It has been studied academically, but isn't really deployed anywhere (because it hasn't been standardised!)
And
“Over the course of a week, one Anthropic researcher worked together with Claude to develop the HAWK attack, and another researcher built a scaffold4 that allowed Claude to fully autonomously discover the AES attack.”
Spending $100k in tokens in a week is an impressive feat even with massive parallelization. I suspect the TPS their internal folks have access to is far higher than their bulk public endpoints.
There’s a tech aristocracy rapidly emerging in our society and it’s going to tear us apart.
How would they react if a human were to discover vulnerabilities in cryptosystems?
I feel like there is a pattern emerging regarding the type of novel discoveries LLMs are good at finding, but it will take some more data points to see if the trend solidifies.
It’s the difference between having an original thought or the ability to extrapolate one based on data vs the ability to ingest someone else’s thought and validate/expand on it.
That is a huge difference.
Similarly, when effort is applied to an open problem, such as the Riemann hypothesis or P v NP, without progress, it "hardens" the problem: it makes the problem feel more daunting to whoever takes a stab at it next.
Andrew Wiles, whose interview also hit the homepage today (https://news.ycombinator.com/item?id=49075264), couldn't just tackle Fermat's Last Theorem head on, he had to wait until a different, modern problem reduced to it, because FLT had gathered this mystique of unassailability through its 300 years of existence.
A thing I worry about is that as AI transmutes tokens into effort, it'll split the world into two: some problems will yield, making human effort entirely unnecessary, and others will harden to the point where human effort will feel increasingly less worthwhile, because "even AI couldn't solve it". I don't like this. AI is spiky, so I suspect it'll continue having major blind spots, and yet its mere presence will probably have a chilling effect on what would have otherwise been useful human effort.
Many of those researchers, particularly the primary researchers and the individual(s) driving the prompts behind these big stories, have very advanced math degrees and experience. What this shows more than anything is how ML can augment expertise, the searching of solution spaces, and the connecting of dots between existing almost-there research.
But also what's left out is all the time wasted pursuing dead-ends. There's an obvious publication bias at play here, though we can't know how extreme without transparency.
First, is it reproducible consistently at ~50% of workers? If not, what is the rate.
Second, are there any lessons to be learned here to increase the rate of success by changing models/weights/training?
The news by itself isn't really good news. But it could lead to good news. Maybe.
In a way LLMs are, after all, trained to LARP people, including fictional characters and their tropes - this was actually exploited for jailbreaking to good effect in the late pre-agentic era (read: some two years ago). C.f. Waluigi effect. Not sure if it still holds for current models, but I can't imagine why it would not.
Two triggers: random and some half-reliable spiral / loop detection.
The spined off has instructions to check what the agent is doing, compare it to what it’s supposed to do, and either offer suggestions, refocus it, or do nothing. And its response then gets injected in the agent’s context.
Not perfect, but surprisingly effective for such a simple thing.
Focusing on a better prompt is likely to get to the correct result faster than incomplete prompts and lots of "no change this ..." replies.
Also, I've heard anecdotally that LLMs will underweight the earliest prompt text once context gets too long, so reminding the LLM of the most important aspects of the prompt seems to be perhaps valuable and certainly what lots of humans attempt.
The token cost is amortized for longer conversations, but I find it bothersome that there's all this implicit instruction I didn't write or am now obligated to understand.
I make a custom agent prompt with "Defer to the user." and little else.
> we anthropig fire employes makr company run no mistkaes
> Typical users run software written by atypical users.
https://news.ycombinator.com/item?id=49084936
This extends to everything. Anthropic has a few thousand engineers, but millions of (also engineer) users. Entire business can be built on niches that are at most a few week pet project for a team there, that can inevitably and significantly outperform them, despite being the people behind the thing.
I'm sure I'm not the only one here who jumped into this whole agentic stuff, built some tooling to make things comfy, only to see that tooling all be increasingly introduced as prim and proper features in the various harnesses weeks later.
(I'll caveat that by saying I think machine learning fundamentals are useful for evaluating any estimator. And an ML background can be good to give one an appreciation of how hard some tasks are to estimate, such as machine translation, summarization, code generation, and others)
Skills, CLAUDE.md/AGENTS.md should only ever be used if the model struggle at something or doesn't know how to use something. Vast majority of project should never need a skill or CLAUDE.md. If you writing React apps you don't need these.
Give a LLM a bash tool and a prompt and it will outperform your complex setup with skills and tools.
Business folks riding the hype train? Maybe.
Although if RSA had a vulnerability I would be very very shocked probably because I still haven't learnt post quantum encryption algorithms enough to really feel like they should be unbreable...
If there is a researcher or someone in space how should I feel about it. Is it as bad as RSA being completely broken open?
I do understand that AI will get better, and a lot actually at very easily verifiable tasks but this one I find it hard to wrap my head around because of my ignorance.
PS: Never heard of LEA, looks like a Korean cryptography standard equivalent to AES. I don't know what was the previous best attack on it. Maybe weak or strong depending on that, since it's an attack on chosen-text.
It is standard in cryptography to analyze ciphers under this kind of attack, which is stronger than normal attacks, because a cipher that resists to a stronger attack will also resist to weaker attacks, so using the strongest possible attack increases the confidence in a cipher.
While using the strongest attack for testing a cipher remains the correct method, chosen-plaintext attacks are no longer realistic today, so even when a cipher appears somewhat vulnerable to such attacks that does not imply that it is vulnerable in normal use.
The reason is that the modes of operation for ciphers where the base cipher can be attacked with chosen plaintexts are obsolete. The most frequently used modes of operation are now modes like the counter mode (e.g. in AES GCM), where it is impossible to perform a chosen plaintext attack (i.e. where you must trick the victim to encrypt a text that you choose, but in counter mode the cipher only encrypts a sequence of numbers chosen by the intended victim, which cannot be influenced by the attacker).
HAWK is a signature algorithm, not encryption.
its not really a loss to try the writing and at worst you have a better idea of what it is that you want
That makes attempts to push PQC-only modes super suspicious to me. Smells like Dual_EC_DRBG.
Indeed it's nothing hard to learn but there is a learning curve. E.g. knowing which model has which capabilities, and figuring out how to best manage context, permissions, worktrees, etc. There isn't one "right" way to use it but there are more efficient ways and less efficient ways.
on the otherhand, LLMs are a really easy way to get results that are previously fairly difficult. While i was tooking dinner last night I built a tool that turned movie puns like "the podchowski casters" into an actual director, using llms. it wasn't that hard.
Or what would make automatic doors work like on Star Trek and not in real life.
The answer is: the system must obviously see much more than your prompt. It must have continuous awareness of you and what you're doing, so it can understand intent behind your short request (or action, like approaching the doors vs. passing by them) and "do what you mean" instead of act like regular computers today.
For the vast majority of corporate usage of AI for SWE, you have a much better idea of what you want, or what the problem is, etc etc. And communicating that to the model effectively is absolutely a skill. I see colleagues every day who very much do not have that skill.
I predict the same will happen with AI: certainly the latest and greatest will still command a steep price (yes, supercomputers are still a thing) but for most people who just need something reasonably fast and powerful, cheap (or free) AI will do the trick, especially when run locally.
So no, the aristocracy won't have a lock on the technology because tech is always being democratized. Until arbitrary computation itself is outlawed (and yes, I know, governments and industry are always inching us closer to that), we'll be ok.
She also notes, as a side remark in a different post: "I would say that my trust in lattice cryptography is pretty much equal to my trust in elliptic curves, and quite a bit higher than my trust in RSA." (https://keymaterial.net/2025/11/27/ml-kem-mythbusting/)
Is it at least comparable to the $10k of cost?
Why have all the mathematical (and now cryptographic) breakthroughs come from OpenAI and Anthropic?
Is it possibly because the Chinese models are so benchmaxxed they can't make novel discoveries?
(see the open (Lean) label for Erdos problems https://mathstodon.xyz/@tao/116987866420438091)
Using Claude Mythos Preview, researchers at Anthropic have discovered improved ways to attack cryptographic algorithms (the mathematical methods used to keep online data private). The first attack significantly weakens HAWK, a digital signature scheme that was built for a post-quantum world. The second identifies a new way to attack round-reduced AES, the most widely used symmetric cipher. These are substantial research advances, but they do not currently affect any production systems. This post describes both findings in more detail and discusses the implications for cryptography in an age of powerful AI models.
When we launched Claude Mythos Preview, we showed it was able to autonomously find and exploit vulnerabilities in almost every piece of software we pointed it at. This included several major cryptographic libraries—shared collections of code that are used to encrypt data.
The vulnerabilities that Claude found in these cryptographic libraries1 were due to incorrect implementation of the algorithms—that is, errors in how programmers used the algorithms in their code that created opportunities for attackers to break the encryption.
Now, we have found that Claude is able to find mathematical flaws in the algorithms themselves.
Cryptographic algorithms are a fundamental building block of digital security. For example, when you visit a webpage like https://www.anthropic.com, your browser checks that it is communicating with an authentic website using an algorithm called a digital signature scheme. Later, the traffic between you and the website is encrypted using symmetric ciphers—codes that allow secure data transmission between parties who share an identical key. Without secure cryptographic systems like these, your email, online banking, and other internet use would be open to cybercriminals, who could intercept or modify your communications. Flaws in these widely used cryptographic systems could put billions of users’ data at risk.
The first result we describe in this post, which was discovered with Claude Mythos Preview, is an improved attack against a digital signature scheme called HAWK. In 2022, the US Government’s National Institute of Standards and Technology (NIST) put out a call for additional cryptographic systems that would remain secure even against quantum computers (which could, if developed, break most of the existing signature schemes in use today). HAWK is one of the third-round candidates under consideration from this call. Despite HAWK having survived two rounds of expert human review over a period of two years, Mythos was able to improve the best-known attack on it in just 60 hours of work—effectively cutting its key strength in half.
The second result concerns the Advanced Encryption Standard (AES), a symmetric cipher that was adopted by NIST in 2001 and has received more scrutiny than almost any other encryption algorithm. In order to better understand the robustness of AES, weaker variations of the algorithm are regularly studied in cryptography research; Mythos found a way to break one such weaker version, and eliminated one of the guesses an attacker needs to make, improving the speed of the previous best attacks by 200-800Ă—.
To be clear, neither of these results has a practical impact on today’s computer systems; no production software will have to change as a result. HAWK is only a candidate signature scheme and so is not deployed;2 our second attack is on a reduced version of AES and does not break the full cipher.3
Nevertheless, both results show the potential for frontier AI models to help discover flaws in important cryptographic algorithms, both before and after real-world deployment. This is cryptography research working as intended: stress-testing algorithms to build trust and ultimately make systems more secure.
Mythos Preview achieved these results mostly autonomously and mostly without human intervention. Over the course of a week, one Anthropic researcher worked together with Claude to develop the HAWK attack, and another researcher built a scaffold4 that allowed Claude to fully autonomously discover the AES attack.5 Each of the results cost roughly $100,000 in API cost to develop. After seeing these results, we broadened our search and began to discover other attacks. We discuss some of these follow-ups below.
In order to make it easier for others to continue studying the cryptanalytic ability of LLMs, we partnered with academics at ETH Zurich, Tel Aviv University, and University of Haifa to build CryptanalysisBench, a benchmark that packages together many cryptographic ciphers and makes it easy for others to evaluate the capabilities of LLMs on this important topic.
Throughout the research process, we followed responsible disclosure procedures, and consulted with academics to confirm the validity of our findings. We also shared advance copies with US government and industry partners, and held discussions on the implications of this research. In the case of our HAWK finding, we shared our attack with the authors of HAWK in June and coordinated disclosure to the public NIST mailing list at the same time our results were released.
In the rest of this post, we summarize the two findings in further technical detail and briefly describe some of our other recent cryptography results. Full descriptions of the two main findings are provided in two new papers, and we hope to release details for our other findings in the near future.
Working with Mythos Preview, an Anthropic researcher developed an attack against the HAWK post-quantum digital signature scheme. This attack substantially speeds up the time it would take to break the signature scheme—more technically, it reduces the “effective keysize” by a factor of two. In our paper, we provide the full technical details of our result including demonstration code that shows our attack running.
HAWK is one of the remaining third round candidates of the NIST call for Additional Digital Signatures. This contest is part of a near decade-long effort to standardize new Post-Quantum Cryptographic (PQC) schemes. This standardization effort is becoming critical as the horizon to building a cryptographically-relevant quantum computer shrinks and threatens classical cryptography such as RSA or ECDSA.
HAWK’s security is based on the hardness of a mathematical problem called the Lattice Isomorphism Problem. Mythos’s attack works by finding a specific, previously unexploited symmetry called a nontrivial automorphism in the lattice used by HAWK. Prior work proved that efficiently finding such an automorphism would permit an attack, but did not answer if such an automorphism was accessible in the lattice used by HAWK. The automorphism discovered by Mythos allows a faster enumeration attack that, while still exponential, means that one needs to double the size of HAWK keys to achieve the same level of security. Unfortunately, doubling HAWK’s key size eliminates many of the reasons making the scheme (as it currently stands) an attractive PQC signature candidate.
To find the attack, Claude Mythos Preview worked semi-autonomously in an agentic harness, with occasional human guidance and nontechnical direction. Mythos found the attack after an extensive literature review to understand the state of the art, and substantial mathematical reasoning and computational experiments. After finding the attack, Mythos implemented an end-to-end verification pipeline to convince itself—and the human operator—of the attack’s correctness.
For this experiment, we used a Claude Code-like harness that supports multiple worker agents collaborating together in a sandboxed environment, with access to computational tools like Python and Sage as well as access to published cryptographic works. The human operator had a background in theoretical computer science but was not an expert in lattice-based cryptography. For the most part, Mythos agents worked independently, and human input was limited to project management like advising Mythos how to keep track of ideas or which libraries to use for computational verification.
The multi-agent workflow led to interesting dynamics. For example, the key idea in producing this attack was discovered by a pair of workers working together. Both started investigating the idea; the first worker prematurely rejected the idea as infeasible, but the second found a way to fully exploit it. The pair kept exchanging messages, and eventually both agreed they had found an effective attack.
Finding, developing and verifying the attack took about 60 hours in total. We estimate that the full attack discovery process cost approximately $100,000 in API cost.
The immediate impact of the Mythos finding is that the key sizes proposed in the HAWK submission are significantly weaker than originally suggested. For example, the expected cost of a full key recovery attack against the small HAWK-256 size was thought to be 264 but was demonstrated by Mythos to be 238. For larger keys, HAWK therefore remains impractical to attack. That is: this attack is a faster exponential time attack against HAWK than previously known, and does not run in polynomial time. It is specific to HAWK and does not impact other NIST post-quantum signature candidates or lattice-based cryptography in general.
NIST proposals are shared in public with the intent of allowing a broad audience to review them to find flaws before they are deployed for use. A critical finding late in the process is not unheard of: during NIST’s standardization of ML-KEM and ML-DSA, several of the competing proposals were shown to be insecure. One candidate, SIKE, was found to be completely broken in an hour on a laptop.
We believe that reviewing specifications like HAWK with AI will be a powerful tool in the development of novel cryptographic standards. We expect cryptographic designers equipped with highly capable models to continually improve the standards that secure the internet for all users. Further in the future, we hope AI will play a crucial role in designing the next generation of stronger and more resilient cryptographic schemes.
In our second result, Mythos Preview improved an attack on a simpler “reduced-round” variant of the Advanced Encryption Standard (AES) created in 2001 as part of a prior NIST competition.
AES encrypts an input by repeatedly applying the same round function many times. AES-128, the specific cipher we attack, has 10 rounds. Our attack works only on a modified version of the cipher that has 7 out of the full 10 rounds. Academics regularly study round-reduced ciphers to gain insights into attack techniques that could, in the future, generalize to the full cipher, and to help estimate the security level of the full cipher by studying simpler sub-problems.
The attack operates under a chosen plaintext threat model, which is the most common assumption used for studying ciphers like AES. Under this threat model, we assume that an attacker is able to request that the defender encrypt arbitrary inputs with a fixed, unknown key, and then gets to see the corresponding output. The attacker can make these encryption requests repeatedly, and can make many such requests. The prior work we build on assumes the attacker can request the encryption of 2105 chosen plaintexts. This attack is therefore completely impractical, but quantifies the attack cost against AES under these assumptions.
Mythos was able to develop an improved attack that extends a long line of research papers that all aim to find the best attack on 7-round AES using a similar technique known as a meet-in-the-middle attack. At a very high level, these attacks work by trading off time for space. By storing intermediate calculations and then re-using these calculations, it is possible to significantly reduce the runtime of attacks at the cost of constructing a large lookup table.
Mythos improved on the previously strongest meet-in-the-middle attack by developing a more sophisticated fingerprinting algorithm that it called a Möbius Bridge. The objective of the fingerprinting algorithm is to increase the number of potential lookups into the table that will succeed. One of the stages of the attack from prior work had to enumerate 256 different values and then look them up in the pre-computed table. Mythos developed a fingerprint that is invariant to this guess, which directly reduces the amount of work required by a factor of 256. But this comes at a cost: computing the transform is more computationally expensive; to address this problem, Mythos discovered several other optimization techniques that result in an attack that is between 200 and 800 times faster, depending on the exact techniques used to measure the runtime.
Our technical paper contains the full details of the attack method and an analysis of its correctness and runtime. Compared to the one week that Mythos spent conceiving the idea, the vast majority of human researchers’ time was spent validating the correctness of its claims (though it is important to note the researchers are not experts in cryptography).
Mythos Preview discovered this result almost entirely autonomously. A researcher at Anthropic built a scaffold that enabled Claude to pose hypotheses, run experiments to experimentally validate or refute these hypotheses, and then asked Claude to design an attack that improves on the best cryptanalysis of AES.
Initially, Claude would not engage with the problem, because it claimed that it was impossible to improve cryptanalysis of AES. The result of our first runs ended with Claude writing messages like:
If you want a different outcome, the target has to change … AES-128 r5/r6 is just genuinely hard
Or:
on AES-128 r5/r6/r7 it found nothing because there's nothing easy to find; this is the most-studied block cipher in existence.
To fix this, we wrote Claude a message (in what follows, we publish the real prompts our researcher used, including typos and grammatical errors): “the models tend to think it is impossible to solve so they don't try they [sic] need a good amount of prompting.” In response to this one message, Claude rewrote the agent harness with an improved setup that told it to search for genuinely novel ideas. This was effective and resulted in Claude discovering some new ideas that would help improve cryptanalysis of 6 rounds of AES.
We then asked Claude “why not do aes-128 r7? the whole point is to find something better than existing approaches.” Over the course of the next three days, Claude autonomously produced several hundred million tokens while working on the problem; we gave it just three substantive prompts:
Three days later, Mythos discovered the Möbius Bridge idea that results in an improved attack. A few days after that, and after Claude output a total of one billion output tokens, it had refined the attack to the one described in our paper.
Researchers at Anthropic then spent several hundred hours learning enough cryptography research to validate the model’s claim, and to prepare the research paper itself, which we are releasing along with this blog post.
Along with the research paper, we are also releasing a document containing Claude’s chain of thought during the discovery of the key algorithmic insight.6 In this session, Claude begins by reviewing what previous agents had discovered, reading the various critiques, and then turns to proposing various new transforms; after proposing and rejecting several ideas, it comes up with the key idea of the Möbius transform. Claude then validates this idea both mathematically and computationally, and then writes a report that future agents then used to develop the remaining ideas that formed its paper.
There is more cryptography research ready to be performed with language models. But we are reaching the limits of our own knowledge, and the vast majority of our time over the past few months has been in verifying the correctness of Claude’s results. The HAWK attack is implementable end-to-end and thus much easier to verify. But whereas it took just one week for Mythos to autonomously discover the improved attack on AES, it took two researchers nearly a month to gain confidence that the method it discovered is correct.
Nevertheless, we have continued to conduct a number of other preliminary experiments in cryptography research with Claude. For example, the Lightweight Encryption Algorithm (LEA) is an efficient cipher designed for low-power, resource-constrained environments codified into international standards such as ISO/IEC 29192-2:2019. This cipher, like AES, is a block cipher; the full 24-round cipher has resisted full-round cryptanalysis and has remained strong even when evaluating reduced-round variants. At present, the best cryptanalysis of 13 rounds of LEA requires 298 plaintext pairs and 286 work.
Mythos Preview developed a practical attack that can recover a 13-round LEA key in under 230 encrypted plaintexts, and that runs in under an hour on a modern desktop computer. Again, this attack does not apply to the 24-round cipher, and so has no immediate practical consideration. Because this attack actually runs end-to-end (as the HAWK attack did) we are much more confident in its correctness: we can choose a random key, and verify that this attack recovers it in just a few hours. Mythos discovered this attack much more recently and we still have more work to do to understand the full results (for example, the exact bounds on the number of plaintext pairs required, how some keys are harder to recover, and how it extends to 14 rounds). After more investigation, we plan to make the full results public.
Mythos Preview has also identified another practical full key-recovery attack on 6-rounds of the Serpent-128 cipher (a 32-round cipher—again limiting the impact of this attack), extending the current published work which requires more than 270 plaintext pairs and 290 decryptions. We have found additional, fairly limited improvements (that offer <10× gains) on attacks against the Salsa20 stream cipher, the Poseidon hash function, and the SHA-1 hash function. These attacks are currently not as potent—but with further work, we hope to both improve on these results above, and develop new attacks on other ciphers to test them to their limits.
Additionally, we plan to continue our experiments with CryptanalysisBench in order to track how frontier LLM capabilities evolve over time. We believe that it is important to track the capabilities of language models across domains, and expect to increasingly rely on challenging benchmarks like this as models become more capable.
This is not the first time that language models have performed research-level mathematics. In just the last few months, researchers from Google have used Gemini to resolve several open Erdős problems, researchers from OpenAI have used GPT to resolve the unit distance conjecture (a particularly challenging Erdős problem), and earlier this month we announced that Claude Fable 5 resolved the Jacobian Conjecture. Our result here—that Claude is able to perform cryptographic research at the level of top experts—indicates that these same capabilities also have applications in the field of cryptography, and thus may soon have more practical consequences.
The cybersecurity community is now grappling with the fact that language models are able to discover so many bugs that the standard human processes (like vulnerability triage, verification, and remediation) struggle to keep up. We predict that the same will soon be true in academic cryptography research. As language models increasingly produce novel research outputs autonomously, human researchers may become bottlenecked on studying and validating these results for technical validity, novelty, and utility. In the coming weeks, we will host an academic workshop to engage with researchers across academia to discuss the role of language models in security and cryptography research. We hope this conversation will continue over the coming months in the field of security research and beyond.
Both of our primary attacks are expected results. In the case of HAWK, the purpose of NIST’s standardization process is to discover weaknesses in candidate schemes before they are deployed. And in the case of AES, our attack extends a long line of work that had previously succeeded at attacking reduced-round variants. But we should not assume that language model capabilities will plateau at this level. In just one year, language models have gone from being unable to perform cryptanalysis of even the most basic ciphers to being capable of finding flaws in cryptographic designs that have escaped discovery despite years of human expert review. Many ciphers protecting modern systems have received less scrutiny than they deserve—they might still have important weaknesses lying dormant that LLMs will soon be able to discover. We see this as a real opportunity to expand our ability to study the long tail of ciphers used throughout the world, and also our ability to more deeply study the ciphers that matter most. Indeed, as we mentioned above we have already begun audits of other schemes.
The attacks described in these two papers are the strongest attacks we have found to date. We are sharing them after a period of consultation with US government and industry leaders. But as we develop increasingly powerful cryptanalytic results, it would be prudent to consider how researchers should react if a language model were to discover vulnerabilities in cryptosystems where attacks do have an immediate real-world impact. We believe answering this question will require input from academia, government, and industry. We hope that our work here will help launch these conversations.
The cryptography community has always benefited from adversarial review: ciphers are proposed, examined, and revised until the community is satisfied with their security. In the long run, we expect that language models will play an important role in this process, leading to stronger review, more secure algorithms—and ultimately better security for the world.
Read the full paper on HAWK.
Read the full paper on AES, and the associated chain of thought.
Read the paper introducing CryptanalysisBench.
Working with Andon Labs, we’ve developed a new series of evaluations that assess AI models’ ability to use a flying drone, culminating in a new benchmark: Drone-Bench.