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We broke 92% of SHA-256 – you should start to migrate from it

stateofutopia.com

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Re: We broke 92% of SHA-256 – you should start to migrate from it

#31

Post by thadt »

Freak_NL wrote: post #8
logicallee wrote: post #2

In the linked work, we've broken 92% of SHA-256 across its full 64 rounds, and were encouraged to publish it by the leading cryptographer in the field (who held the previous record). Currently, SHA-256 is the basis of TLS certificates, bitcoin, and many other security applications. We think it is time to begin to migrate to other hash families, because we expect the rest of SHA-256 to fall soon.

Why omit the name of the leading cryptographer in the field?

They specifically call out Yingxin Li[1] in the acknowledgements section of the paper?

[1] https://eprint.iacr.org/2024/349

Re: We broke 92% of SHA-256 – you should start to migrate from it

#32

Post by hagbard_c »

vl wrote: post #10
logicallee wrote: post #2

In the linked work, we've broken 92% of SHA-256 across its full 64 rounds, and were encouraged to publish it by the leading cryptographer in the field (who held the previous record). Currently, SHA-256 is the basis of TLS certificates, bitcoin, and many other security applications. We think it is time to begin to migrate to other hash families, because we expect the rest of SHA-256 to fall soon.

What does it mean to “break broken 92% of SHA-256“?

As long as there is no verification of the results and their relevancy in reaching higher numbers it means as much as nearly having won the lottery by guessing 9 of the 12 numbers correctly: you did not win the lottery.

Re: We broke 92% of SHA-256 – you should start to migrate from it

#33

Post by dylan604 »

MostlyStable wrote: post #29

I know people (especially around here) hate it when people just post AI output, and I generally agree, since it is trivial for anyone else who is interested to do the same thing. However, the majority of the comments here are from people seemingly asking the author (or someone else) to explain how significant this is, without having taken that step themselves. So while I normally wouldn't do this, in this case it see…

Does the fact that Claude wrote the paper help Claude to think the paper was interesting? I'd suggest sticking to your "I don't normally do this" idea

Re: We broke 92% of SHA-256 – you should start to migrate from it

#36

Post by kstrauser »

logicallee wrote: post #35
mkeeter wrote: post #13

The "Intermediate Report" [1] lists the authors as "Robert V. and Claude (Anthropic)". Is there any reason to believe this is not AI hallucinations? [1] https://stateofutopia.com/papers/2/intermediate-report.pdf

[flagged]

> You can use literally any MD5 tool

> Our certificates implement the full SHA-256 algorithm

We knew MD5 is broken. Do you have a POC for breaking SHA-256, too?

Re: We broke 92% of SHA-256 – you should start to migrate from it

#37

Post by kstrauser »

MostlyStable wrote: post #29

I know people (especially around here) hate it when people just post AI output, and I generally agree, since it is trivial for anyone else who is interested to do the same thing. However, the majority of the comments here are from people seemingly asking the author (or someone else) to explain how significant this is, without having taken that step themselves. So while I normally wouldn't do this, in this case it see…

That's not how this works, though. I don't care if the method is interesting. I care if it works. I can write an interesting proof that P=NP but that doesn't make it valid.

It's on the author to explain what they mean. Here, they haven't.

Re: We broke 92% of SHA-256 – you should start to migrate from it

#38

Post by logicallee »

pavel_lishin wrote: post #7

> Secure hash functions are used to make a short version of a large file. Ideally, it has several properties including making it infeasible to find two files with the same cryptographic hash. We've just gotten 92% of the way there. This has security ramifications in that other researchers are expected to be able to complete the work through similar methods as explored in the paper. We weren't sure if this was a remar…

Thank you for pointing out that that section could be clearer. I've now updated it. It now reads:

>We've just gotten 92% of the way to finding a single collision (this means that there is no full collision yet.). This has security ramifications in that other researchers are expected to be able to complete the work through similar methods as explored in the paper, and eventually produce collisions at will. We weren't sure if this was a remarkable result, since it's not a full collision, but we shared the work with the leading cryptographer in the field, who holds the world records in reduced-round attacks, and got great encouragement to proceed to publish it as a paper, so we did so.

(if we had found a single full collision, we would have just written "we broke SHA-256". This is 92% of the way to a full collision. Any collision is considered a great reduction in the security of the hash, because it means that there two different files with the same cryptographic hash. This is what happened to other algorithms such as MD5, as demonstrated in the linked tool.)

Re: We broke 92% of SHA-256 – you should start to migrate from it

#39

Post by Retr0id »

logicallee wrote: post #2

In the linked work, we've broken 92% of SHA-256 across its full 64 rounds, and were encouraged to publish it by the leading cryptographer in the field (who held the previous record). Currently, SHA-256 is the basis of TLS certificates, bitcoin, and many other security applications. We think it is time to begin to migrate to other hash families, because we expect the rest of SHA-256 to fall soon.

I believe I hold the actual record for most colliding bits in full-round SHA256 (72% of bits matching). My proof fits in a tweet, why doesn't yours?

https://news.ycombinator.com/item?id=38668893

(Also my work does not demonstrate any weakness in SHA256, it's just an application of the birthday paradox)

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