Thread

RSA-896

229 points · 90 comments · madars

Retr0id · 1789904561 · focus · HN ↗
If anyone else has spare GPU hours they don't know what to do with, may I recommend partial hash collisions: <a href="https://github.com/DavidBuchanan314/birthday_party" rel="nofollow">https://github.com/DavidBuchanan314/birthday_party
(The "record" set by me only took about 1 GPU day - easy to beat!)
1. gpugreg · 1789906076 · focus · HN ↗
  Here's a larger partial hash collision (108 trailing bits):
  echo 23ca73454a1b981fe51cad0dbd05f4e696795ba67abb28c61aea1a024e5bbeca | xxd -r -p | sha256sum echo a16a8141361ae9834ad171ec28961fc8a951ff1bfc3a9ce0dc2fcdbdfa2ccd35 | xxd -r -p | sha256sum
  From this post from 6 years ago: <a href="https://www.reddit.com/r/crypto/comments/guctw4/finding_sha256_partial_collisions_via_the_bitcoin/" rel="nofollow">https://www.reddit.com/r/crypto/comments/guctw4/finding_sha2...
  1. Retr0id · 1789906403 · focus · HN ↗
    True, I forgot about that! It's more fun when the inputs are printable ascii, though :P
    It should also be easy to beat with just a few GPU weeks.
    gpugreg · 1789913105 · focus · HN ↗
    I agree that ASCII is definitely cooler, for example when personalizing the hashed data as in your example.

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