A GUID is not a cryptographic hash function. In any case, in 2023 I back-of-the-... | Hacker News

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		Retr0id 6 months ago \| parent \| context \| favorite \| on: Guid Smash A GUID is not a cryptographic hash function. In any case, in 2023 I back-of-the-envelope estimated that you could compute 2^64 SHA256 for ~$100K, using rented GPU capacity https://www.da.vidbuchanan.co.uk/blog/colliding-secure-hashe...

8organicbits 6 months ago [–]

That's great analysis. As you call out in the post, the 2^64 value is used to attack SHA256-128 (SHA256 truncated to 128 bits). NIST recommends at least SHA-224, which makes sense given your conclusions.

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