On: Efficiently Generating Python Hash Collisions

[tromp]

Finding (cycles of) collisions in siphash is used as a memory-hard Proof-of-Work:

https://github.com/tromp/cuckoo

[rurban → tromp]

Only for hash tables which use all bits. (e.g. prime sized).

Almost nobody does. For normal power-of-2 hash tables finding collisions in the lowest bits leading to a successful amplification is trivial by brute-force. Since Siphash is so slow it can last up to 4 minutes, for smaller tables still < 5s.