Whatever happened to SHA-256 support in Git
> There is also the risk (which cannot really be made to go away) that the longer hashes used with SHA-256 may break tools developed outside of the Git projectEasy fix if that is really an issue, just truncate sha-256. The length of the hash is not the issue that needs fixing (even if its a nice side benefit).> that is only the first step in the development of a successful attack. Finding a collision of any type is hard; finding one that is still working code, that has the functionality the attacker is after, and that looks reasonable to both humans and compilers is quite a bit harder — if it is possible at all.I mean, if you have any sort of binary files in your repo, that's pretty doubtful.The way you mostly do this, is the colliding part is a short binary blob which is embedded, and then the file has code outside the colliding part that does different things depending on the value of the blob.Yeah, getting that past human review with a source code file  is going to be tricky. Otoh if you have any sort of binary assets in your git, (this might even include images depending on the attack goals, e.g. goatse attack) this seems a lot more plausibleP.s. to be clear, i agree that sha-1dc variant removes most of the urgency.