Re: md5 hashes used in security announcements

[Bas Steendijk <beware@bircd.org>]

Florian Weimer wrote:
> * Bas Steendijk:
>
> > i have sent an email a while ago about the security implications of
> > using MD5 hashes in the security announcements (DSA), but i didn't get
> > any reply at all from this. has it been overlooked?
>
> I don't know to which address you sent the address, so I don't know if
> it's been overlooked.
>
> My general take on this issue is that for this particular purpose, we
> will stop using MD5 when someone comes up with an actual collision for a
> hash published in a DSA.  It's not that these hashes are used for
> automated processing.  We can't do anything about the old DSAs
> containing MD5 hashes anyway.

2 files with a colliding hash can only be made by someone who can 
influence the creation of the file (thus, someone inside debian). he can 
make a "good" and a "bad" version of a package with the same MD5, and 
the same size. for someone to make a file with the same hash without 
influence in the creation of the original file would be a preimage attack.