Re: [saag] Revision of "Attacks on Cryptographic Hashes in Internet Protocols"

Mouse <mouse@Rodents-Montreal.ORG> Thu, 29 November 2012 06:20 UTC

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From: Mouse <mouse@Rodents-Montreal.ORG>
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Subject: Re: [saag] Revision of "Attacks on Cryptographic Hashes in Internet Protocols"
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> The point that I wanted to make is: if the actual ISO image creator
> is untrustworthy and the hash function is not collision resistant,
> then it is possible for that person to make two images, one good and
> one bad.   This enables attacks on the system that are not otherwise
> possible, [...]

Ah!  I misunderstood.

Yes.  (I could quibble about how the colliding data blobs have to be
valid ISO images, but I suspect that part would border on trivial in
any realistic collision-resistance break, just as the MD5 collision
example I have managed to make both blobs valid PostScript programs.)

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