On Mon, 6 Dec 2004, Dan Kaminsky wrote:

> I've been doing some analysis on MD5 collision announced by Wang et al.
> Short version: Yes, Virginia, there is no such thing as a safe hash
> collision -- at least in a function that's specified to be
> cryptographically secure. The full details may be acquired at the
> following link:

The short-term fix seems to be something I've been recommending for a
while:

Compute hashes with both SHA-1 and MD5.

The chance of one algorithm becoming compromised in the mid-term is
relatively high IMHO (I was responsible for a PKI system which had to keep
integrity for 20 year periods of time - not an easy task considering what
we don't know about the future). The chance of two becoming compromised
is relatively less. The chance of a problem with MD5 and SHA-1 allowing
two different files to have collisions in both algorithms in *BOTH* is
very very small.

--
Joel

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