Why would a sysadmin have set PERL_HASH_SEED=0?

Anyway, rather than brute-forcing, a real attack would use the known hash seed and the known hash algorithm, and with those known factors it's fairly trivial to offline generate a set of short strings which all map to the same hash bucket slot (but not necessarily to the same hash value, which has more bits than the number of buckets).

But no, I'm not going to explain how.

Dave.

In reply to Re: Hash Collisions with PERL_HASH_SEED=0 by dave_the_m
in thread Hash Collisions with PERL_HASH_SEED=0 by jimpudar

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