I just finished reading the presenation slides from DEFCON and
fortunately it doesn't to be anything earth-shattering, two exploits
are described:

1. A format string vulnerability in the FINGER client (VAX only). The
example shellcode is stored on a remote system's .plan file and forces
the victim FINGER client to modify SYSUAF.

2. A CLI buffer overflow on Alphas. Basically any input over 511
characters causes an overflow, it seems to be possible to have a
privileged process execute arbitrary code.

Anyway, this is from a 10 minute reading of the slides, I might have
missed something, but the important thing (IMHO) is that neither of
these exploits are possible from remote but require a malicious user
to already have an account on the targeted system.

Sampsa