The postfix mail transport agent in Debian 3.0 contains two
vulnerabilities:
CAN-2003-0468: Postfix would allow an attacker to bounce-scan private
networks or use the daemon as a DDoS tool by forcing the daemon to
connect to an arbitrary service at an arbitrary IP address and
either receiving a bounce message or observing queue operations to
infer the status of the delivery attempt.
CAN-2003-0540: a malformed envelope address can 1) cause the queue
manager to lock up until an entry is removed from the queue and 2)
lock up the smtp listener leading to a denial of service.
For the current stable distribution (woody) these problems have been
fixed in version 1.1.11-0.woody3.
For the unstable distribution (sid) these problems will be fixed soon.
We recommend that you update your postfix package.