The remote host is missing an update to popfile announced via advisory DSA 1061-1. It has been discovered that popfile, a bayesian mail classifier, can be forced into a crash through malformed character sets within email messages, which allows denial of service. The old stable distribution (woody) does not contain popfile packages.
For the stable distribution (sarge) this problem has been fixed in version 0.22.2-2sarge1. For the unstable distribution (sid) this problem has been fixed in version 0.22.4-1. We recommend that you upgrade your popfile package. https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201061-1