The remote host is missing an update to avahi announced via advisory DSA 1690-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201690-1

Two denial of service conditions were discovered in avahi, a Multicast DNS implementation. Huge Dias discovered that the avahi daemon aborts with an assert error if it encounters a UDP packet with source port 0 (CVE-2008-5081). It was discovered that the avahi daemon aborts with an assert error if it receives an empty TXT record over D-Bus (CVE-2007-3372). For the stable distribution (etch), these problems have been fixed in version 0.6.16-3etch2. For the unstable distribution (sid), these problems have been fixed in version 0.6.23-3. We recommend that you upgrade your avahi packages.