The remote host is missing an update to dbus announced via advisory DSA 1837-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201837-1

It was discovered that the dbus_signature_validate function in dbus, a simple interprocess messaging system, is prone to a denial of service attack. This issue was caused by an incorrect fix for DSA-1658-1. For the stable distribution (lenny), this problem has been fixed in version 1.2.1-5+lenny1. For the oldstable distribution (etch), this problem has been fixed in version 1.0.2-1+etch3. Packages for ia64 and s390 will be released once they are available. For the testing distribution (squeeze) and the unstable distribution (sid), this problem has been fixed in version 1.2.14-1. We recommend that you upgrade your dbus packages.