The remote host is missing an update to glib2.0 announced via advisory DSA 1747-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201747-1

Diego Petten discovered that glib2.0, the GLib library of C routines, handles large strings insecurely via its Base64 encoding functions. This could possible lead to the execution of arbitrary code. For the stable distribution (lenny), this problem has been fixed in version 2.16.6-1+lenny1. For the oldstable distribution (etch), this problem has been fixed in version 2.12.4-2+etch1. For the testing distribution (squeeze), this problem will be fixed soon. For the unstable distribution (sid), this problem has been fixed in version 2.20.0-1. We recommend that you upgrade your glib2.0 packages.