The remote host is missing an update to xfs announced via advisory DSA 1342-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201342-1

It was discovered that a race condition in the init.d script of the X Font Server allows the modification of file permissions of arbitrary files if the local administrator can be tricked into restarting the X font server. For the oldstable distribution (sarge) xfs is present as part of the monolithic xfree86 package. A fix will be provided along with a future security update. For the stable distribution (etch) this problem has been fixed in version 1.0.1-6. For the unstable distribution (sid) this problem has been fixed in version 1.0.4-2. We recommend that you upgrade your xfs package.