The remote host is missing an update to xmlsec1 announced via advisory DSA 2219-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%202219-1

Nicolas Gregoire discovered that the XML Security Library xmlsec allowed remote attackers to create or overwrite arbitrary files through specially crafted XML files using the libxslt output extension and a ds:Transform element during signature verification. For the oldstable distribution (lenny), this problem has been fixed in version 1.2.9-5+lenny1. For the stable distribution (squeeze), this problem has been fixed in version 1.2.14-1+squeeze1. For the testing distribution (wheezy) and unstable distribution (sid), this problem has been fixed in version 1.2.14-1.1. We recommend that you upgrade your xmlsec1 packages.