The remote host is missing an update to zope announced via advisory DSA 490-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%20490-1

A vulnerability has been discovered in the index support of the ZCatalog plug-in in Zope, an open source web application server. A flaw in the security settings of ZCatalog allows anonymous users to call arbitrary methods of catalog indexes. The vulnerability also allows untrusted code to do the same. For the stable distribution (woody) this problem has been fixed in version 2.5.1-1woody1. For the unstable distribution (sid) this problem has been fixed in version 2.6.0-0.1 and higher. We recommend that you upgrade your zope package.