The remote host is missing an update to moin announced via advisory DSA 2538-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%202538-1

It was discovered that Moin, a Python clone of WikiWiki, incorrectly evaluates ACLs when virtual groups are involved. This may allow certain users to have additional permissions (privilege escalation) or lack expected permissions. For the stable distribution (squeeze), this problem has been fixed in version 1.9.3-1+squeeze2. For the testing distribution (wheezy), this problem will be fixed soon. For the unstable distribution (sid), this problem has been fixed in version 1.9.4-8. We recommend that you upgrade your moin packages.