Summary
The remote host is missing an update as announced
via advisory SSA:2009-120-01.
Solution
https://secure1.securityspace.com/smysecure/catid.html?in=SSA:2009-120-01
Insight
New ruby packages are available for Slackware 11.0, 12.0, 12.1, 12.2, and -current to fix a problem with REXML and other security issues.
For details about the REXML issue, see:
http://www.ruby-lang.org/en/news/2008/08/23/dos-vulnerability-in-rexml/
A full list may be found in the ChangeLog file included with the source code.