The remote host is missing an update to nagios2 announced via advisory DSA 1883-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201883-1

Several vulnerabilities have been found in nagios2, ahost/service/network monitoring and management system. The Common Vulnerabilities and Exposures project identifies the following problems: Several cross-site scripting issues via several parameters were discovered in the CGI scripts, allowing attackers to inject arbitrary HTML code. In order to cover the different attack vectors, these issues have been assigned CVE-2007-5624, CVE-2007-5803 and CVE-2008-1360. For the oldstable distribution (etch), these problems have been fixed in version 2.6-2+etch4. The stable distribution (lenny) does not include nagios2 and nagios3 is not affected by these problems. The testing distribution (squeeze) and the unstable distribution (sid) do not contain nagios2 and nagios3 is not affected by these problems. We recommend that you upgrade your nagios2 packages.