The remote host is missing an update to imp4 announced via advisory DSA 1770-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201770-1

Several vulnerabilities have been found in imp4, a webmail component for the horde framework. The Common Vulnerabilities and Exposures project identifies the following problems: CVE-2008-4182 It was discovered that imp4 suffers from a cross-site scripting (XSS) attack via the user field in an IMAP session, which allows attackers to inject arbitrary HTML code. CVE-2009-0930 It was discovered that imp4 is prone to several cross-site scripting (XSS) attacks via several vectors in the mail code allowing attackers to inject arbitrary HTML code. For the oldstable distribution (etch), these problems have been fixed in version 4.1.3-4etch1. For the stable distribution (lenny), these problems have been fixed in version 4.2-4, which was already included in the lenny release. For the testing distribution (squeeze) and the unstable distribution (sid), these problems have been fixed in version 4.2-4. We recommend that you upgrade your imp4 packages.