The remote host is missing an update to pidgin announced via advisory DSA 1805-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201805-1

Several vulnerabilities have been discovered in Pidgin, a graphical multi-protocol instant messaging client. The Common Vulnerabilities and Exposures project identifies the following problems: CVE-2009-1373 A buffer overflow in the Jabber file transfer code may lead to denial of service or the execution of arbitrary code. CVE-2009-1375 Memory corruption in an internal library may lead to denial of service. CVE-2009-1376 The patch provided for the security issue tracked as CVE-2008-2927 - integer overflows in the MSN protocol handler - was found to be incomplete. The old stable distribution (etch) is affected under the source package name gaim. However, due to build problems the updated packages couldn't be released along with the stable version. It will be released once the build problem is resolved. For the stable distribution (lenny), these problems have been fixed in version 2.4.3-4lenny2. For the unstable distribution (sid), these problems have been fixed in version 2.5.6-1. We recommend that you upgrade your pidgin packages.