The remote host is missing an update to w3m, w3m-ssl announced via advisory DSA 251-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%20251-1

Hironori Sakamoto, one of the w3m developers, found two security vulnerabilities in w3m and associated programs. The w3m browser does not properly escape HTML tags in frame contents and img alt attributes. A malicious HTML frame or img alt attribute may deceive a user to send his local cookies which are used for configuration. The information is not leaked automatically, though. For the stable distribution (woody) these problems have been fixed in version 0.3-2.4. The old stable distribution (potato) is not affected by these problems. For the unstable distribution (sid) these problems have been fixed in version 0.3.2.2-1 and later. We recommend that you upgrade your w3m and w3m-ssl packages.