The remote host is missing an update to squid announced via advisory DSA 809-3.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%20809-3

Kosa Attila discovered that the security update DSA 809-2 contained a regression in the packages for the old stable distribution (woody). The orginal advisory text follows: Certain aborted requests that trigger an assertion in squid, the popular WWW proxy cache, may allow remote attackers to cause a denial of service. This update also fixes a regression caused by DSA 751. For the oldstable distribution (woody) this problem has been fixed in version 2.4.6-2woody11. We recommend that you upgrade your squid package.