The remote host is missing an update to squid3 announced via advisory DSA 2304-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%202304-1

Ben Hawkes discovered that squid3, a full featured Web Proxy cache (HTTP proxy), is vulnerable to a buffer overflow when processing gopher server replies. An attacker can exploit this flaw by connecting to a gopher server that returns lines longer than 4096 bytes. This may result in denial of service conditions (daemon crash) or the possibly the execution of arbitrary code with rights of the squid daemon. For the oldstable distribution (lenny), this problem has been fixed in version 3.0.STABLE8-3+lenny5. For the stable distribution (squeeze), this problem has been fixed in version 3.1.6-1.2+squeeze1. For the testing distribution (wheezy), this problem has been fixed in version 3.1.15-1. For the unstable distribution (sid), this problem has been fixed in version 3.1.15-1. We recommend that you upgrade your squid3 packages.