squid3 - invalid memory deallocation

It was discovered that the IPv6 support code in Squid does not
properly handle certain DNS responses, resulting in deallocation of an
invalid pointer and a daemon crash.

The squid package and the version of Squid 3 shipped in lenny lack IPv6
support and are not affected by this issue.

For the stable distribution (squeeze), this problem has been fixed in
version 3.1.6-1.2+squeeze2.

For the testing distribution (wheezy) and the unstable distribution
(sid), this problem has been fixed in version 3.1.18-1.

We recommend that you upgrade your squid3 packages.