Debian Security Advisory 1659-1 – Dan Kaminsky discovered that libspf2, an implementation of the Sender Policy Framework (SPF) used by mail servers for mail filtering, handles malformed TXT records incorrectly, leading to a buffer overflow condition.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/71182/dsa-1659-1.txt
Source: https://packetstormsecurity.com/files/71182/Debian-Linux-Security-Advisory-1659-1.html