Debian Security Advisory 1852-1 – It was discovered that fetchmail, a full-featured remote mail retrieval and forwarding utility, is vulnerable to the “Null Prefix Attacks Against SSL/TLS Certificates” recently published at the Blackhat conference. This allows an attacker to perform undetected man-in-the-middle attacks via a crafted ITU-T X.509 certificate with an injected null byte in the subjectAltName or Common Name fields.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/80191/dsa-1852-1.txt
Source: https://packetstormsecurity.com/files/80191/Debian-Linux-Security-Advisory-1852-1.html