Debian Security Advisory 1544-1 – Amit Klein discovered that pdns-recursor, a caching DNS resolver, uses a weak random number generator to create DNS transaction IDs and UDP source port numbers. As a result, cache poisoning attacks were simplified.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/65399/dsa-1544-1.txt
Source: https://packetstormsecurity.com/files/65399/Debian-Linux-Security-Advisory-1544-1.html