Debian Security Advisory DSA 849-1 – Supernaut noticed that shorewall, the Shoreline Firewall, could generate an iptables configuration which is significantly more permissive than the rule set given in the shorewall configuration, if MAC verification are used in a non-default manner.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/40521/dsa-849-1.txt
Source: https://packetstormsecurity.com/files/40521/Debian-Linux-Security-Advisory-849-1.html