Gentoo Linux Security Advisory GLSA 200705-17 – Stefan Esser discovered that mod_security processes NULL characters as terminators in POST requests using the application/x-www-form-urlencoded encoding type, while other parsers used in web applications do not. Versions less than 2.1.1 are affected.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/56823/glsa-200705-17.txt
Source: https://packetstormsecurity.com/files/56823/Gentoo-Linux-Security-Advisory-200705-17.html