Writing your own graudit signatures is relatively easy. Mastering regular expressions can be helpful, but in their simplest form a list of words will do. I have tried to document some of the common pitfalls that might creep up on you in my Ruxmon presentation, but I know how "useful" a single slide can be. I am catching up on graudit documentation and signatures is just around the corner. Until then, I thought I would share with you some of the databases I use when looking for low hanging fruit and want to reduce the information overload (noise) that you normally get from the php ruleset. Signatures after the break to avoid spamming rss readers.
Benchmarking might not be the correct term as graudit does not have the capacity to determine if a signature match is in fact a vulnerability or not. It only highlights a potential problem area so you can pay closer attention to it. Like most signature based approaches it does stand a fairly good chance of catching low hanging fruit, but certain kind of vulnerabilities will remain impossible to detect. None-the-less I am aiming to improve the standard of the signature sets, so from now on graudit will be "benchmarked" on each release.
To avoid writing signatures for specific vulnerabilities I am using two vulnerable applications to benchmark graudit with;
* Multillidae
* Damn Vulnerable Web Application
My hope is to approximate 100% low and 75% medium detection rate by version 2.0. Now to find some non PHP equivalents for the other languages.