Where I can find ModSecurity Rules for Specific Applications specially joomla, wordpress, mambo ?
There are separate files for PHPBB, Joomla and Wordpress as well as files covering XSS, RFI, LFI and SQL attacks in these and many other popular web applications. Mambo is included in this list.
Many of the rules have an identifier included that can tell you where the vulnerability was announced and/or documented. The tags appear like this:
Trustwave also publish lots of interesting research on the SpiderLabs blog and this often includes
You might also have some luck looking in the forums and bug tracking databases of the web applications in question. They are the people with the best incentive to create