WAF Virtual Patching Challenge: Securing WebGoat with ModSecurity Ryan Barnett Breach Security (www.breach.com) rbarnett@breach.com Revision 1 (January 20, 2009) Abstract In this paper, we present the technical details behind a virtual patch, which is a critical protection function provided by web application firewalls (WAFs). A virtual patch is a powerful, agile mitigation strategy to quickly hel