rapid7/metasploit-framework — pull request #382 by FireFart (2012-05-13 19:06:49+00:00)
Title: Hashcollision DOS

Ported my Hashcollisionscript to metasploit.

A variety of programming languages suffer from a denial-of-service (DoS) condition against storage functions of key/value pairs in hash data structures, the condition can be leveraged by exploiting predictable collisions in the underlying hashing algorithms.
The issue finds particular exposure in web server applications and/or frameworks. In particular, the lack of sufficient limits for the number of parameters in POST requests in conjunction with the predictable collision properties in the hashing functions of the underlying languages can render web applications vulnerable to the DoS condition. The attacker, using specially crafted HTTP requests, can lead to a 100% of CPU usage which can last up to several hours depending on the targeted application and server performance, the amplification effect is considerable and requires little bandwidth and time on the attacker side.

Tested with PHP + httpd, Tomcat, Glassfish, Geronimo. Generates a random Payload to bypass IDS.