A worm is making the round infecting JBoss application servers. JBoss is an open source Java based application server and it is currently maintained by RedHat.

The worm exploits and older configuration problem in JBoss, which only authenticated GET and POST requests. It was possible to use other methods to execute arbitrary code without authentication. The problem has been fixed last year, but there are apparently still a number of vulnerable installs out there.

If you do run JBoss, please make sure to read the instructions posted by RedHat here:

http://community.jboss.org/blogs/mjc/2011/10/20/statement-regarding-security-threat-to-jboss-application-server

Analysis of the worm:

http://pastebin.com/U7fPMxet

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Johannes B. Ullrich, Ph.D.

SANS Technology Institute

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