rssh 2.3.3 and earlier allows local users to bypass intended restricted shell access via crafted environment variables in the command line.
http://www.securityfocus.com/bid/53430
http://www.openwall.com/lists/oss-security/2012/11/28/3
http://www.openwall.com/lists/oss-security/2012/08/11/3
http://www.openwall.com/lists/oss-security/2012/08/10/7
http://www.debian.org/security/2012/dsa-2530
http://sourceforge.net/mailarchive/message.php?msg_id=29235647
http://secunia.com/advisories/50272
http://archives.neohapsis.com/archives/bugtraq/2012-11/0101.html
http://archives.neohapsis.com/archives/bugtraq/2012-05/0036.html