CVE-2011-3190 Apache Tomcat Authentication bypass and information disclosure Severity: Important Vendor: The Apache Software Foundation Versions Affected: - Tomcat 7.0.0 to 7.0.20 - Tomcat 6.0.0 to 6.0.33 - Tomcat 5.5.0 to 5.5.33 - Earlier, unsupported versions may also be affected Description: Apache Tomcat supports the AJP protocol which is used with reverse proxies to pass requests and associated data about the request from the reverse proxy to Tomcat. The AJP protocol is designed so that when a request includes a request body, an unsolicited AJP message is sent to Tomcat that includes the first part (or possibly all) of the request body. In certain circumstances, Tomcat did not process this message as a request body but as a new request. This permitted an attacker to have full control over the AJP message which allowed an attacker to (amongst other things): - insert the name of an authenticated user - insert any client IP address (potentially bypassing any client IP address filtering) - trigger the mixing of responses between users The following AJP connector implementations are not affected: org.apache.jk.server.JkCoyoteHandler (5.5.x - default, 6.0.x - default) The following AJP connector implementations are affected: org.apache.coyote.ajp.AjpProtocol (6.0.x, 7.0.x - default) org.apache.coyote.ajp.AjpNioProtocol (7.0.x) org.apache.coyote.ajp.AjpAprProtocol (5.5.x, 6.0.x, 7.0.x) Further, this issue only applies if all of the following are are true for at least one resource: - POST requests are accepted - The request body is not processed Example: See https://issues.apache.org/bugzilla/show_bug.cgi?id=51698 Mitigation: Users of affected versions should apply one of the following mitigations: - Upgrade to a version of Apache Tomcat that includes a fix for this issue when available - Apply the appropriate patch - 7.0.x http://svn.apache.org/viewvc?rev=1162958&view=rev - 6.0.x http://svn.apache.org/viewvc?rev=1162959&view=rev - 5.5.x http://svn.apache.org/viewvc?rev=1162960&view=rev - Configure the reverse proxy and Tomcat's AJP connector(s) to use the requiredSecret attribute - Use the org.apache.jk.server.JkCoyoteHandler AJP connector (not available for Tomcat 7.0.x) Credit: The issue was reported via Apache Tomcat's public issue tracker. The Apache Tomcat security team strongly discourages reporting of undisclosed vulnerabilities via public channels. All Apache Tomcat security vulnerabilities should be reported to the private security team mailing list: security (at) tomcat.apache (dot) org [email concealed] References: http://tomcat.apache.org/security.html http://tomcat.apache.org/security-7.html http://tomcat.apache.org/security-6.html http://tomcat.apache.org/security-5.html https://issues.apache.org/bugzilla/show_bug.cgi?id=51698