CVE-2013-4286

The Tomcat fix for CVE-2005-2090 was not complete. It did not cover the following cases:

- content-length header with chunked encoding over any HTTP connector
- multiple content-length headers over any AJP connector

Requests with multiple content-length headers or with a content-length header when chunked encoding is being used should be rejected as invalid. When multiple components (firewalls, caches, proxies and Tomcat) process a sequence of requests where one or more requests contain either multiple content-length headers or a content-length header when chunked encoding is being used and several components do not reject the request and make different decisions as to which content-length header to use an attacker can poison a web-cache, perform an XSS attack and obtain sensitive information from requests other then their own. Tomcat now rejects requests with multiple content-length headers or with a content-length header when chunked encoding is being used.

This has been corrected in upstream versions 8.0.0-rc3 [1], 7.0.47 [2], and 6.0.39 [3].

References:

[1] http://svn.apache.org/viewvc?view=revision&revision=1521829
[2] http://svn.apache.org/viewvc?view=revision&revision=1521854
[3] http://svn.apache.org/viewvc?view=revision&revision=1552565
[4] https://bugzilla.redhat.com/show_bug.cgi?id=1069921