(RHSA-2016:0062) Moderate: Red Hat JBoss Web Server 2.1.0 security update

Red Hat JBoss Web Server is a fully integrated and certified set of
components for hosting Java web applications. It is comprised of the Apache
HTTP Server, the Apache Tomcat Servlet container, Apache Tomcat Connector
(mod_jk), JBoss HTTP Connector (mod_cluster), Hibernate, and the Tomcat
Native library.

Multiple flaws were found in the way httpd parsed HTTP requests and
responses using chunked transfer encoding. A remote attacker could use
these flaws to create a specially crafted request, which httpd would decode
differently from an HTTP proxy software in front of it, possibly leading to
HTTP request smuggling attacks. (CVE-2015-3183)

A denial of service flaw was found in the implementation of hash arrays in
Expat. An attacker could use this flaw to make an application using Expat
consume an excessive amount of CPU time by providing a specially-crafted
XML file that triggers multiple hash function collisions. To mitigate this
issue, randomization has been added to the hash function to reduce the
chance of an attacker successfully causing intentional collisions.
(CVE-2012-0876)

A flaw was found in the way httpd handled HTTP Trailer headers when
processing requests using chunked encoding. A malicious client could use
Trailer headers to set additional HTTP headers after header processing was
performed by other modules. This could, for example, lead to a bypass of
header restrictions defined with mod_headers. (CVE-2013-5704)

All users of Red Hat JBoss Web Server 2.1.0 as provided from the Red Hat
Customer Portal are advised to apply this update. The Red Hat JBoss Web
Server process must be restarted for the update to take effect.