Moderate: tomcat6 security and bug fix update
Security Advisory: Moderate
Updated tomcat6 packages that fix several security issues and one bug are
now available for Red Hat Enterprise Linux 6.
The Red Hat Security Response Team has rated this update as having moderate
security impact. Common Vulnerability Scoring System (CVSS) base scores,
which give detailed severity ratings, are available for each vulnerability
from the CVE links in the References section.
Apache Tomcat is a servlet container for the Java Servlet and JavaServer
Pages (JSP) technologies.
APR (Apache Portable Runtime) as mentioned in the CVE-2011-3190 and
CVE-2011-2526 descriptions does not refer to APR provided by the apr
packages. It refers to the implementation of APR provided by the Tomcat
Native library, which provides support for using APR with Tomcat. This
library is not shipped with Red Hat Enterprise Linux 6. This update
includes fixes for users who have elected to use APR with Tomcat by taking
the Tomcat Native library from a different product. Such a configuration is
not supported by Red Hat, however.
Multiple flaws were found in the way Tomcat handled HTTP DIGEST
authentication. These flaws weakened the Tomcat HTTP DIGEST authentication
implementation, subjecting it to some of the weaknesses of HTTP BASIC
authentication, for example, allowing remote attackers to perform session
replay attacks. (CVE-2011-1184)
A flaw was found in the way the Coyote (org.apache.coyote.ajp.AjpProcessor)
and APR (org.apache.coyote.ajp.AjpAprProcessor) Tomcat AJP (Apache JServ
Protocol) connectors processed certain POST requests. An attacker could
send a specially-crafted request that would cause the connector to treat
the message body as a new request. This allows arbitrary AJP messages to be
injected, possibly allowing an attacker to bypass a web application's
authentication checks and gain access to information they would otherwise
be unable to access. The JK (org.apache.jk.server.JkCoyoteHandler)
connector is used by default when the APR libraries are not present. The JK
connector is not affected by this flaw. (CVE-2011-3190)
A flaw was found in the Tomcat MemoryUserDatabase. If a runtime exception
occurred when creating a new user with a JMX client, that user's password
was logged to Tomcat log files. Note: By default, only administrators have
access to such log files. (CVE-2011-2204)
A flaw was found in the way Tomcat handled sendfile request attributes when
using the HTTP APR or NIO (Non-Blocking I/O) connector. A malicious web
application running on a Tomcat instance could use this flaw to bypass
security manager restrictions and gain access to files it would otherwise
be unable to access, or possibly terminate the Java Virtual Machine (JVM).
The HTTP blocking IO (BIO) connector, which is not vulnerable to this
issue, is used by default in Red Hat Enterprise Linux 6. (CVE-2011-2526)
Red Hat would like to thank the Apache Tomcat project for reporting the
This update also fixes the following bug:
Users of Tomcat should upgrade to these updated packages, which contain
backported patches to correct these issues. Tomcat must be restarted for
this update to take effect.
Before applying this update, make sure all previously-released errata
relevant to your system have been applied.
This update is available via the Red Hat Network. Details on how to
use the Red Hat Network to apply this update are available at