RHSA-2013:0265 - Security Advisory

Topic

An update for the Apache Tomcat 6 component for JBoss Enterprise Web Server
2.0.0 that fixes multiple security issues is now available from the Red Hat
Customer Portal.

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.

Description

Apache Tomcat is a servlet container.

It was found that sending a request without a session identifier to a
protected resource could bypass the Cross-Site Request Forgery (CSRF)
prevention filter. A remote attacker could use this flaw to perform
CSRF attacks against applications that rely on the CSRF prevention filter
and do not contain internal mitigation for CSRF. (CVE-2012-4431)

A flaw was found in the way Tomcat handled sendfile operations when using
the HTTP NIO (Non-Blocking I/O) connector and HTTPS. A remote attacker
could use this flaw to cause a denial of service (infinite loop). The HTTP
NIO connector is used by default in JBoss Enterprise Web Server. The Apache
Portable Runtime (APR) connector from the Tomcat Native library was not
affected by this flaw. (CVE-2012-4534)

Multiple weaknesses were found in the Tomcat DIGEST authentication
implementation, effectively reducing the security normally provided by
DIGEST authentication. A remote attacker could use these flaws to perform
replay attacks in some circumstances. (CVE-2012-5885, CVE-2012-5886,
CVE-2012-5887)

A denial of service flaw was found in the way the Tomcat HTTP NIO connector
enforced limits on the permitted size of request headers. A remote attacker
could use this flaw to trigger an OutOfMemoryError by sending a
specially-crafted request with very large headers. The HTTP NIO connector
is used by default in JBoss Enterprise Web Server. The APR connector from
the Tomcat Native library was not affected by this flaw. (CVE-2012-2733)

Warning: Before applying the update, back up your existing JBoss Enterprise
Web Server installation (including all applications and configuration
files).

All users of JBoss Enterprise Web Server 2.0.0 as provided from the Red Hat
Customer Portal are advised to apply this update.

Solution

The References section of this erratum contains a download link (you must
log in to download the update). Before applying the update, back up your
existing JBoss Enterprise Web Server installation (including all
applications and configuration files).

Tomcat must be restarted for this update to take effect.

Affected Products

• JBoss Enterprise Web Server 2 for RHEL 6 x86_64
• JBoss Enterprise Web Server Text-Only Advisories x86_64

Fixes

• BZ - 873664 - CVE-2012-5885 CVE-2012-5886 CVE-2012-5887 tomcat: three DIGEST authentication implementation issues
• BZ - 873695 - CVE-2012-2733 tomcat: HTTP NIO connector OOM DoS via a request with large headers
• BZ - 883636 - CVE-2012-4431 Tomcat/JBoss Web - Bypass of CSRF prevention filter
• BZ - 883637 - CVE-2012-4534 Tomcat - Denial Of Service when using NIO+SSL+sendfile

CVEs

• CVE-2012-2733
• CVE-2012-4431
• CVE-2012-4534
• CVE-2012-5885
• CVE-2012-5886
• CVE-2012-5887

References

• https://access.redhat.com/security/updates/classification/#moderate
• https://access.redhat.com/jbossnetwork/restricted/listSoftware.html?downloadType=securityPatches&product=webserver&version=2.0.0
• http://tomcat.apache.org/security-6.html