RHSA-2007:0360 - Security Advisory

Topic

Updated jbossas packages that fix multiple security issues in tomcat are
now available for Red Hat Application Stack.

This update has been rated as having Important security impact by the Red
Hat Security Response Team.

Description

Tomcat is a servlet container for Java Servlet and JavaServer Pages
technologies.

This update addresses the following issues:

Tomcat was found to accept multiple content-length headers in a
request. This could allow attackers to poison a web-cache, bypass web
application firewall protection, or conduct cross-site scripting attacks.
(CVE-2005-2090)

Tomcat permitted various characters as path delimiters. If Tomcat was used
behind certain proxies and configured to only proxy some contexts, an
attacker could construct an HTTP request to work around the context
restriction and potentially access non-proxied content. (CVE-2007-0450)

Users should upgrade to these erratum packages, which contain an update to
jbossas to include a version of Tomcat that resolves these issues. Updated
jakarta-commons-modeler packages are also included which correct a bug when
used with Tomcat 5.5.23.

Solution

Note: /etc/tomcat5/web.xml has been updated to disable directory listing by
default. If you have previously modified /etc/tomcat5/web.xml, this change
will not be made automatically and you should manually update the value for
the "listings" parameter to "false".

Note: In response to CVE-2007-0450, JBoss AS considers encoded slashes and
backslashes in URLs invalid and its usage will result in HTTP 400 error. It
is possible to allow encoded slashes and backslashes by following the steps
outlined below, however doing so will expose you to CVE-2007-0450 related
attacks:

a) If you use the /var/lib/jbossas/bin/run.sh setup, please edit
/etc/jbossas/run.conf and append

• Dorg.apache.tomcat.util.buf.UDecoder.ALLOW_ENCODED_SLASH=true
• Dorg.apache.catalina.connector.CoyoteAdapter.ALLOW_BACKSLASH=true to the

string assigned to JAVA_OPTS

b) If you use the init script setup to run multiple JBoss AS services and
you wish to allow encoding by default on all services, please edit
/etc/jbossas/jbossas.conf and add the line JAVA_OPTS="${JAVA_OPTS}

• Dorg.apache.tomcat.util.buf.UDecoder.ALLOW_ENCODED_SLASH=true
• Dorg.apache.catalina.connector.CoyoteAdapter.ALLOW_BACKSLASH=true"

c) If you use the init script setup to run multiple JBoss AS services and
want to allow encoding of slashes and backslashes for a particular service,
please edit /etc/sysconfig/${NAME} (where NAME is the name of your service)
and add the line JAVA_OPTS="${JAVA_OPTS}

• Dorg.apache.tomcat.util.buf.UDecoder.ALLOW_ENCODED_SLASH=true
• Dorg.apache.catalina.connector.CoyoteAdapter.ALLOW_BACKSLASH=true"

Before applying this update, make sure that all previously-released
errata relevant to your system have been applied.

This update is available via Red Hat Network. Details on how to use
the Red Hat Network to apply this update are available at
http://kbase.redhat.com/faq/FAQ_58_10188

Affected Products

• Red Hat Application Stack 1 1 x86_64
• Red Hat Application Stack 1 1 i386

Fixes

• BZ - 238574 - CVE-2005-2090 multiple tomcat issues (CVE-2007-0450)

CVEs

• CVE-2007-1358
• CVE-2007-0450
• CVE-2005-2090

References

• http://tomcat.apache.org/security-5.html
• http://www.redhat.com/security/updates/classification/#important