Hewlett-Packard Company Information for VU#434566

Apache mod_rewrite vulnerable to buffer overflow via crafted regular expression



Vendor Statement

Hash: SHA1

**REVISED 01**
Originally issued: 18 November 2003
Last revised: 19 November 2003
SSRT3663 Apache HTTP Server mod_cgid, mod_alias, mod_rewrite
NOTICE: There are no restrictions for distribution of this
       Bulletin provided that it remains complete and intact.

The information in the following Security Bulletin should be
acted upon as soon as possible.  Hewlett-Packard Company will
not be liable for any consequences to any customer resulting
from customer's failure to fully implement instructions in this
Security Bulletin as soon as possible.

PROBLEM: 1. mod_cgid mishandling of CGI redirect paths could
           result in CGI output going to the wrong client when a
           threaded MPM is used.

            More details are available at:

         2. A buffer overflow could occur in mod_alias and
           mod_rewrite when a regular expression with more than
           9 captures is configured.

            More details are available at:

IMPACT: Potential Denial of Service or execute arbitrary code.

PLATFORM: HP9000 Servers running HP-UX release B.11.00, B.11.11,
         B.11.20, B.11.22, and B.11.23 with versions of the
         following products are affected, and represented as:
              product-name, version (product-tag/bundle-tag)

          product-name, version (product-tag/bundle-tag)

          - hp apache-based web server,
           or earlier (HPApache/B9416AA)
           This product includes Apache 2.0.43.

          - hp-ux apache-based web server, v.
           or earlier (hpuxwsAPACHE/hpuxwsApache)
           This product includes Apache 2.0.47.

          - hp apache-based web server (with IPv6 support),
  or earlier (HPApache/B9416BA)
           This product includes Apache 2.0.43.

          - hp-ux apache-based web server(with IPv6 support),
           v. or earlier (hpuxwsAPACHE/hpuxwsApache)
           This product includes Apache 2.0.47.

SOLUTION: For HP-UX releases B.11.00, B.11.11, B.11.20, B.11.22
         and B.11.23 download new HP Apache product from

          For HPApache/B9416AA, HPApache/B9416BA and
             hpuxwsAPACHE/hpuxwsApache download the following:

          - hp-ux apache-based web server (with IPv4)
           v. or later (hpuxwsAPACHE/hpuxwsApache)
           This product includes Apache 2.0.48.

          - hp-ux apache-based web server(with IPv6 support),
           v. or later (hpuxwsAPACHE/hpuxwsApache)
           This product includes Apache 2.0.48.

MANUAL ACTIONS: Yes - Non-Update
               Install the product containing the fix.
               For customers with HPApache/B9416AA
               HPApache/B9416BA installed, the fix requires
               migration to hpuxwsAPACHE/hpuxwsApache and
               removing the affected products from the system.

AVAILABILITY: Complete product bundles are available now on

CHANGE SUMMARY:  Rev. 01 Corrected typo in version number
**REVISED  01**
A. Background
  The Common Vulnerabilities and Exposures project
  <http://cve.mitre.org/> has identified potential
  vulnerabilities in the Apache HTTP Server (CAN-2003-0789, and
  CAN-2003-0542).  It affects the following HP product
  numbers/versions on HP-UX releases B.11.00, B.11.11, B.11.20,
  B.11.22, and B.11.23:

   - hp apache-based web server, or earlier

   - hp-ux apache-based web server, v. or earlier

   - hp apache-based web server, (with IPv6 support)
    or earlier (HPApache/B9416BA)

   - hp-ux apache-based web server (with IPv6 support),
    v. or earlier (hpuxwsAPACHE/hpuxwsApache)


   The following is a list of affected filesets or patches
  and fix information. To determine if a system has an
  affected version, search the output of
  "swlist -a revision -l fileset" for an affected fileset
  or patch, then determine if a fixed revision or applicable
  patch is installed.

         HP-UX B.11.00
        HP-UX B.11.11
        HP-UX B.11.20
        HP-UX B.11.22
        HP-UX B.11.23
--->>   fix: install hp-ux apache-based web server, v.
             or later.


B. Recommended solution
  The Apache Software Foundation has released Apache 2.0.48 as
  the best known version that fixes the problems identified in
  the above mentioned issues.

   For customers using HPApache/B9416AA HPApache/B9416BA and
  hpuxwsAPACHE/hpuxwsApache, HP has incorporated Apache 2.0.48
  in the following product:
  - hp-ux apache-based web server v. or later

   Check for Apache Installation
  To determine if the Apache web server from HP is installed on
  your system, use Software Distributor's swlist command.  All
  three versions products may co-exist on a single system.

   For example, the results of the command
    swlist -l product | grep -i apache

     HPApache  HP Apache-based Web Server
    hpuxwsAPACHE  A.   HP-UX Apache-based Web Server

   Stop Apache
  Before updating, make sure to stop any previous Apache binary.
  Otherwise, the previous binary will continue running,
  preventing the new one from starting, although the installation
  would be successful.

   After determining which Apache is installed, stop Apache with
  the following commands:

     for HPApache:        /opt/hpapache2/bin/apachectl stop
    for hpuxwsAPACHE:    /opt/hpws/apache/bin/apachectl stop

   Download and Install Apache
  - Download Apache from Software Depot using the previously
    mentioned links.
  - Verify successful download by comparing the cksum with the
    value specified on the installation web page.
  - Use SD to swinstall the depot.
  - For customers with HPApache/B9416BA installed, migrate to
    hpuxwsAPACHE/hpuxwsApache and remove the affected products
    from the system.

   Installation of this new version of HP Apache over an existing
  HP Apache installation is supported, while installation over a
  non-HP Apache is NOT supported.

   Removing Apache Installation
  If you rather remove Apache from your system than install a
  newer version to resolve the security problem, use both
  Software Distributor's "swremove" command and also "rm -rf" the
  home location as specified in the rc.config.d file "HOME"

   To find the files containing HOME variables in the
  /etc/rc.config.d directory:

     %ls /etc/rc.config.d | grep apache

C. To subscribe to automatically receive future NEW HP Security
  Bulletins from the HP IT Resource Center via electronic
  mail, do the following:

   Use your browser to get to the HP IT Resource Center page


   Use the 'Login' tab at the left side of the screen to login
  using your ID and password.  Use your existing login or the
  "Register" button at the left to create a login, in order to
  gain access to many areas of the ITRC.  Remember to save the
  User ID assigned to you, and your password.

   In the left most frame select "Maintenance and Support".

   Under the "Notifications" section (near the bottom of
  the page), select "Support Information Digests".

   To -subscribe- to future HP Security Bulletins or other
  Technical Digests, click the check box (in the left column)
  for the appropriate digest and then click the "Update
  Subscriptions" button at the bottom of the page.


   To -review- bulletins already released, select the link
  (in the middle column) for the appropriate digest.

   NOTE: Using your itrc account security bulletins can be
        found here:

   To -gain access- to the Security Patch Matrix, select
  the link for "The Security Bulletins Archive".  (near the
  bottom of the page)  Once in the archive the third link is
  to the current Security Patch Matrix. Updated daily, this
  matrix categorizes security patches by platform/OS release,
  and by bulletin topic.  Security Patch Check completely
  automates the process of reviewing the patch matrix for
  11.XX systems.  Please note that installing the patches
  listed in the Security Patch Matrix will completely
  implement a security bulletin _only_ if the MANUAL ACTIONS
  field specifies "No."

   The Security Patch Check tool can verify that a security
  bulletin has been implemented on HP-UX 11.XX systems providing
  that the fix is completely implemented in a patch with no
  manual actions required.  The Security Patch Check tool cannot
  verify fixes implemented via a product upgrade.

   For information on the Security Patch Check tool, see:

   The security patch matrix is also available via anonymous


   On the "Support Information Digest Main" page:
  click on the "HP Security Bulletin Archive".

   The PGP key used to sign this bulletin is available from
  several PGP Public Key servers.  The key identification
  information is:

     HP Security Response Team (Security Bulletin signing only)
     Fingerprint =
       6002 6019 BFC1 BC62 F079 862E E01F 3AFC 2D2A 7D59

   If you have problems locating the key please write to
  security-alert@hp.com.  Please note that this key is
  for signing bulletins only and is not the key returned
  by sending 'get key' to security-alert@hp.com.

D. To report new security vulnerabilities, send email to


   Please encrypt any exploit information using the
  security-alert PGP key, available from your local key
  server, or by sending a message with a -subject- (not body)
  of 'get key' (no quotes) to security-alert@hp.com.


(c)Copyright 2003 Hewlett-Packard Company
Hewlett-Packard Company shall not be liable for technical or
editorial errors or omissions contained herein. The information
in this document is subject to change without notice.
Hewlett-Packard Company and the names of HP products referenced
herein are trademarks and/or service marks of Hewlett-Packard
Company.  Other product and company names mentioned herein may be
trademarks and/or service marks of their respective owners.

- --

Version: PGP 8.0


Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.

Vendor References



The CERT/CC has no additional comments at this time.

If you have feedback, comments, or additional information about this vulnerability, please send us email.