SSRT4717 rev.0 Remote denial of service in Apache HTTP Server

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SSRT4717 rev.0 Remote denial of service in Apache HTTP Server

 There are no restrictions for distribution of this Bulletin
 provided that it remains complete and intact.

 The information in this Security bulletin should be acted upon
 as soon as possible.

INITIAL RELEASE:    25 April 2004

POTENTIAL SECURITY IMPACT:    Remote denial of service

HP Software Security Response Team

REFERENCES:    CAN-2003-0020, CAN-2004-0113,CAN-2004-0174


1. Apache does not filter terminal escape sequences from error
   logs, which could make it easier for attackers to insert those
   sequences into terminal emulators. More details are available

2. Starvation issue on listening sockets occurs when a short-lived
   connection on a rarely-accessed listening socket will cause a
   child to hold the accept mutex and block out new connections.
   More details are available at

3. Memory leak in mod_ssl allows a remote denial of service attack
   against a SSL-enabled server by sending plain HTTP requests to
   the SSL port. More details are available at

SUPPORTED SOFTWARE VERSIONS*:  ONLY impacted versions are listed.

HP9000 Servers running HP-UX release B.11.00, B.11.11, 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)

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

- - hp-ux apache-based web server, v.2.01 or earlier
 (hpuxwsAPACHE/hpuxwsApache) This product includes Apache 2.0.48.

- - 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.2.01 or
  earlier (hpuxwsAPACHE/hpuxwsApache)  This product includes
  Apache 2.0.48.


The Common Vulnerabilities and Exposures project has identified
potential vulnerabilities in the Apache HTTP Server
(CAN-2003-0020, CAN-2004-0174, and CAN-2004-0113).  It affects the
following HP product numbers/versions:

- - hp apache-based web server, or earlier

- - hp-ux apache-based web server, v.2.01 or earlier

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

- - hp-ux apache-based web server (with IPv6 support), v.2.01 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.11.22

HP-UX B.11.23




action: install hp-ux apache-based web server, v.2.03 or later


The Apache Software Foundation has released Apache 2.0.49 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 2.0.49 in the following product:

- - hp-ux apache-based web server v.2.03 or later /

Support ended for HP-UX Web Server Suite for HP-UX 11i v1.6
(11.22) after March 31, 2004. Starting from this release HP-UX Web
Server Suite for HP-UX 11i v1.6 (11.22) is no longer available or
supported.  Users of HP-UX Web Server Suite on HP-UX 11i v1.6 are
encouraged to update to HP-UX 11i v2 (11.23) and install the
latest HP-UX Web Server Suite for HP-UX 11i v2.

For HP-UX releases B.11.00, B.11.11, 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 IPv6 support), v.2.03 or
  later (hpuxwsAPACHE/hpuxwsApache). This product includes
  Apache 2.0.49. /

- - hp-ux apache-based web server (with IPv4) v.2.03 or later
  (hpuxwsAPACHE/hpuxwsApache).  This product includes
  Apache 2.0.49. /

- - hp-ux apache-based web server(with IPv6 support), v.2.03 or
  later (hpuxwsAPACHE/hpuxwsApache). This product includes
  Apache 2.0.49. /

For HP-UX release B.11.22

- - Starting from this release HP-UX Web Server Suite for HP-UX 11i
  v1.6 (11.22) is no longer available or supported.

Users of HP-UX Web Server Suite on HP-UX 11i v1.6 are encouraged
to update to HP-UX 11i v2 (11.23) and install the latest HP-UX Web
Server Suite for HP-UX 11i v2.

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.2.01 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[32]/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" variables.
To find the files containing HOME variables in the
/etc/rc.config.d directory:

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




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.

* The software product category that this Security Bulletin
 relates to is represented by the 5th and 6th characters of the
 Bulletin number: GN=General, MA=Management Agents, MI=Misc.
 3rd party, MP=HP-MPE/iX, NS=HP NonStop Servers, OV=HP OpenVMS,
 PI=HP Printing & Imaging, ST=HP Storage, TU=HP Tru64 UNIX,
 TL=Trusted Linux, UX=HP-UX, VV=Virtual Vault

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To review previously published Security Bulletins for HP-UX:

The HP-UX Security Patch Matrix is available here: =
Or via anonymous ftp: /

The HP-UX Security Patch Matrix, updated daily, categorizes
security patches by platform/OS release, and by Bulletin topic.
The Security Patch Check tool completely automates the process of
reviewing the Security Patch Matrix for HP-UX 11.XX Versions.
NOTE: Installing patches listed in the Security Patch Matrix will
completely implement the RESOLUTION in the Security Bulletin
_only_ if there are no MANUAL ACTIONS included.

The Security Patch Check tool can also verify that a Security
Bulletin RESOLUTION has been implemented on HP-UX 11.XX Versions
provided that no MANUAL ACTIONS were included. The Security Patch
Check tool cannot verify patches implemented via product upgrade.

For information on the Security Patch Check tool, see: /

REPORT: To report a potential security vulnerability with any HP
supported product, send Email to: It is
strongly recommended that security related information being
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information. To obtain the security-alert PGP key please send an
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System management and security procedures must be reviewed
frequently to maintain system integrity. HP is continually
reviewing and enhancing the security features of software products
to provide customers with current secure solutions.

"HP is broadly distributing this Security Bulletin in order to
bring to the attention of users of the affected HP products the
important security information contained in this Bulletin. HP
recommends that all users determine the applicability of this
information to their individual situations and take appropriate
action. HP does not warrant that this information is necessarily
accurate or complete for all user situations and, consequently,
HP will not be responsible for any damages resulting from user's
use or disregard of the information provided in this Bulletin.
To the extent permitted by law, HP disclaims all warranties,
either express or implied, including the warranties of
merchantability and fitness for a particular purpose, title
and non-infringement."

(c)Copyright 2004 Hewlett-Packard Development Company, L.P.
Hewlett-Packard Company shall not be liable for technical or
editorial errors or omissions contained herein. The information
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extent permitted by law, neither HP or its affiliates,
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or consequential damages including downtime cost; lost profits;
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The information in this document is subject to change without
notice. Hewlett-Packard Company and the names of Hewlett-Packard
products referenced herein are trademarks of Hewlett-Packard
Company in the United States and other countries. Other product
and company names mentioned herein may be trademarks of their
respective owners.

Version: PGP 8.0.2


Yours truly,
HP S/W Security Team
WTEC Cupertino, California


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