SSRT4717 rev.1 Remote denial of service in Apache HTTP Server

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SSRT4717 rev.1 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:    14 July 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.
 HP-UX B.11.00, B.11.11, B.11.22, and B.11.23 running the
 hpuxwsAPACHE HP-UX Apache-based Web Server.


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).


     Note: To determine if a system has an affected version,
           search the output of "swlist -a revision -l fileset"
           for an affected fileset.  Then determine if the
           recommended patch or update is installed.

      For IPv4:
      HP-UX B.11.00
      HP-UX B.11.11
      action: install revision A. or subsequent

      HP-UX B.11.22
      action: migrate to B.11.23

      For IPv6:
      HP-UX B.11.11
      action: install revision B. or subsequent

      HP-UX B.11.23
      action: install revision B. or subsequent


Note: 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.
      Please write to for more information.

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

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 hpuxwsAPACHE: /opt/hpws/apache[32]/bin/apachectl stop

Download and Install Apache

- -----------------------------

- - Download Apache from Software Depot:

- - Verify successful download by comparing the cksum with the value
  specified on the installation web page.

- - Use SD to swinstall the depot.

   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 prefer to remove Apache from your system instead of
installing 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.

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



MANUAL ACTIONS:  Yes - NonUpdate
 Install the recommended product.
Revision 0 - 25 April 2004
  Initial release.
Revision 1 - 14 July 2004
  Corrected the affected versions in the Background section.

                      Note: Several Apache security bulletins
                      are being revised to correct the affected
                      versions specification to work correctly
                      with Security Patch Check revision B.02.00.

* 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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"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
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(c)Copyright 2004 Hewlett-Packard Development Company, L.P.
Hewlett-Packard Company shall not be liable for technical or
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Version: PGP 8.0.2


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


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