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CERT Coordination Center

PHP fails to properly parse the headers of HTTP POST requests

Vulnerability Note VU#929115

Original Release Date: 2002-07-22 | Last Revised: 2003-05-30

Overview

A vulnerability has been discovered in PHP. This vulnerability could be used by a remote attacker to execute arbitrary code or crash PHP and/or the web server.

Description

PHP is a popular scripting language in widespread use. For more information about PHP, see http://www.php.net/manual/en/faq.general.php.

The vulnerability occurs in the portion of PHP code responsible for handling file uploads, specifically multipart/form-data. By sending a specially crafted POST request to the web server, an attacker can corrupt the internal data structures used by PHP. Specifically, an intruder can cause an improperly initialized memory structure to be freed. In most cases, an intruder can use this flaw to crash PHP or the web server. Under some circumstances, an intruder may be able to take advantage of this flaw to execute arbitrary code with the privileges of the web server.

You may be aware that freeing memory at inappropriate times in some implementations of malloc and free does not usually result in the execution of arbitrary code. However, because PHP utilizes its own memory management system, the implementation of malloc and free is irrelevant to this problem.

Stefan Esser of e-matters GmbH has indicated that intruders cannot execute code on x86 systems. However, we encourage system administrators to apply patches on x86 systems as well to guard against denial-of-service attacks and as-yet-unknown attack techniques that may permit the execution of code on x86 architectures.

This vulnerability was discovered by e-matters GmbH and is described in detail in their advisory. The PHP Group has also issued an advisory. A list of vendors contacted by the CERT/CC and their status regarding this vulnerability is available in VU#929115.

Although this vulnerability only affects PHP 4.2.0 and 4.2.1, e-matters GmbH has previously identified vulnerabilities in older versions of PHP. If you are running older versions of PHP, we encourage you to review http://security.e-matters.de/advisories/012002.html.

Impact

A remote attacker can execute arbitrary code on a vulnerable system. An attacker may not be able to execute code on x86 architectures due to the way the stack is structured. However, an attacker can leverage this vulnerability to crash PHP and/or the web server running on an x86 architecture.

Solution

Apply a patch from your vendor

Appendix A contains information provided by vendors for this advisory. As vendors report new information to the CERT/CC, we will update this section and note the changes in our revision history. If a particular vendor is not listed below, we have not received their comments. Please contact your vendor directly.

Upgrade to the latest version of PHP

If a patch is not available from your vendor, upgrade to version 4.2.2.

Deny POST requests

Until patches or an update can be applied, you may wish to deny POST requests. The following workaround is taken from the PHP Security Advisory:

      If the PHP applications on an affected web server do not rely on HTTP POST input from user agents, it is often possible to deny POST requests on the web server.

      In the Apache web server, for example, this is possible with the following code included in the main configuration file or a top-level .htaccess file:

      <Limit POST>
         Order deny,allow
         Deny from all
      </Limit>

      Note that an existing configuration and/or .htaccess file may have parameters contradicting the example given above.

Disable vulnerable service

Until you can upgrade or apply patches, you may wish to disable PHP. As a best practice, the CERT/CC recommends disabling all services that are not explicitly required. Before deciding to disable PHP, carefully consider your service requirements.

Vendor Information

929115
 
Affected   Unknown   Unaffected

Debian

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Vulnerable

Vendor Statement

Debian GNU/Linux stable aka 3.0 is not vulnerable.

Debian GNU/Linux testing is not vulnerable.
Debian GNU/Linux unstable is vulnerable.

The problem effects PHP versions 4.2.0 and 4.2.1. Woody ships an older version of PHP (4.1.2), that doesn't contain the vulnerable function.

Vendor Information

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

Addendum

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.

FreeBSD

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Vulnerable

Vendor Statement

FreeBSD does not include any version of PHP by default, and so is not vulnerable; however, the FreeBSD Ports Collection does contain the PHP4 package. Updates to the PHP4 package are in progress and a corrected package will be available in the near future.

Vendor Information

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

Addendum

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.

MandrakeSoft

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Vulnerable

Vendor Statement

Mandrake Linux does not ship with PHP version 4.2.x and as such is not vulnerable. The Mandrake Linux cooker does currently contain PHP 4.2.1 and will be updated shortly, but cooker should not be used in a production environment and no advisory will be issued.

Vendor Information

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

Addendum

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.

PHP Development Team

Updated:  July 22, 2002

Status

  Vulnerable

Vendor Statement

See http://www.php.net/release_4_2_2.php.

Vendor Information

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

Addendum

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.

Apple Computer Inc.

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Not Vulnerable

Vendor Statement

Mac OS X and Mac OS X Server are shipping with PHP version 4.1.2 which does not contain the vulnerability described in this alert.

Vendor Information

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

Addendum

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.

Conectiva

Updated:  July 23, 2002

Status

  Not Vulnerable

Vendor Statement

PHP 4.2.x is not shipped with Conectiva Linux.

Vendor Information

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

Addendum

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.

Cray Inc.

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Not Vulnerable

Vendor Statement

Cray, Inc. does not supply PHP on any of its systems.

Vendor Information

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

Addendum

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.

F5 Networks

Notified:  July 22, 2002 Updated:  July 23, 2002

Status

  Not Vulnerable

Vendor Statement

F5 Networks products do not include PHP 4.2.0 or 4.2.1, and are therefore not affected by this vulnerability.

Vendor Information

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

Addendum

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.

Guardian Digital Inc.

Updated:  July 22, 2002

Status

  Not Vulnerable

Vendor Statement

Guardian Digital has not shipped PHP 4.2.x in any versions of EnGarde, therefore we are not believed to be vulnerable at this time.

Vendor Information

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

Addendum

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.

Hewlett-Packard Company

Notified:  July 22, 2002 Updated:  July 25, 2002

Status

  Not Vulnerable

Vendor Statement

We have verified that this problem is not present on our distributions for HP Tru64 UNIX or HP OpenVMS products.

Vendor Information

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

Addendum

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.

IBM

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Not Vulnerable

Vendor Statement

IBM is not vulnerable to the above vulnerabilities in PHP. We do supply the PHP packages for AIX through the AIX Toolbox for Linux Applications. However, these packages are at 4.0.6 and also incorporate the security patch from 2/27/2002.

Vendor Information

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

Addendum

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.

Microsoft Corporation

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Not Vulnerable

Vendor Statement

Microsoft products are not affected by the issues detailed in this advisory.

Vendor Information

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

Addendum

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.

Network Appliance

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Not Vulnerable

Vendor Statement

No Netapp products are vulnerable to this.

Vendor Information

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

Addendum

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.

Red Hat Inc.

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Not Vulnerable

Vendor Statement

None of our commercial releases ship with vulnerable versions of PHP (4.2.0, 4.2.1).

Vendor Information

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

Addendum

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.

SuSE Inc.

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Not Vulnerable

Vendor Statement

SuSE Linux is not vulnerable to this problem, as we do not ship PHP 4.2.x.

Vendor Information

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

Addendum

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.

The SCO Group (SCO Linux)

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Not Vulnerable

Vendor Statement

Caldera OpenLinux does not provide either vulnerable version (4.2.0, 4.2.1) of PHP in their products. Therefore, Caldera products are not vulnerable to this issue.

Vendor Information

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

Addendum

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.

Trustix

Updated:  July 24, 2002

Status

  Not Vulnerable

Vendor Statement

The TSL team states that none of the versions of the Trustix Secure Linux distribution is vulnerable to the php 4.2.{0,1} vulnerability (CA-2002-21) as none of the TSL versions is shipped with php 4.2.x.

Vendor Information

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

Addendum

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.

Xerox Corporation

Notified:  July 22, 2002 Updated:  May 30, 2003

Status

  Not Vulnerable

Vendor Statement

A response to this vulnerability is available from our web site: http://www.xerox.com/security.

Vendor Information

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

Addendum

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.

3Com

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

AT&T

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Alcatel

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

BSDI

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Cisco Systems Inc.

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Compaq Computer Corporation

Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

SOURCE: Compaq Computer Corporation, a wholly-owned subsidiary of Hewlett-Packard Company and Hewlett-Packard Company HP Services Software Security Response Team

x-ref: SSRT2300 php post requests

At the time of writing this document, Compaq is currently investigating the potential impact to Compaq's released Operating System software products.

As further information becomes available Compaq will provide notice of the availability of any necessary patches through standard security bulletin announcements and be available from your normal HP Services supportchannel.

Vendor Information

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

Addendum

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.

Computer Associates

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Data General

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Fujitsu

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Guardian Digital Inc.

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Intel

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Juniper Networks

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Lachman

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Lotus Software

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Lucent Technologies

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Multinet

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

NEC Corporation

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

NetBSD

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Nortel Networks

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

OpenBSD

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Oracle Corporation

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

SGI

Notified:  July 22, 2002 Updated:  July 24, 2002

Status

  Unknown

Vendor Statement

SGI acknowledges the PHP vulnerabilitity reported by CERT and is currently investigating. PHP does not currently ship as part of IRIX so SGI can confirm that base IRIX is not vulnerable. No further information is available at this time.

For the protection of all our customers, SGI does not disclose, discuss or confirm vulnerabilities until a full investigation has occurred and any necessary patch(es) or release streams are available for all vulnerable and supported IRIX operating systems. Until SGI has more definitive information to provide, customers are encouraged to assume all security vulnerabilities as exploitable and take appropriate steps according to local site security policies and requirements. As further information becomes available, additional advisories will be issued via the normal SGI security information distribution methods including the wiretap mailing list on http://www.sgi.com/support/security/.

Vendor Information

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

Addendum

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.

Sequent

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Sony Corporation

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Sun Microsystems Inc.

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Unisphere Networks

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Unisys

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.

Wind River Systems Inc.

Notified:  July 22, 2002 Updated:  July 22, 2002

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

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

Addendum

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.


CVSS Metrics

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A

References

Credit

Thanks to e-matters Security for reporting this vulnerability.

This document was written by Ian A Finlay.

Other Information

CVE IDs: CVE-2002-0717
CERT Advisory: CA-2002-21
Severity Metric: 42.53
Date Public: 2002-07-22
Date First Published: 2002-07-22
Date Last Updated: 2003-05-30 17:21 UTC
Document Revision: 35

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