RHSA-2002:214 - Security Advisory

Topic

PHP versions up to and including 4.2.2 contain vulnerabilities in the mail()
function, allowing local script authors to bypass safe mode restrictions
and possibly allowing remote attackers to insert arbitrary mail headers or
content.

[Updated 13 Jan 2003]
Added fixed packages for the Itanium (IA64) architecture.

[Updated 06 Feb 2003]
Added fixed packages for Advanced Workstation 2.1

Description

PHP is an HTML-embedded scripting language commonly used with the Apache
HTTP server.

The mail function in PHP 4.x to 4.2.2 may allow local script authors to
bypass safe mode restrictions and modify command line arguments to the
MTA (such as sendmail) in the 5th argument to mail(), altering MTA
behavior and possibly executing arbitrary local commands.

The mail function in PHP 4.x to 4.2.2 does not filter ASCII control
characters from its arguments, which could allow remote attackers to
modify mail message content, including mail headers, and possibly use
PHP as a "spam proxy."

Script authors should note that all input data should be checked for
unsafe data by any PHP scripts which call functions such as mail().

Note that this PHP errata, as did RHSA-2002:129, enforces memory limits on
the size of the PHP process to prevent a badly generated script from
becoming a possible source for a denial of service attack. The default
process size is 8Mb, though you can adjust this as you deem necessary
through the php.ini directive memory_limit. For example, to change the
process memory limit to 4MB, add the following:

memory_limit 4194304

Important Note:
There are special instructions you should follow regarding your
/etc/php.ini configuration file in the "Solution" section below.

Solution

Note that the /etc/php.ini configuration file is not replaced or
overwritten. You should carefully review your configuration file and adapt
it to your server or service functions.

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

This update is available via Red Hat Network. To use Red Hat Network,
launch the Red Hat Update Agent with the following command:

up2date

This will start an interactive process that will result in the appropriate
RPMs being upgraded on your system.

Affected Products

• Red Hat Enterprise Linux Server 2 ia64
• Red Hat Enterprise Linux Workstation 2 ia64

Fixes

• BZ - 74494 - New PHP packages fix vulnerability in mail function

CVEs

• CVE-2002-0986
• CVE-2002-0985

References

(none)