Re: PHP Security Advisory: Vulnerability in PHP versions 4.2.0 and 4.2.1

Is there anything we could use with say mod_rewrite or snort, that could detect and avert a possible attack? I'm not sure I can upgrade all my installations, in due time, because of backwards compatibility issues in some extensions. Relating to that: how's the status on script-kiddie compatible exploits or an expected ATA on those? At 16:49 7/22/2002 +0300, Marko Karppinen wrote:

PHP Security Advisory: Vulnerability in PHP versions 4.2.0 and 4.2.1 Issued on: July 22, 2002 Software: PHP versions 4.2.0 and 4.2.1 Platforms: All The PHP Group has learned of a serious security vulnerability in PHP versions 4.2.0 and 4.2.1. An intruder may be able to execute arbitrary code with the privileges of the web server. This vulnerability may be exploited to compromise the web server and, under certain conditions, to gain privileged access. Description PHP contains code for intelligently parsing the headers of HTTP POST requests. The code is used to differentiate between variables and files sent by the user agent in a "multipart/form-data" request. This parser has insufficient input checking, leading to the vulnerability. The vulnerability is exploitable by anyone who can send HTTP POST requests to an affected web server. Both local and remote users, even from behind firewalls, may be able to gain privileged access. Impact Both local and remote users may exploit this vulnerability to compromise the web server and, under certain conditions, to gain privileged access. So far only the IA32 platform has been verified to be safe from the execution of arbitrary code. The vulnerability can still be used on IA32 to crash PHP and, in most cases, the web server. Solution The PHP Group has released a new PHP version, 4.2.2, which incorporates a fix for the vulnerability. All users of affected PHP versions are encouraged to upgrade to this latest version. The downloads web site at

      http://www.php.net/downloads.php

has the new 4.2.2 source tarballs, Windows binaries and source patches from 4.2.0 and 4.2.1 available for download. Workaround 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. Credits The PHP Group would like to thank Stefan Esser of e-matters GmbH for discovering this vulnerability. Copyright (c) 2002 The PHP Group. -- PHP Development Mailing List <http://www.php.net/> To unsubscribe, visit: http://www.php.net/unsub.php

Met vriendelijke groeten / With kind regards, Webmaster IDG.nl Melvyn Sopacua <@Logan> I spent a minute looking at my own code by accident. <@Logan> I was thinking "What the hell is this guy doing?" http://www.geekissues.org/quotes/top50.html?6824