Digital Security Research Group [DSecRG] Advisory #DSECRG-08-008 Application: Txp CMS Versions Affected: 4.0.5 Vendor URL: http://www.textpattern.com Bugs: DOS, multiple XSS, etc. Exploits: YES Reported: 11.01.2008 Vendor response: 14.01.2008 Patch Released: 03.02.2008 Date of Public Advisory: 04.02.2008 Authors: Alexandr Polyakov, Stas Svistunovich Digital Security Research Group [DSecRG] (research [at] dsec [dot] ru) Description *********** Textpattern system has multiple security vulnerabilities: 1. Parameter Value Overflow 2. Linked XSS 3. XSS in POST 4. Stored XSS 5. Insecure password changing algorithm Details ******* 1. Parameter Value Overflow Vulnerability found in script index.php in comments section. Post parameter "message". The application does not ensure that the parameter value length. It can be used for performing a DOS attack. Example: message = [A]x10000 ------------------------------------------------------------------------ -------------------- 2. Linked XSS vulnerability found in /textpattern/setup/index.php, attacker can inject XSS in URL string. Example: http://[server]/[installdir]/textpattern/setup/index.php/"><script>alert ('DSecRG XSS')</script> ------------------------------------------------------------------------ -------------------- 3. XSS in POST Vulnerability found in script index.php in comments section. Post parameter "name". Example: name = <img src="javascript:alert('DSecRG XSS')"> name = <script>alert('DSecRG XSS')</script> ------------------------------------------------------------------------ -------------------- 4. Stored XSS Vulnerability found in script textpattern/index.php?event=article in post parameter "Body". Example: Body = <IMG SRC=javascript:alert("DSecRG_XSS")> ------------------------------------------------------------------------ -------------------- 5. Insecure password changing algorithm Previous password not required to set a new password. If attacker gain access to admin session by using XSS vulnerability, he can change admin password without knowing old password. It will be more secure to ask old password when changing password or primary email. Fix Information *************** Textpattern was altered to fix this flaw on 03.02.2008. Updated version (4.0.6) can be downloaded here: http://textpattern.com/download About ***** Digital Security is leading IT security company in Russia, providing information security consulting, audit and penetration testing services, risk analysis and ISMS-related services and certification for ISO/IEC 27001:2005 and PCI DSS standards. Digital Security Research Group focuses on web application and database security problems with vulnerability reports, advisories and whitepapers posted regularly on our website. Contact: research [at] dsec [dot] ru http://www.dsec.ru (in Russian) -- Digital Security Research Group mailto:research (at) dsec (dot) ru [email concealed]