IPS Community Suite 4.1.12.3 PHP Code Injection
Posted on 09 July 2016
--------------------------------------------------------------------------- IPS Community Suite <= 4.1.12.3 Autoloaded PHP Code Injection Vulnerability --------------------------------------------------------------------------- [-] Software Link: https://invisionpower.com/ [-] Affected Versions: Version 4.1.12.3 and prior versions. [-] Vulnerability Description: The vulnerable code is located in the /applications/core/modules/front/system/content.php script: 38. $class = 'IPS\' . implode( '\', explode( '_', IPSRequest::i()->content_class ) ); 39. 40. if ( ! class_exists( $class ) or ! in_array( 'IPSContent', class_parents( $class ) ) ) 41. { 42. IPSOutput::i()->error( 'node_error', '2S226/2', 404, '' ); 43. } User input passed through the "content_class" request parameter is not properly sanitized before being used in a call to the "class_exists()" function at line 40. This could be exploited by unauthenticated attackers to inject and execute arbitrary PHP code leveraging the autoloading function defined into the /applications/cms/Application.php script: 171. if ( mb_substr( $class, 0, 14 ) === 'IPScmsFields' and is_numeric( mb_substr( $class, 14, 1 ) ) ) 172. { 173. $databaseId = mb_substr( $class, 14 ); 174. eval( "namespace IPS\cms; class Fields{$databaseId} extends Fields { public static $customDatabaseId [...] 175. } Successful exploitation of this vulnerability requires the application running on PHP before version 5.4.24 or 5.5.8. [-] Proof of Concept: http://[host]/[ips]/index.php?app=core&module=system&controller=content&do=find&content_class=cmsFields1{}phpinfo();/* [-] Solution: Update to version 4.1.13 or later. [-] Disclosure Timeline: [04/07/2016] - Vendor notified [05/07/2016] - Vulnerability fixed in version 4.1.13: https://invisionpower.com/release-notes/4113-r44/ [06/07/2016] - CVE number requested [06/07/2016] - CVE number assigned [07/07/2016] - Public disclosure [-] CVE Reference: The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2016-6174 to this vulnerability. [-] Credits: Vulnerability discovered by Egidio Romano. [-] Original Advisory: http://karmainsecurity.com/KIS-2016-11
