OneCMS 2.6 contains multiple flaws which can be exploited by malicious users to conduct script insertion attacks and by malicious people to conduct cross-site scripting and SQL injection attacks.

1) Input passed via the "[database prefix]_username" cookie (e.g. "oncecms_username") to admin/admin.php or through various scripts (e.g. admin/admin.php, admin/files.php, admin/settings.php) to config.php or functions.php and via the "cat" parameter to admin/admin.php is not properly sanitised before being used in SQL queries. This can be exploited to manipulate SQL queries by injecting arbitrary SQL code.

2) Input passed via the "cat" parameter to admin/admin.php and via the URL through various scripts (e.g. admin/admin.php, admin/ads.php, admin/affiliates.php, admin/comments.php) to functions.php is not properly sanitised before being returned to the user. This can be exploited to execute arbitrary HTML and script code in a user's browser session in context of an affected site.

References:

CVE-2010-pending

BID: 41194

OSVDB: 66194 66195 66197 66198 66199 66200 66201 66202 66203 66204 66205

SA: 39395

VUPEN: 1627

XF: 59851

Related: 

Vendor Solution: Upgrade to 2.6.2