CVE-2026-93869

Cotonti through 1.0.0 contains an open redirect vulnerability in the cot_url_check() function that validates redirect destinations using a regular expression lacking an end-of-string anchor. Attackers can bypass the redirect guard by supplying hostnames beginning with the site domain to redirect users to attacker-controlled hosts through the ratings plugin or other redirect callers.

• https://github.com/Cotonti/Cotonti
• https://github.com/Cotonti/Cotonti/blob/1.0.0/plugins/ratings/ratings.ajax.php
• https://github.com/Cotonti/Cotonti/blob/1.0.0/system/functions.php
• https://github.com/Cotonti/Cotonti/issues/1891
• https://github.com/Cotonti/Cotonti/pull/1899
• https://www.vulncheck.com/advisories/cotonti-through-1.0.0-open-redirect-via-unanchored-cot-url-check-regex
• https://github.com/Cotonti/Cotonti/issues/1891