Vulnerability · Published Sep 18, 2026 · Assigned by VulnCheck

CVE-2026-93869Cotonti through 1.0.0 Open Redirect via Unanchored cot_url_check() Regex

Medium 6.1

In plain English

A medium-severity open redirect in Cotonti from Cotonti. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 30% of all known vulnerabilities).

Severity (CVSS 3.1)6.1Medium

Exploit odds (30 days)0.4%top 70.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

Vendor	Product	Versions
Cotonti	Cotonti	0 – through 1.0.0

Weakness: CWE-601 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

References

https://github.com/Cotonti/Cotonti/issues/1891 issue-tracking
https://github.com/Cotonti/Cotonti/pull/1899 patch, issue-tracking
https://github.com/Cotonti/Cotonti/blob/1.0.0/system/functions.php technical-description
https://github.com/Cotonti/Cotonti/blob/1.0.0/plugins/ratings/ratings.ajax.php technical-description
https://github.com/Cotonti/Cotonti product
VulnCheck Advisory: Cotonti through 1.0.0 Open Redirect via Unanchored cot_url_check() Regex third-party-advisory