CVE-2026-91939
CRITICALCVSS 9.8Description
Cotonti 1.0.0 Comments plugin passes the ci GET parameter to unserialize() without allowed_classes restriction, allowing unauthenticated attackers to instantiate arbitrary PHP classes with attacker-controlled properties. Attackers can exploit PHP object injection through crafted serialized payloads to trigger gadget chains and achieve database manipulation or code execution.
Timeline
Published:September 15th, 2026 9:16 PM
Last modified:September 16th, 2026 8:21 PM
CVSS Scoring
CVSS v3: 9.8 (CRITICAL)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weaknesses (CWE)
References & Reports
Advisories, patches, and third-party reports
- https://github.com/Cotonti/Cotonti
- https://github.com/Cotonti/Cotonti/blob/1.0.0/plugins/comments/comments.setup.php
- https://github.com/Cotonti/Cotonti/blob/1.0.0/plugins/comments/controllers/actions/DisplayAction.php
- https://github.com/Cotonti/Cotonti/blob/1.0.0/plugins/comments/inc/CommentsWidget.php
- https://github.com/Cotonti/Cotonti/issues/1888
- https://github.com/Cotonti/Cotonti/pull/1889
- https://www.vulncheck.com/advisories/cotonti-1.0.0-comments-plugin-php-object-injection-via-ci-parameter
- https://github.com/Cotonti/Cotonti/issues/1888
Source: NIST NVD · Data may lag official sources by up to one minute