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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service
CVSS Vector v4.0
Weakness Type (CWE)
References 7
https://github.com/Cotonti/Cotonti
disclosure@vulncheck.com
https://github.com/Cotonti/Cotonti/blob/1.0.0/plugins/comments/comments.setup.p…
disclosure@vulncheck.com
https://github.com/Cotonti/Cotonti/blob/1.0.0/plugins/comments/controllers/acti…
disclosure@vulncheck.com
https://github.com/Cotonti/Cotonti/blob/1.0.0/plugins/comments/inc/CommentsWidg…
disclosure@vulncheck.com
https://github.com/Cotonti/Cotonti/issues/1888
disclosure@vulncheck.com
https://github.com/Cotonti/Cotonti/pull/1889
disclosure@vulncheck.com
https://www.vulncheck.com/advisories/cotonti-1.0.0-comments-plugin-php-object-i…
disclosure@vulncheck.com