Cotonti 1.0.0 passes the base64-decoded cb parameter to unserialize() without allowed_classes restriction in the comments plugin EditAction. Registered users with comment write permissions can instantiate arbitrary PHP objects and potentially achieve file write or code execution through gadget chains.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
High
Difficult to exploit
Attack Requirements
Present
Additional conditions required
Privileges Required
Low
Basic 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 6
https://github.com/Cotonti/Cotonti
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/system/cache.php
disclosure@vulncheck.com
https://github.com/Cotonti/Cotonti/issues/1894
disclosure@vulncheck.com
https://github.com/Cotonti/Cotonti/pull/1897
disclosure@vulncheck.com
https://www.vulncheck.com/advisories/cotonti-1.0.0-php-object-injection-via-com…
disclosure@vulncheck.com