Vulnerability details
CVE-2026-91939
Cotonti Cotonti
Cotonti 1.0.0 Comments Plugin PHP Object Injection via ci Parameter
CVSS 4.0
9.3Critical
Official description
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.
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 9.3Critical | 4.0 | CVEProject cvelistV5 (CNA) (VulnCheck) | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
| 9.8Critical | 3.1 | CVEProject cvelistV5 (CNA) (VulnCheck) | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| Cotonti | Cotonti | 1.0.0 ≤ v ≤ 1.0.0 | CVEProject cvelistV5 (CNA) |
References and advisories
7- https://github.com/Cotonti/Cotonti/pull/1889 patchissue-tracking
- https://github.com/Cotonti/Cotonti/blob/1.0.0/plugins/comments/inc/CommentsWidget.php technical-description
- https://github.com/Cotonti/Cotonti/blob/1.0.0/plugins/comments/controllers/actions/DisplayAction.php technical-description
- https://github.com/Cotonti/Cotonti/blob/1.0.0/plugins/comments/comments.setup.php technical-description
- https://github.com/Cotonti/Cotonti product
- https://www.vulncheck.com/advisories/cotonti-1.0.0-comments-plugin-php-object-injection-via-ci-parameter third-party-advisory
- https://github.com/Cotonti/Cotonti/issues/1888 issue-tracking
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Details
- Published
- 2026-09-16
- Last updated
- 2026-09-24
- State
- Published
- Assigner (CNA)
- VulnCheck
Exploit prediction (EPSS)
0.97%
Probability of exploitation in 30 days
62.3%
Percentile (among all CVEs)
SSVC assessment (CISA)
- Automatable
- Yes
- Exploitation
- Proof of concept
- Technical impact
- Total
Weaknesses (CWE)
- CWE-502Deserialization of Untrusted Data