CVE-2026-91939

Cotonti 1.0.0 Comments Plugin PHP Object Injection via ci Parameter

Published Sep 15, 2026 CVSS 4.0 · 9.3 Critical EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Cotonti cotonti
Cotonti siena
Vendors & Products Cotonti cotonti
Cotonti siena
Type Values Removed Values Added
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.
Title Cotonti 1.0.0 Comments Plugin PHP Object Injection via ci Parameter
First Time appeared Cotonti
Cotonti cotonti Siena
Weaknesses CWE-502
CPEs cpe:2.3:a:cotonti:cotonti_siena:*:*:*:*:*:*:*:*
Vendors & Products Cotonti
Cotonti cotonti Siena
References
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

cvssV4_0

{'score': 9.3, 'vector': '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'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Sep 24, 2026, 2:22 PM
Reserved
Sep 15, 2026, 11:07 AM
Status
Deferred
Published
Sep 15, 2026, 9:16 PM
Modified
Sep 16, 2026, 8:21 PM