by Kastro
Paper/Archive/CVE-2026-91939

CVE-2026-91939

Cotonti Cotonti — Cotonti 1.0.0 Comments Plugin PHP Object Injection via ci Parameter

EPSS 1.0%public exploitCVSS 9.8
critical.is priorityof 100
52
CVSS 9.8 (CNA)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 62.2.622 × 2012.4Exploit: SSVC poc+1010.0SSVC exploitation: poc+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
Cotonti1.0.0 – 1.0.0–CNA

Scores by source

VulnCheck (CNA)9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
VulnCheck (CNA)9.3CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CISA ADPSSVCExploitation: poc · Automatable: yes · Technical impact: total

References

exploitgithub.com/Cotonti/Cotonti/issues/1888patchgithub.com/Cotonti/Cotonti/pull/1889writeupgithub.com/Cotonti/Cotonti/blob/1.0.0/plugins/comments/inc/CommentsWidget.phpwriteupgithub.com/Cotonti/Cotonti/blob/1.0.0/plugins/comments/controllers/actions/DisplayAction.phpwriteupgithub.com/Cotonti/Cotonti/blob/1.0.0/plugins/comments/comments.setup.phprefgithub.com/Cotonti/Cotontiwriteupvulncheck.com/advisories/cotonti-1.0.0-comments-plugin-php-object-injection-via-ci-parameter