CVE-2026-7888
Concrete CMS is vulnerable to PHP Object Injection via unserialize() calls in the Workflow, Form block, and File/Set components
EPSS 0.18%
Description
Concrete CMS below 9.5.2 is vulnerable to PHP Object Injection via unserialize() calls in the Workflow, Form block, and File/Set components that lack the allowed_classes restriction. An unauthenticated attacker may trigger arbitrary PHP object instantiation if a malicious serialized payload has been placed in the database. The Concrete CMS security team thanks XananasX7 and Sanjorn Keeratirungsan (dizconnect) for both independently reporting this ssue.
How to fix CVE-2026-7888
To remediate CVE-2026-7888, upgrade the affected package to a fixed version below.
- —upgrade to 9.5.2 or later
Is CVE-2026-7888 being exploited?
Low — EPSS is 0.2%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 9.5.2
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |