CVE-2026-7888

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. Thanks XananasX7 and Sanjorn Keeratirungsan (dizconnect) for both independently reporting. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 8.4 with vector 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.

CVSS

No CVSS.

References

Link	Resource
https://documentation.concretecms.org/9-x/developers/introduction/version-history/952-release-notes

Configurations

No configuration.

History

03 Jun 2026, 19:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-03 19:16

Updated : 2026-06-04 15:20

NVD link : CVE-2026-7888

Mitre link : CVE-2026-7888

CVE.ORG link : CVE-2026-7888

JSON object : View

Products Affected

No product.

CWE

CWE-502

Deserialization of Untrusted Data

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