CVE-2026-7888 (GCVE-0-2026-7888)

Vulnerability from cvelistv5 – Published: 2026-06-03 18:10 – Updated: 2026-06-03 19:07
VLAI?
Title
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.
Summary
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.
Severity ?
8.4 (High)
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
CWE
  • CWE-502 - Deserialization of untrusted data
Assigner
References
Impacted products
Vendor Product Version
Concrete CMS Concrete CMS Affected: 5.0 , < 9.5.2 (git)
Create a notification for this product.
Credits
XananasX7 Sanjorn Keeratirungsan (dizconnect)
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