Skip to content
OpenAdvisories
High · 8.9 CVE-2026-3452 EUVD-2026-9356GHSA-gj26-w59c-29mf

Concrete CMS below 9.4.8 is vulnerable to stored deserialization leading to RCE in the Express Entry List block.

Published Mar 4, 2026 · Updated Mar 4, 2026 · Assigned by ConcreteCMS

Description

Concrete CMS below version 9.4.8 is vulnerable to Remote Code Execution by stored PHP object injection into the Express Entry List block via the columns parameter. An authenticated administrator can store attacker-controlled serialized data in block configuration fields that are later passed to unserialize() without class restrictions or integrity checks. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 8.9 with vector CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H. Thanks YJK ( @YJK0805 https://hackerone.com/yjk0805 ) of ZUSO ART https://zuso.ai/  for reporting.

Affected products

VendorProductAffectedFixed
Concrete CMS Concrete CMS — —

Affected packages

EcosystemPackageAffectedFixedRecord
Packagist concrete5/concrete5 < 9.4.8 9.4.8 GHSA-gj26-w59c-29mf

References