CVE-2026-3452
Published:March 04, 2026
Updated:June 27, 2026
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 Packages
https://github.com/concretecms/concretecms.git (GITHUB):
Affected version(s) =9.5.0RC1 <9.5.0RC2Fix Suggestion:
Update to version 9.5.0RC2https://github.com/concretecms/concretecms.git (GITHUB):
Affected version(s) >=9.4.0RC1 <9.4.8Fix Suggestion:
Update to version 9.4.8concrete5/concrete5 (PHP):
Affected version(s) >=dev-allow-install-php-8.2 <9.4.8Fix Suggestion:
Update to version 9.4.8Related Resources (5)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.9
Attack Vector
NETWORK
Attack Complexity
HIGH
Attack Requirements
PRESENT
Privileges Required
HIGH
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
HIGH
Subsequent System Integrity
HIGH
Subsequent System Availability
HIGH
CVSS v3
Base Score:
8
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
HIGH
User Interaction
NONE
Scope
CHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Weakness Type (CWE)
Deserialization of Untrusted Data
EPSS
Base Score:
0.60