CVE-2026-3452Network attack vector

Authenticated code execution via serialized block fields

Published Mar 4, 2026 · Updated Mar 4, 2026

PHP object injection in Concrete CMS before 9.4.8 allows remote authenticated users to execute code through Express Entry List settings. The block controller saves attacker-controlled columns data and later passes the serialized value to unserialize() without class restrictions or integrity checks. Administrator access is required; successful exploitation runs code in the CMS server context and can compromise the hosted site.

CVSS severity8.9
High
EPSS probability0.60%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

PHP object injection in Concrete CMS before 9.4.8 allows remote authenticated users to execute code through Express Entry List settings. The block controller saves attacker-controlled columns data and later passes the serialized value to unserialize() without class restrictions or integrity checks. Administrator access is required; successful exploitation runs code in the CMS server context and can compromise the hosted site.

The record

CVE
CVE-2026-3452
Published
Mar 4, 2026
Updated
Mar 4, 2026
Vendor
Concrete CMS
Product
Concrete CMS
Classifications
CWE-502, T1190
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Mar 4, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 4, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=5 <9.4.8

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Concrete CMS · Concrete CMSversion=5 <9.4.8

Published CVSS scores

7.2NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
8.9ConcreteCMSCVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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