CVE-2026-3452
highpriority · track · 29EPSS 0.006 · 50 %ileEUUSEPSS · scored 2026-10-26
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.9–8.9
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (3)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- GHSA-gj26-w59c-29mfConcrete CMS vulnerable to Remote Code Execution by stored PHP object injection2026-03-04ghsa · osvUS
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 thanks YJK ( @YJK0805 https://hackerone.com/yjk0805 ) of ZUSO ART https://zuso.ai/ for reporting.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (7)
External citations — patches, advisories, analysis.
- https://documentation.concretecms.org/9-x/developers/introduction/version-history/948-release-notescnnvd
- https://github.com/concretecms/concretecms/pull/12826/changes/167f16e4805d8ab546d2997c753ac21bf4854920://cnnvd
- https://www.concretecms.org/downloadPatchcnnvd
- https://documentation.concretecms.org/9-x/developers/introduction/version-history/948-release-notesenisa_euvd
- https://github.com/concretecms/concretecms/pull/12826/changes/167f16e4805d8ab546d2997c753ac21bf4854920://enisa_euvd
- https://documentation.concretecms.org/9-x/developers/introduction/version-history/948-release-notesPatchRelease NotesVendor Advisorynvd
- https://github.com/concretecms/concretecms/pull/12826/changes/167f16e4805d8ab546d2997c753ac21bf4854920://Broken Linknvd
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