What is CVE-2026-8134?

CVE-2026-8134 is a high-severity vulnerability in Concrete Cms, classified under Relative Path Traversal. CVSS score: 7.2/10. Published 2026-05-21.

How severe is CVE-2026-8134?

High severity. CVSS v3 base score is 7.2 out of 10.

Path Traversal in Concrete Cms

CVE-2026-8134

Concrete CMS 9.5.0 and below fails to sanitize path traversal sequences in the ptComposerFormLayoutSetControlCustomTemplate field when saving page type composer form layouts. An authenticated rogue administrator with composer form editing…

EPSS: 0.005 (67.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.

Affected products

Concrete Cms — versions 5.0
Concretecms Concrete_cms

Weakness classification (CWE)

CWE-23 — Relative Path Traversal
CWE-98 — PHP Remote File Inclusion
CWE-434 — Unrestricted Upload of File with Dangerous Type

References

ff5b8ace-8b95-4078-9743-eac1ca5451de (release-notes, Release Notes)

Frequently asked questions

What is CVE-2026-8134?: CVE-2026-8134 is a high-severity vulnerability in Concrete Cms, classified under Relative Path Traversal. CVSS score: 7.2/10. Published 2026-05-21.
How severe is CVE-2026-8134?: High severity. CVSS v3 base score is 7.2 out of 10.