VULNERABILITY INTELLIGENCE
CVE-2026-8134
CVSS score7.2 HIGH
EPSS probability0.74%
CISA KEVNot currently listed
Published2026-05-21
Last modified2026-07-23
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Description
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 rights can exploit this to include arbitrary readable files on the server. Combined with the file uploader's extension-only validation (which permits PHP code in files saved with image extensions like .png), this can result in authenticated remote code execution. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 9.4 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H Thanks Yonatan Drori (Tenzai) for reporting.
Weakness classification
- ff5b8ace-8b95-4078-9743-eac1ca5451de: CWE-23
Primary references
- ff5b8ace-8b95-4078-9743-eac1ca5451de — Release Notes