CVE-2026-8427: Concrete CMS 9 before 9.5.0 is vulnerable to Cross Site Request Forgery (CSRF) at concrete/controllers/backend/file removeFavoriteFolder($id). The Concrete CMS…

PriorityP343high8.8CVSS 3.1

AVNACLPRNUIRSUCHIHAH

EPSS

0.13%

3.0th percentile

Concrete CMS 9 before 9.5.0 is vulnerable to Cross Site Request Forgery (CSRF) at concrete/controllers/backend/file removeFavoriteFolder($id). The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 2.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori (Tenzai) for reporting.

Affected

3 ranges

Vendor	Product	Version range	Fixed in
concrete5	concrete5	>= 9.0.0RC1 < 9.5.1	9.5.1
concrete_cms	concrete_cms	9.0 – 9.5.0	—
concretecms	concrete_cms	>= 9.0.0 < 9.5.1	9.5.1

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

nvdv4.02.3LOWCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

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