CVE-2026-8435

Medium

Description

Concrete CMS 9 before 9.5.0 is vulnerable to Cross Site Request Forgery (CSRF) at concrete/controllers/backend/file approveVersion(). 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.

SeverityMedium
CVSS6.5
Exploit probability—
ProductConcretecms Concrete Cms
PublishedMay 21, 2026
First seenMay 21, 2026

How to fix

Update
  • concretecms concrete_cms9.5.1 or later
  • concrete5/concrete59.5.1 or later

Affected products

ProductAffected versionsFixed in
concretecms concrete_cms9.0 ≤ v < 9.5.19.5.1
concrete5/concrete5Packagist9.0.0RC1 ≤ v < 9.5.19.5.1

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