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—
Product
Concretecms 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
| Product | Affected versions | Fixed in |
|---|---|---|
| concretecms concrete_cms | 9.0 ≤ v < 9.5.1 | 9.5.1 |
| concrete5/concrete5Packagist | 9.0.0RC1 ≤ v < 9.5.1 | 9.5.1 |
Check your version
Choose the product and enter the version you run to see whether it falls in the affected range.
In the Intelligence 360 plan
Attack Surface Management
See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.