CVE-2026-8347
Medium
Description
Concrete CMS 9.5.0 and below is vulnerable to IDOR + wrong-authorization-level in the Express association Reorder dialog. This can cause Cross-entity state tampering with view-only permission on one entry. To be affected, a website has to be using express and relying on express entity ordering. 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:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Winston Crooker for reporting.
SeverityMedium
CVSS4.3
Exploit probability—
Product
Concretecms Concrete Cms
PublishedMay 22, 2026
First seenMay 22, 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 | v < 9.5.1 | 9.5.1 |
| concrete5/concrete5Packagist | v < 9.5.1 | 9.5.1 |
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