What is CVE-2026-8140?

CVE-2026-8140 is a medium-severity vulnerability in Concrete Cms, classified under Cross-Site Request Forgery (CSRF). CVSS score: 6.5/10. Published 2026-05-21.

How severe is CVE-2026-8140?

Medium severity. CVSS v3 base score is 6.5 out of 10.

CSRF in Concrete Cms

CVE-2026-8140

Concrete CMS 9.5.0 and below does not validate a CSRF token before processing requests to /dashboard/extend/install/download/<remoteId>. The download() method in concrete/controllers/single_page/dashboard/extend/install.php checks only the…

Vulnerability class: CSRF (Cross-Site Request Forgery)

EPSS: 0.000 (4.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N.

Affected products

Concrete Cms — versions 5.0
Concretecms Concrete_cms

Weakness classification (CWE)

CWE-352 — Cross-Site Request Forgery (CSRF)

References

ff5b8ace-8b95-4078-9743-eac1ca5451de (release-notes, Release Notes)

Frequently asked questions

What is CVE-2026-8140?: CVE-2026-8140 is a medium-severity vulnerability in Concrete Cms, classified under Cross-Site Request Forgery (CSRF). CVSS score: 6.5/10. Published 2026-05-21.
How severe is CVE-2026-8140?: Medium severity. CVSS v3 base score is 6.5 out of 10.