CVE-2026-8434: Concrete CMS 9 before 9.5.0 is vulnerable to Cross Site Request Forgery (CSRF) at concrete/controllers/backend/file rescanMultiple()

Published May 21, 2026
·
Updated

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

2 affected components
Concrete CMS Concrete CMS 9<9.5.0
ConcreteCMS Concrete CMS>=9.0.0<9.5.1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Concrete CMS to a version that resolves this vulnerability.

    Fixed in 9.5.0

Event History

May 21, 2026
CVE Published
via MITRE·09:23 PM
Data Sourced
via MITRE·09:23 PM
DescriptionWeakness
Data Sourced
via NVD·10:16 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the risk assessment of CVE-2026-8434?

CVE-2026-8434 has a low severity rating of 2.3 according to the CVSS v4.0 scoring system.

2

What type of vulnerability is CVE-2026-8434?

CVE-2026-8434 is a Cross Site Request Forgery (CSRF) vulnerability affecting Concrete CMS 9 before version 9.5.0.

3

How does CVE-2026-8434 affect Concrete CMS?

CVE-2026-8434 can potentially allow an attacker to execute unauthorized actions on behalf of an authenticated user in Concrete CMS.

4

Is there a fix for CVE-2026-8434?

To resolve CVE-2026-8434, users should upgrade their Concrete CMS to version 9.5.0 or later.

5

When was CVE-2026-8434 published?

CVE-2026-8434 was published on May 21, 2026.

Contact

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