CVE-2026-68532 Overview
CVE-2026-68532 is a Cross-Site Request Forgery (CSRF) vulnerability [CWE-352] in Concrete CMS versions 9.0.0 and later. The dashboard group type controller fails to validate a CSRF token on its delete action. A remote unauthenticated attacker can trick an authenticated user who holds group type management permissions into deleting a custom group type. The Concrete CMS security team assigned this vulnerability a CVSS v4.0 base score of 2.3. The issue was reported by the researcher credited as riodrwn and addressed in the Concrete CMS 9.5.3 release.
Critical Impact
An attacker can delete custom group types belonging to a targeted Concrete CMS instance if a privileged administrator visits an attacker-controlled page while authenticated.
Affected Products
- Concrete CMS 9.0.0 and later releases prior to 9.5.3
- Concrete CMS dashboard group type controller component
- Installations exposing group type management to authenticated administrators
Discovery Timeline
- Vulnerability reported by riodrwn to the Concrete CMS security team
- Fix delivered in the Concrete CMS 9.5.3 release
- 2026-09-15 - CVE-2026-68532 published to NVD
- 2026-09-16 - Last updated in NVD database
Technical Details for CVE-2026-68532
Vulnerability Analysis
The flaw resides in the Concrete CMS dashboard controller that handles custom group types. The delete action accepts state-changing requests without verifying an anti-CSRF token bound to the user's session. Because the server trusts the browser-supplied session cookie alone, any cross-origin request issued while the administrator is authenticated succeeds. An attacker hosting a malicious page or crafted email link can trigger the deletion by embedding an auto-submitting form or image tag that targets the vulnerable endpoint.
Exploitation requires an authenticated victim with group type management permission and some user interaction, such as clicking a link or loading a page. The impact is limited to integrity of application data: custom group types can be removed, which may disrupt group hierarchy assignments and downstream permission logic. No confidentiality loss or availability impact is reported.
Root Cause
The root cause is missing CSRF token validation on a state-changing HTTP request handler [CWE-352]. Concrete CMS provides a token framework, but the group type delete action did not enforce it. Requests were authorized based solely on the session cookie automatically attached by the browser.
Attack Vector
The attack vector is network-based and cross-origin. An attacker crafts an HTML page containing a form or request that targets the Concrete CMS delete endpoint for a specific group type identifier. When an authenticated administrator with group type management privileges loads the page, the browser transmits the request with valid session credentials, and the server executes the deletion. See the ConcreteCMS Version 9.5.3 Release Notes for the vendor's fix description.
Detection Methods for CVE-2026-68532
Indicators of Compromise
- Unexpected deletion events for custom group types recorded in the Concrete CMS activity or audit log
- HTTP POST or GET requests to the group type delete endpoint that originate from an external Referer header
- Administrator sessions performing dashboard actions immediately after navigating from an untrusted external domain
Detection Strategies
- Inspect web server access logs for requests targeting the dashboard group type controller delete route that lack expected CSRF token parameters
- Correlate administrator authentication sessions with subsequent group type deletion events to identify anomalous timing or referrer patterns
- Alert on cross-origin Referer values on state-changing dashboard endpoints
Monitoring Recommendations
- Forward Concrete CMS application logs and web server logs to a centralized log platform for retention and correlation
- Monitor privileged administrator account activity for unusual dashboard operations following external navigation events
- Track deletion events for group types and flag any deletions performed outside standard change windows
How to Mitigate CVE-2026-68532
Immediate Actions Required
- Upgrade all Concrete CMS instances to version 9.5.3 or later where the CSRF token check is enforced
- Audit accounts with group type management permission and remove the privilege from users who do not require it
- Instruct administrators to log out of Concrete CMS sessions when not actively using the dashboard
Patch Information
Concrete CMS addressed the missing CSRF validation in version 9.5.3. Details are published in the ConcreteCMS Version 9.5.3 Release Notes. Administrators should apply the vendor update through their standard Concrete CMS upgrade procedure and validate that the group type delete action requires a valid session token after patching.
Workarounds
- Restrict access to the Concrete CMS dashboard using network-level controls such as IP allowlists or VPN-only access until the patch is applied
- Configure a web application firewall rule to require a matching Origin or Referer header on requests to the group type delete endpoint
- Reduce the number of users assigned group type management permission to limit the exploitable surface
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
