Concrete CMS is Vulnerable to Cross-Site Request Forgery
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 canInstallPackages() permission before fetching a remote marketplace package and writing it to the server's DIR_PACKAGES directory. Because the endpoint is a state-changing GET route with no token enforcement, an attacker who can cause an authenticated administrator to visit a crafted page can force an arbitrary marketplace package to be downloaded. In order to be vulnerable, the victim must be passing canInstallPackages() and the site must be connected to the Concrete marketplace. Concrete CMS thanks https://github.com/maru1009 for reporting this issue.
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Composer package | concrete5/concrete5 | < 9.5.1 | 9.5.1 |
References
- CVSS vector
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N- Weakness (CWE)
CWE-352- Platform
- Composer
- Package
concrete5/concrete5- Disclosed
- 21.05.2026
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-r42c-3rr2-jrfp - CC BY 4.0
Vulnerability history: concrete5/concrete5
All published vulnerabilities of this package (Composer package), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 121
- First → latest
- 10.2021 06.2026
- Without a fix
- 10
- Exploited in attacks
- 0
Severity breakdown
- Critical 2
- High 16
- Medium 65
- Low 38
Disclosures per year
- 2021: 2
- 2022: 18
- 2023: 21
- 2024: 21
- 2025: 5
- 2026: 54
-
Concrete CMS is Vulnerable to Cross-Site Request Forgery this entry
Know which vulnerabilities affect your application
With the DockRay integration and software inventory enabled, DockRay checks reported component versions against known vulnerabilities and notifies you about confirmed matches. Coverage depends on the supported technology and available advisory data.