---
cve: "CVE-2026-8417"
severity: "HIGH"
cvss: 7.5
epss: "12%"
vendor: "Concrete CMS"
kev: false
exploited: false
published: "2026-05-21 21:16:33"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-08T00:09:55+02:00"
---

# CVE-2026-8417

> 7.5 HIGH

## Beschreibung

Concrete CMS 9.5.0 and below does not validate a CSRF token before processing requests to /dashboard/extend/update/do_update/. The do_update() method in concrete/controllers/single_page/dashboard/extend/update.php checks only canInstallPackages() before executing upgradeCoreData() and upgrade() on the named package's controller. Because the endpoint is a state-changing GET route with no token enforcement, an attacker can force an authenticated administrator to trigger a package upgrade via a single cross-site navigation.In order to be vulnerable, the victim must be passing canInstallPackages() and and a target package must already be already installed. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 7.5 with 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. Thanks  https://github.com/maru1009  for reporting.

## CVSS-Vektor

```
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
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Hoch | good |
| PR Privilegien | Keine | bad |

## Patch verfügbar (OSV)

- 92bae566b9ec573cfb3017fcbb6db454a6586997 (Commit)

## Referenzen

- <https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-8417) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_