---
cve: "CVE-2026-10542"
severity: "MEDIUM"
cvss: 5.0
epss: "0.1%"
vendor: "Mattermost"
kev: false
exploited: false
published: "2026-09-14 11:17:02"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-11-07T06:51:23+01:00"
---

# CVE-2026-10542

> 5.0 MEDIUM

## Beschreibung

Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7, 10.11.x <= 10.11.22 fail to validate channel action ownership which allows channel managers to update actions in other channels via the channel action update endpoint.. Mattermost Advisory ID: MMSA-2026-00692

## CNA-Record (Kanon, cvelistV5)

- CNA: **Mattermost**
- State: PUBLISHED
- Stand: 2026-09-14 11:19:45
- CNA-CVSS: **5.0** (`CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L`)

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **none**
  - Automatable: **no**
  - Technical Impact: **partial**

## CVSS-Vektor

```
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Hoch | good |
| PR Privilegien | Gering | warn |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Gering | warn |
| I Integrität | Gering | warn |
| A Verfügbarkeit | Gering | warn |

## Schwachstellen-Klasse

- **CWE-639** — Authorization Bypass Through User-Controlled Key
  The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.

## Patch verfügbar (OSV)

- 075d003e1391ff0b24eca1e63b0222eb46eaded6 (Commit)
- d42004bb3046de3ed176938a34b1a70c1c3d9421 (Commit)

## Referenzen

- <https://mattermost.com/security-updates>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2026-10542/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_