---
cve: "CVE-2026-22880"
severity: "MEDIUM"
cvss: 6.1
epss: "12%"
vendor: "Mattermost"
kev: false
exploited: false
published: "2026-05-21 09:16:26"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-12T22:44:04+02:00"
---

# CVE-2026-22880

> 6.1 MEDIUM

## Beschreibung

Mattermost Mobile Apps versions <=2.37 11.4 2.0.37 11.0.4 11.1.3 11.3.2 10.11.11.0 fail to properly validate the SSO authentication callback origin which allows an attacker controlling a malicious Mattermost server to steal user credentials for a legitimate Mattermost server via relaying the SSO code exchange flow through the mobile application. Mattermost Advisory ID: MMSA-2025-00564

## CVSS-Vektor

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

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

## Patch verfügbar (OSV)

- 545b8e9a4bca07022b756d35a7cd46972b449c75 (Commit)

## Referenzen

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

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-22880) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_