CVE-2025-55070
Medium · 6.5Mattermost does not enforce MFA on WebSocket connections
CVSS
6.5
EPSS
0.3%
Published
Nov 14, 2025
CISA due date
—
The record
Mattermost versions < 11 fail to enforce multi-factor authentication on WebSocket connections which allows unauthenticated users to access sensitive information via WebSocket events.
Affected packages
| Ecosystem | Package | Introduced | Fixed |
|---|---|---|---|
| Go | github.com/mattermost/mattermost-server | 0 | 11.1.0 |
| Go | github.com/mattermost/mattermost-server | 0 | 11.1.0+incompatible |
| Go | github.com/mattermost/mattermost-server/v5 | 0 | No fix |
| Go | github.com/mattermost/mattermost-server/v6 | 0 | No fix |
| Go | github.com/mattermost/mattermost/server/v8 | 0 | 8.0.0-20250912063506-7d8b7b5e4a60 |
Related vulnerabilities
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