CVE-2025-55070

MEDIUM

Mattermost <11 - Unauthenticated Information Disclosure via WebSocket Events

Title source: llm

Description

Mattermost versions <11 fail to enforce multi-factor authentication on WebSocket connections which allows unauthenticated users to access sensitive information via WebSocket events

References (1)

Core 1

Core References

Vendor Advisory

https://mattermost.com/security-updates

Scores

CVSS v3 6.5

EPSS 0.0015

EPSS Percentile 34.8%

Attack Vector NETWORK

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

CISA SSVC

Vulnrichment

Exploitation none

Automatable no

Technical Impact partial

Details

CWE

CWE-306

Status published

Products (3)

mattermost/mattermost 0 - 8.0.0-20250912063506-7d8b7b5e4a60Go

mattermost/mattermost-server 0 - 11.1.0Go

mattermost/mattermost_server < 11.0.0

Published Nov 14, 2025

Tracked Since Feb 18, 2026