CVE-2025-27715

LOW

Mattermost 9.11.0-9.11.8 - Incorrect Authorization via Permalink

Title source: llm

Description

Mattermost versions 9.11.x <= 9.11.8 fail to prompt for explicit approval before adding a team admin to a private channel, which team admins to joining private channels via crafted permalink links without explicit consent from them.

References (1)

Core 1

Core References

Vendor Advisory

https://mattermost.com/security-updates

Scores

CVSS v3 3.3

EPSS 0.0017

EPSS Percentile 38.2%

Attack Vector NETWORK

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

CISA SSVC

Vulnrichment

Exploitation none

Automatable no

Technical Impact partial

Details

CWE

CWE-863

Status published

Products (2)

mattermost/mattermost 9.11.0 - 9.11.9Go

mattermost/mattermost_server 9.11.0 - 9.11.9

Published Mar 21, 2025

Tracked Since Feb 18, 2026