PT-2025-23309 · Mattermost · Mattermost

Name of the Vulnerable Software and Affected Versions: Mattermost versions 10.7.x through 10.7.0 Mattermost versions 10.5.x through 10.5.3 Mattermost versions 9.11.x through 9.11.12 Description: The issue is related to the failure of Mattermost to properly enforce access control restrictions for...

Mattermost Fails to Verify User's Permissions When Accessing Groups

Mattermost versions 10.5.x = 10.5.2, 9.11.x = 9.11.11 failed to properly verify a user's permissions when accessing groups, which allows an attacker to view group information via an API request...

GHSA-QGWX-RFFP-6CX9 Mattermost Fails to Lockout LDAP Users After Repeated Login Failures

Mattermost versions 10.6.x = 10.6.1, 10.5.x = 10.5.2, 10.4.x = 10.4.4, 9.11.x = 9.11.11 fail to lockout LDAP users following repeated login failures, which allows attackers to lock external LDAP accounts through repeated login failures through Mattermost...

GHSA-WWHJ-PW6H-F8HW Mattermost Incorrect Authorization vulnerability

Mattermost versions 10.5.x = 10.5.1, 9.11.x = 9.11.9 fail to check if a file has been deleted when creating a bookmark which allows an attacker who knows the IDs of deleted files to obtain metadata of the files via bookmark creation...

Mattermost Fails to Restrict Certain Operations on System Admins

Mattermost versions 10.5.x = 10.5.1, 10.4.x = 10.4.3, 9.11.x = 9.11.9 fail to restrict certain operations on system admins to only other system admins, which allows delegated granular administration users with the "Edit Other Users" permission to perform unauthorized modifications to system...

BIT-MATTERMOST-2025-27715

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...

GHSA-CW7Q-5CGC-H3H9 Mattermost fail to prompt for explicit approval before adding a team admin to a private channel

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...

GHSA-3GPX-P63P-PR5R Mattermost Fails to Enforce Certain Search APIs

Mattermost versions 10.4.x = 10.4.2, 10.3.x = 10.3.3, 9.11.x = 9.11.8 fail to enforce MFA on certain search APIs, which allows authenticated attackers to bypass MFA protections via user search, channel search, or team search queries...

CVE-2025-27933

Mattermost versions 10.4.x = 10.4.2, 10.3.x = 10.3.3, 9.11.x = 9.11.8 fail to fail to enforce channel conversion restrictions, which allows members with permission to convert public channels to private ones to also convert private ones to public...

Mattermost allows reading arbitrary files

Mattermost versions 10.4.x = 10.4.1, 9.11.x = 9.11.7, 10.3.x = 10.3.2, 10.2.x = 10.2.2 fail to properly validate input when patching and duplicating a board, which allows a user to read any arbitrary file on the system via duplicating a specially crafted block in Boards...

GO-2025-3379 Mattermost Improper Validation of Specified Type of Input vulnerability in github.com/mattermost/mattermost-server

Mattermost Improper Validation of Specified Type of Input vulnerability in github.com/mattermost/mattermost-server. NOTE: The source advisory for this report contains additional versions that could not be automatically mapped to standard Go module versions. If this is causing false-positive repor...