Mattermost Server < 11.0.0 Multiple Vulnerabilities (MMSA-2024-00337, MMSA-2025-00493, MMSA-2025-00540)

The version of Mattermost Server installed on the remote host is affected by multiple vulnerabilities as referenced in the MMSA-2024-00337, MMSA-2025-00493, MMSA-2025-00540 advisory. - Mattermost versions 11 fail to properly restrict access to archived channel search API which allows guest users ...

Incorrect Default Permissions

Overview Affected versions of this package are vulnerable to Incorrect Default Permissions via the Agents plugin process. An attacker can access information about when users have read channels by querying channel member objects. Remediation Upgrade...

PT-2025-47329

Name of the Vulnerable Software and Affected Versions Mattermost versions 10.5.x through 10.5.11 Mattermost versions 10.11.x through 10.11.3 Description The Mattermost application does not properly enforce access permissions within the Agents plugin. This allows other users to determine when user...

5 Reasons Why Attackers Are Phishing Over LinkedIn

Phishing attacks are no longer confined to the email inbox, with 1 in 3 phishing attacks now taking place over non-email channels like social media, search engines, and messaging apps. LinkedIn in particular has become a hotbed for phishing attacks, and for good reason. Attackers are running...

CVE-2025-11776

Mattermost versions 11 fail to properly restrict access to archived channel search API which allows guest users to discover archived public channels via the /api/v4/teams/teamid/channels/searcharchived endpoint...

CVE-2025-41436

Mattermost versions 11.0 fail to properly enforce the "Allow users to view archived channels" setting which allows regular users to access archived channel content and files via the "Open in Channel" functionality from followed threads...

Incorrect Authorization

Overview Affected versions of this package are vulnerable to Incorrect Authorization via the /api/v4/teams/teamid/channels/searcharchived endpoint. An attacker can access information about archived public channels by sending crafted requests as a guest user. Remediation Upgrade...

Incorrect Authorization

Overview Affected versions of this package are vulnerable to Incorrect Authorization via the /api/v4/teams/teamid/channels/searcharchived endpoint. An attacker can access information about archived public channels by sending crafted requests as a guest user. Remediation Upgrade...

Incorrect Authorization

Overview Affected versions of this package are vulnerable to Incorrect Authorization via the /api/v4/teams/teamid/channels/searcharchived endpoint. An attacker can access information about archived public channels by sending crafted requests as a guest user. Remediation Upgrade...

Incorrect Authorization

Overview Affected versions of this package are vulnerable to Incorrect Authorization via the /api/v4/teams/teamid/channels/searcharchived endpoint. An attacker can access information about archived public channels by sending crafted requests as a guest user. Remediation Upgrade...

Incorrect Authorization

Overview github.com/mattermost/mattermost/server/channels/app is a private-cloud Slack alternative Affected versions of this package are vulnerable to Incorrect Authorization via the /api/v4/teams/teamid/channels/searcharchived endpoint. An attacker can access information about archived public...

GHSA-X3HX-CH7P-8XGG Mattermost allows regular users to access archived channel content and files

Mattermost versions 11.0 fail to properly enforce the "Allow users to view archived channels" setting which allows regular users to access archived channel content and files via the "Open in Channel" functionality from followed threads...

Mattermost allows regular users to access archived channel content and files

Mattermost versions 11.0 fail to properly enforce the "Allow users to view archived channels" setting which allows regular users to access archived channel content and files via the "Open in Channel" functionality from followed threads...

Mattermost fails to properly restrict access to archived channel search API

Mattermost versions 11 fail to properly restrict access to archived channel search API which allows guest users to discover archived public channels via the /api/v4/teams/teamid/channels/searcharchived endpoint...

Incorrect Authorization

Overview Affected versions of this package are vulnerable to Incorrect Authorization via the /api/v4/teams/teamid/channels/searcharchived endpoint. An attacker can access information about archived public channels by sending crafted requests as a guest user. Remediation Upgrade...

Incorrect Authorization

Overview Affected versions of this package are vulnerable to Incorrect Authorization via the /api/v4/teams/teamid/channels/searcharchived endpoint. An attacker can access information about archived public channels by sending crafted requests as a guest user. Remediation Upgrade...

Incorrect Authorization

Overview Affected versions of this package are vulnerable to Incorrect Authorization via the /api/v4/teams/teamid/channels/searcharchived endpoint. An attacker can access information about archived public channels by sending crafted requests as a guest user. Remediation Upgrade...

Incorrect Authorization

Overview Affected versions of this package are vulnerable to Incorrect Authorization via the /api/v4/teams/teamid/channels/searcharchived endpoint. An attacker can access information about archived public channels by sending crafted requests as a guest user. Remediation Upgrade...

Incorrect Authorization

Overview Affected versions of this package are vulnerable to Incorrect Authorization due to improper enforcement of the Allow users to view archived channels setting in the threads interface. An attacker can gain unauthorized access to archived channel content and files by using the "Open in...

Incorrect Authorization

Overview Affected versions of this package are vulnerable to Incorrect Authorization due to improper enforcement of the Allow users to view archived channels setting in the threads interface. An attacker can gain unauthorized access to archived channel content and files by using the "Open in...