Github.Com Mattermost Mattermost Server V8 vulnerabilities

CVE-2023-50333 [LOW] CWE-284 Mattermost allows demoted guests to change group names Mattermost allows demoted guests to change group names Mattermost fails to update the permissions of the current session for a user who was just demoted to guest, allowing freshly demoted guests to change group names.

CVE-2025-13324 [MEDIUM] CWE-863 Mattermost has an Invite Token Replay Vulnerability via Channel Membership Manipulation Mattermost has an Invite Token Replay Vulnerability via Channel Membership Manipulation Mattermost versions 10.11.x < 10.11.5, 11.0.x < 11.0.4, 10.12.x < 10.12.2 fail to invalidate remote cluster invite tokens when using the legacy (version 1) protocol or when the confirming party does not provide a refreshed token, which allows an attacker who has obtained an invite token to

CVE-2026-22545 [LOW] CWE-863 Mattermost fails to validate user's authentication method when processing account auth type switch Mattermost fails to validate user's authentication method when processing account auth type switch Mattermost versions 10.11.x <= 10.11.10 fail to validate user's authentication method when processing account auth type switch which allows an authenticated attacker to change account password without confirmation via falsely claiming a different auth provider.. Mattermos

CVE-2026-6334 [LOW] CWE-305 Mattermost doesn't enforce client identity binding during the OAuth authorization code redemption flow Mattermost doesn't enforce client identity binding during the OAuth authorization code redemption flow Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to enforce client identity binding during the OAuth authorization code redemption flow which allows an authenticated OAuth client to redeem authorization codes issued to a different client via a crafted

CVE-2025-54499 [LOW] CWE-208 Mattermost has an Observable Timing Discrepancy vulnerability Mattermost has an Observable Timing Discrepancy vulnerability Mattermost versions 10.5.x <= 10.5.10, 10.11.x <= 10.11.2 fail to use constant-time comparison for sensitive string comparisons which allows attackers to exploit timing oracles to perform byte-by-byte brute force attacks via response time analysis on Cloud API keys and OAuth client secrets.

CVE-2025-13352 [LOW] CWE-1287 Mattermost GitHub Plugin Bot Identity Validation Bypass Allows Arbitrary GitHub Reaction Injection Mattermost GitHub Plugin Bot Identity Validation Bypass Allows Arbitrary GitHub Reaction Injection Mattermost versions 10.11.x <= 10.11.6 and Mattermost GitHub plugin versions <=2.4.0 fail to validate plugin bot identity in reaction forwarding which allows attackers to hijack the GitHub reaction feature to make users add reactions to arbitrary GitHub objects via craft

CVE-2024-29221 [MEDIUM] CWE-284 Mattermost Server Improper Access Control Mattermost Server Improper Access Control Improper Access Control in Mattermost Server versions 9.5.x before 9.5.2, 9.4.x before 9.4.4, 9.3.x before 9.3.3, 8.1.x before 8.1.11 lacked proper access control in the `/api/v4/users/me/teams` endpoint allowing a team admin to get the invite ID of their team, thus allowing them to invite users, even if the "Add Members" permission was explicitly removed from team admins.

CVE-2025-3913 [MEDIUM] CWE-863 Mattermost improperly allows team administrators to modify team invites Mattermost improperly allows team administrators to modify team invites Mattermost versions 10.7.x <= 10.7.0, 10.6.x <= 10.6.2, 10.5.x <= 10.5.3, 9.11.x <= 9.11.12 fail to properly validate permissions when changing team privacy settings, allowing team administrators without the 'invite user' permission to access and modify team invite IDs via the /api/v4/teams/:teamId/privacy endpoint.

CVE-2024-32939 [MEDIUM] CWE-284 Mattermost doesn't redact remote users' original email addresses Mattermost doesn't redact remote users' original email addresses Mattermost versions 9.9.x <= 9.9.1, 9.5.x <= 9.5.7, 9.10.x <= 9.10.0, 9.8.x <= 9.8.2, when shared channels are enabled, fail to redact remote users' original email addresses stored in user props when email addresses are otherwise configured not to be visible in the local server.

CVE-2025-22449 [LOW] CWE-863 Mattermost Incorrect Authorization vulnerability Mattermost Incorrect Authorization vulnerability Mattermost versions 9.11.x <= 9.11.5 fail to enforce invite permissions, which allows team admins, with no permission to invite users to their team, to invite users by updating the "allow_open_invite" field via making their team public.

CVE-2025-53971 [LOW] CWE-863 Mattermost Fails to Properly Validate Team Role Modification Mattermost Fails to Properly Validate Team Role Modification Mattermost versions 10.5.x <= 10.5.8, 9.11.x <= 9.11.17 fail to properly validate authorization for team scheme role modifications which allows Team Admins to demote Team Members to Guests via the PUT /api/v4/teams/team-id/members/user-id/schemeRoles API endpoint.

CVE-2025-47700 [LOW] CWE-918 Mattermost Server SSRF Vulnerability via the Agents Plugin Mattermost Server SSRF Vulnerability via the Agents Plugin Mattermost Server versions 10.5.x <= 10.5.9 utilizing the Agents plugin fail to reject empty request bodies which allows users to trick users into clicking malicious links via post actions

CVE-2025-6227 [LOW] CWE-522 Mattermost has Insufficiently Protected Credentials Mattermost has Insufficiently Protected Credentials Mattermost versions 10.5.x <= 10.5.7, 9.11.x <= 9.11.16 fail to negotiate a new token when accepting the invite which allows a user that intercepts both invite and password to send synchronization payloads to the server that originally created the invite via the REST API.

CVE-2025-55074 [LOW] CWE-276 Mattermost allows other users to determine when users had read channels via channel member objects Mattermost allows other users to determine when users had read channels via channel member objects Mattermost versions 10.11.x <= 10.11.3, and 10.5.x <= 10.5.11 fail to enforce access permissions on the Agents plugin which allows other users to determine when users had read channels via channel member objects.

CVE-2024-10214 [LOW] CWE-303 Mattermost incorrectly issues two sessions when using desktop SSO Mattermost incorrectly issues two sessions when using desktop SSO Mattermost versions 9.11.X <= 9.11.1, 9.5.x <= 9.5.9 incorrectly issues two sessions when using desktop SSO - one in the browser and one in desktop with incorrect settings.

CVE-2024-21848 [LOW] CWE-273 Mattermost Server Improper Access Control Mattermost Server Improper Access Control Improper Access Control in Mattermost Server versions 8.1.x before 8.1.11 allows an attacker that is in a channel with an active call to keep participating in the call even if they are removed from the channel

CVE-2025-24866 [LOW] CWE-863 Mattermost Fails to Enforce Proper Access Controls on `/api/v4/audits` Endpoint Mattermost Fails to Enforce Proper Access Controls on `/api/v4/audits` Endpoint Mattermost versions 9.11.x <= 9.11.8 fail to enforce proper access controls on the /api/v4/audits endpoint, allowing users with delegated granular administration roles who lack access to Compliance Monitoring to retrieve User Activity Logs.

CVE-2025-1792 [LOW] CWE-863 Mattermost fails to properly enforce access controls for guest users Mattermost fails to properly enforce access controls for guest users Mattermost versions 10.7.x <= 10.7.0, 10.5.x <= 10.5.3, 9.11.x <= 9.11.12 fail to properly enforce access controls for guest users accessing channel member information, allowing authenticated guest users to view metadata about members of public channels via the channel members API endpoint.

CVE-2025-14573 [LOW] CWE-862 Mattermost fails to enforce invite permissions when updating team settings Mattermost fails to enforce invite permissions when updating team settings Mattermost versions 10.11.x <= 10.11.9 fail to enforce invite permissions when updating team settings, which allows team administrators without proper permissions to bypass restrictions and add users to their team via API requests. Mattermost Advisory ID: MMSA-2025-00561

CVE-2025-2570 [LOW] CWE-863 Mattermost Fails to Check User Access to `ExperimentalSettings` Mattermost Fails to Check User Access to `ExperimentalSettings` Mattermost versions 10.5.x <= 10.5.2, 9.11.x <= 9.11.11 fail to check `RestrictSystemAdmin` setting if user doesn't have access to `ExperimentalSettings` which allows a System Manager to access `ExperimentSettings` when `RestrictSystemAdmin` is true via System Console.