SUSE CVE-2026-2578

Mattermost versions 11.3.x = 11.3.0 fail to preserve the redacted state of burn-on-read posts during deletion which allows channel members to access unrevealed burn-on-read message contents via the WebSocket post deletion event.. Mattermost Advisory ID: MMSA-2026-00579...

SUSE CVE-2026-4265

Mattermost versions 11.3.x = 11.3.0, 11.2.x = 11.2.2, 10.11.x = 10.11.10 fail to validate team-specific uploadfile permissions which allows a guest user to post files in channels where they lack uploadfile permission via uploading files in a team where they have permission and reusing the file...

SUSE CVE-2026-21386

Mattermost versions 11.3.x = 11.3.0, 11.2.x = 11.2.2, 10.11.x = 10.11.10 fail to use consistent error responses when handling the /mute command which allows an authenticated team member to enumerate private channels they are not authorized to know about via differing error messages for nonexisten...

SUSE CVE-2026-22545

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.. Mattermost Advisory ID:...

SUSE CVE-2026-24458

Mattermost versions 11.3.x = 11.3.0, 11.2.x = 11.2.2, 10.11.x = 10.11.10 fail to properly handle very long passwords, which allows an attacker to overload the server CPU and memory via executing login attempts with multi-megabyte passwords. Mattermost Advisory ID: MMSA-2026-00587...

SUSE CVE-2026-24692

Mattermost versions 11.3.x = 11.3.0, 11.2.x = 11.2.2, 10.11.x = 10.11.10 fail to properly enforce read permissions in search API endpoints which allows guest users without read permissions to access posts and files in channels via search API requests. Mattermost Advisory ID: MMSA-2025-00554...

SUSE CVE-2026-25780

Mattermost versions 11.3.x = 11.3.0, 11.2.x = 11.2.2, 10.11.x = 10.11.10 fail to bound memory allocation when processing DOC files which allows an authenticated attacker to cause server memory exhaustion and denial of service via uploading a specially crafted DOC file.. Mattermost Advisory ID:...

SUSE CVE-2026-25783

Mattermost versions 11.3.x = 11.3.0, 11.2.x = 11.2.2, 10.11.x = 10.11.10 fail to properly validate User-Agent header tokens which allows an authenticated attacker to cause a request panic via a specially crafted User-Agent header. Mattermost Advisory ID: MMSA-2026-00586...

SUSE CVE-2026-26246

Mattermost versions 11.3.x = 11.3.0, 11.2.x = 11.2.2, 10.11.x = 10.11.10 fail to bound memory allocation when processing PSD image files which allows an authenticated attacker to cause server memory exhaustion and denial of service via uploading a specially crafted PSD file. Mattermost Advisory I...

SUSE CVE-2026-26304

Mattermost versions 11.3.x = 11.3.0, 11.2.x = 11.2.2 fail to verify runcreate permission for empty playbookId, which allows team members to create unauthorized runs via the playbook run API. Mattermost Advisory ID: MMSA-2025-00542...

CVE-2026-3109

Mattermost Plugins versions =11.4 10.11.11.0 fail to validate webhook request timestamps which allows an attacker to corrupt Zoom meeting state in Mattermost via replayed webhook requests. Mattermost Advisory ID: MMSA-2026-00584...

Incorrect Authorization

Overview @openclaw/mattermost is an OpenClaw Mattermost channel plugin Affected versions of this package are vulnerable to Incorrect Authorization in the auth process. An attacker can gain unauthorized access by sending requests with add-on principals that are not bound to the intended deployment...

OpenClaw: Mattermost callback dispatch allowed non-allowlisted sender actions

Summary Mattermost interactive callback dispatch could run action handlers before normal sender authorization checks completed. Affected Packages / Versions - Package: openclaw npm - Affected: = 2026.3.22 - Latest released tag checked: v2026.3.23-2 630f1479c44f78484dfa21bb407cbe6f171dac87 - Lates...

Incorrect Authorization

Overview @openclaw/mattermost is an OpenClaw Mattermost channel plugin Affected versions of this package are vulnerable to Incorrect Authorization via the callback process. An attacker can execute unauthorized actions by sending specially crafted requests before sender authorization checks are...

GHSA-8883-9W57-VWV6 OpenClaw: Mattermost callback dispatch allowed non-allowlisted sender actions

Summary Mattermost interactive callback dispatch could run action handlers before normal sender authorization checks completed. Affected Packages / Versions - Package: openclaw npm - Affected: = 2026.3.22 - Latest released tag checked: v2026.3.23-2 630f1479c44f78484dfa21bb407cbe6f171dac87 - Lates...

GO-2026-4726 Mattermost fails to limit the size of responses from integration action endpoints in github.com/mattermost/mattermost-server

Mattermost fails to limit the size of responses from integration action endpoints 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...

GO-2026-4725 Mattermost fails to properly validate User-Agent header tokens in github.com/mattermost/mattermost-server

Mattermost fails to properly validate User-Agent header tokens 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 reports from...

CVE-2026-3115

A flaw was found in Mattermost. Authenticated guest users can exploit this vulnerability by retrieving group member IDs through the group retrieval endpoint. This failure to apply view restrictions allows them to enumerate user IDs that are outside their permitted visibility scope, leading to...

CVE-2026-3113

A flaw was found in Mattermost. The system fails to properly set file permissions on downloaded bulk exports. This vulnerability allows other local users on the server to read the sensitive contents of these bulk export files, leading to unauthorized information disclosure...

CVE-2026-3114

A flaw was found in Mattermost. Authenticated users with file upload permissions can exploit this vulnerability by uploading specially crafted zip archives, known as "zip bombs," which contain highly compressed entries. When these archives are decompressed, they exhaust server memory, leading to ...