Mattermost doesn't escape some variables that could contain malicious content during error page composition

Mattermost versions 11.5.x = 11.5.1, 10.11.x = 10.11.13 fail to escape some variables that could contain malicious content during error page composition which allows an attacker with access to edit some site configuration to execute some malicious code via injecting some JS as part of those...

PT-2026-32956

Name of the Vulnerable Software and Affected Versions Jellyfin versions prior to 10.11.7 Description A flaw exists in the subtitle upload endpoint '/Videos/itemId/Subtitles' where the Format field is not validated. This allows path traversal via the file extension, enabling arbitrary file write...

Mattermost 安全漏洞

Mattermost is an open-source collaboration platform developed by the American company Mattermost. Vulnerabilities exist in Mattermost versions 11.2.2 and earlier of the 11.2.x series, as well as versions 10.11.10 and earlier of the 10.11.x series, 11.4.0 and earlier of the 11.4.x series, and 11.3...

Mattermost 安全漏洞

Mattermost is an open-source collaboration platform developed by the American company Mattermost. There is a security vulnerability in Mattermost, which stems from the lack of verification of the size of extracted files during decompression. This vulnerability could allow authenticated users to b...

EUVD-2026-12518

Mattermost versions 10.11.x = 10.11.10 fail to properly validate permission requirements in the team member roles API endpoint which allows team administrators to demote members to guest role. Mattermost Advisory ID: MMSA-2025-00531...

EUVD-2026-12516

Mattermost versions 10.11.x = 10.11.10 Fail to invalidate cached permalink preview data when a user loses channel access which allows the user to continue viewing private channel content via previously cached permalink previews until cache reset or relogin.. Mattermost Advisory ID: MMSA-2026-0058...

CVE-2026-1629

Mattermost versions 10.11.x = 10.11.10 Fail to invalidate cached permalink preview data when a user loses channel access which allows the user to continue viewing private channel content via previously cached permalink previews until cache reset or relogin.. Mattermost Advisory ID: MMSA-2026-0058...

CVE-2026-2454 DoS in Calls plugin via malformed msgpack in websocket request.

Mattermost versions 11.3.x = 11.3.0, 11.2.x = 11.2.2, 10.11.x = 10.11.10 fail to handle incorrectly reported array lengths which allows malicious user to cause OOM errors and crash the server via sending corrupted msgpack frames within websocket messages to calls plugin. Mattermost Advisory ID:...

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-2025-14573

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...

Mattermost 安全漏洞

Mattermost is an open-source collaboration platform developed by the American company Mattermost. Versions of Mattermost such as 11.1.2 and earlier 11.1.x series, 10.11.9 and earlier 10.11.x series, and 11.2.1 and earlier 11.2.x series have security vulnerabilities. These vulnerabilities stem fro...

CVE-2026-20796

Mattermost versions 10.11.x = 10.11.9 fail to properly validate channel membership at the time of data retrieval which allows a deactivated user to learn team names they should not have access to via a race condition in the /commonteams API endpoint.. Mattermost Advisory ID: MMSA-2025-00549...

PT-2026-7984

Name of the Vulnerable Software and Affected Versions Mattermost versions 10.11.0 through 10.11.9 Description Mattermost versions 10.11.0 through 10.11.9 do not properly validate channel membership when retrieving data, potentially allowing a deactivated user to learn team names they should not...

CVE-2025-14822 DoS from quadratic complexity in model.ParseHashtags

Mattermost versions 10.11.x = 10.11.8 fail to validate input size before processing hashtags which allows an authenticated attacker to exhaust CPU resources via a single HTTP request containing a post with thousands space-separated tokens...

CVE-2025-14822

Mattermost contains a vulnerability (CVE-2025-14822) affecting versions 10.11.x up to 10.11.8 where input size is not validated before processing hashtags. An authenticated attacker can exhaust CPU resources with a single HTTP POST containing thousands of space-separated tokens in a post, leading...

Mattermost 安全漏洞

Mattermost is an open source collaboration platform from Mattermost, Inc. in the United States. A security vulnerability exists in Mattermost versions 10.11.4 and prior to 10.11.x and 10.5.12 and prior to 10.5.x. The vulnerability stems from unvalidated user permissions and could lead to...

CVE-2025-55074 Channel member objects leak read status

Mattermost versions 10.11.x = 10.11.3, 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...

GHSA-XR3W-RMVJ-F6M7 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-2025-41443

Mattermost versions 10.5.x = 10.5.12, 10.11.x = 10.11.2 fail to properly validate guest user permissions when accessing channel information which allows guest users to discover active public channels and their metadata via the /api/v4/teams/teamid/channels/ids endpoint...

CVE-2025-41443 Guest user can discover active public channels

Mattermost versions 10.5.x = 10.5.12, 10.11.x = 10.11.2 fail to properly validate guest user permissions when accessing channel information which allows guest users to discover active public channels and their metadata via the /api/v4/teams/teamid/channels/ids endpoint...