CVE-2025-14350 Information disclosure via channel mentions in posts
Authenticated users can discover private team names and URLs by observing API responses to channel mentions, exposing sensitive organizational structure.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-14350?
CVE-2025-14350 is a medium-severity vulnerability in Mattermost Mattermost Server, published on 16 Feb 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Mattermost versions 11.1.x <= 11.1.2, 10.11.x <= 10.11.9, 11.2.x <= 11.2.1 fail to properly validate team membership when processing channel mentions which allows authenticated users to determine the existence of teams and their URL names via posting channel shortlinks and observing the channel_mentions property in the API response. Mattermost Advisory ID: MMSA-2025-00563
Weakness: CWE-862
Which versions are affected by CVE-2025-14350?
17 open source packages ship an affected version, including github.com/mattermost/mattermost-server, github.com/mattermost/mattermost-server/v5 and github.com/mattermost/mattermost-server/v6. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/mattermost/mattermost-server Go | All versions | None |
github.com/mattermost/mattermost-server Go | All versions | 5.3.2-0.20251209134645-761e56bb11cc |
github.com/mattermost/mattermost-server Go | All versions | 5.3.2-0.20251209134645-761e56bb11cc |
github.com/mattermost/mattermost-server Go | From 10.11.0 | None |
github.com/mattermost/mattermost-server Go | From 10.11.0 | None |
github.com/mattermost/mattermost-server Go | From 10.11.0+incompatible | None |
11 more packages
github.com/mattermost/mattermost-server Go | From 11.1.0 | None |
github.com/mattermost/mattermost-server Go | From 11.1.0 | None |
github.com/mattermost/mattermost-server Go | From 11.1.0+incompatible | None |
github.com/mattermost/mattermost-server Go | From 11.2.0 | None |
github.com/mattermost/mattermost-server Go | From 11.2.0 | None |
github.com/mattermost/mattermost-server Go | From 11.2.0+incompatible | None |
github.com/mattermost/mattermost-server/v5 Go | All versions | None |
github.com/mattermost/mattermost-server/v6 Go | All versions | None |
github.com/mattermost/mattermost/server/v8 Go | All versions | 8.0.0-20251209134645-761e56bb11cc |
github.com/mattermost/mattermost/server/v8 Go | All versions | 8.0.0-20251209134645-761e56bb11cc |
github.com/mattermost/mattermost/server/v8 Go | All versions | 8.0.0-20251209134645-761e56bb11cc |
Products include Mattermost Mattermost Server.
How do I fix CVE-2025-14350?
Upgrade github.com/mattermost/mattermost-server to 5.3.2-0.20251209134645-761e56bb11cc or later.
Is CVE-2025-14350 being exploited?
There is no known exploitation of CVE-2025-14350 in the wild and no public exploit code.
Other vulnerabilities in Mattermost Mattermost Server
- CVE-2025-12419 Account takeover on OAuth/OpenID-enabled servers
- CVE-2025-12421 Account Takeover via Code Exchange Endpoint
- CVE-2025-4981 Path Traversal Leading to RCE by Any Authenticated Mattermost User
- CVE-2025-20051 Arbitrary file read via block duplication in Mattermost Boards
- CVE-2025-25279 Arbitrary file read in Mattermost Boards via import & export board archive
Sources
Also known as GHSA-57cc-2pf4-mhmx, GO-2026-4521.