Vulnerability · Published Oct 16, 2025 · Assigned by Mattermost
CVE-2025-41443Guest user can discover active public channels
Medium 4.3
In plain English
A medium-severity missing authorization in Mattermost from Mattermost. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 24% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)4.3Medium
Exploit odds (30 days)0.3%top 75.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
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/{team_id}/channels/ids` endpoint
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/mattermost/mattermost-server | 10.5.11 | GHSA-7cr3-38jm-6p45 |
| Go | github.com/mattermost/mattermost-server | 10.11.3 | GHSA-7cr3-38jm-6p45 |
| Go | github.com/mattermost/mattermost-server | no fix listed | GO-2025-4031 |
| Go | github.com/mattermost/mattermost/server/v8 | 8.0.0-20250822090405-e8c7e7d0252b | GHSA-7cr3-38jm-6p45 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Mattermost | Mattermost | 10.5.0 – through 10.5.1210.11.0 – through 10.11.2 |
Weakness: CWE-862 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N