CVE-2025-4128

Mattermost Guest User Information Disclosure Vulnerability

CVSS 3.1 LOWEPSS 0.2%CWE-863

Vexday Risk Score

8Low

SSVC decision (CISA)

Track

No exploitation signal → monitor

CVSS 3.1EPSS 0.2%KEV nãoPoC —Nuclei —Metasploit —Patch —

Lifecycle

11 Jun 2025Published on NVD

Recommendation: Monitor — no exploitation signal at the moment.

Mattermost versions 10.5.x <= 10.5.4, 9.11.x <= 9.11.13 fail to properly restrict API access to team information, allowing guest users to bypass permissions and view information about public teams they are not members of via a direct API call to /api/v4/teams/{team_id}.

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N

Affected products

Mattermost · Mattermost

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References

https://mattermost.com/security-updates