What is CVE-2025-4128?

CVE-2025-4128 is a low-severity vulnerability in Mattermost, classified under Incorrect Authorization. CVSS score: 3.1/10. Published 2025-06-11.

How severe is CVE-2025-4128?

Low severity. CVSS v3 base score is 3.1 out of 10.

Auth bypass in Mattermost

CVE-2025-4128

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 c…

Vulnerability class: Broken Access Control

EPSS: 0.002 (7.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 3.1 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N.

Affected products

Mattermost — versions 10.5.0, 9.11.0, 10.8.0
Mattermost Mattermost_server

Weakness classification (CWE)

CWE-863 — Incorrect Authorization

References

responsibledisclosure@mattermost.com (Vendor Advisory)

Frequently asked questions

What is CVE-2025-4128?: CVE-2025-4128 is a low-severity vulnerability in Mattermost, classified under Incorrect Authorization. CVSS score: 3.1/10. Published 2025-06-11.
How severe is CVE-2025-4128?: Low severity. CVSS v3 base score is 3.1 out of 10.