CVE-2025-3227: mattermost server Auth Bypass — Fix

Description

Mattermost versions 10.5.x <= 10.5.5, 9.11.x <= 9.11.15, 10.8.x <= 10.8.0, 10.7.x <= 10.7.2, 10.6.x <= 10.6.5 fail to properly enforce channel member management permissions in playbook runs, allowing authenticated users without the 'Manage Channel Members' permission to add or remove users from public and private channels by manipulating playbook run participants when the run is linked to a channel.

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CVSS v3.1 Score

4.3

MEDIUM

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

Weakness Type (CWE)

CWE-863 Incorrect Authorization

Affected Products

Vendor	Product	Versions
mattermost	mattermost_server	9.11.0 — 9.11.16
mattermost	mattermost_server	10.5.0 — 10.5.6
mattermost	mattermost_server	10.6.0 — 10.6.6
mattermost	mattermost_server	10.7.0 — 10.7.3
mattermost	mattermost_server	All
mattermost	mattermost_server	All
mattermost	mattermost_server	All
mattermost	mattermost_server	All

References

Advisories & Patches

https://mattermost.com/security-updates

Frequently Asked Questions

What is CVE-2025-3227? +

Mattermost versions 10.5.x <= 10.5.5, 9.11.x <= 9.11.15, 10.8.x <= 10.8.0, 10.7.x <= 10.7.2, 10.6.x <= 10.6.5 fail to properly enforce channel member management permissions in playbook runs, allowing authenticated users without the 'Manage Channel Members' permission to add or remove users from public and private channels by manipulating playbook run participants when the run is linked to a channel. It has a CVSS v3.1 base score of 4.3 (MEDIUM).

How severe is CVE-2025-3227? +

CVE-2025-3227 has a CVSS v3.1 score of 4.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-3227? +

CVE-2025-3227 affects products from mattermost, specifically: mattermost_server. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-3227? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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