CVE-2025-6227: mattermost server Credential Exposure

Description

Mattermost versions 10.5.x <= 10.5.7, 9.11.x <= 9.11.16 fail to negotiate a new token when accepting the invite which allows a user that intercepts both invite and password to send synchronization payloads to the server that originally created the invite via the REST API.

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CVSS v3.1 Score

2.2

LOW

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

Weakness Type (CWE)

CWE-522 CWE-522

Affected Products

Vendor	Product	Versions
mattermost	mattermost_server	9.11.0 — 9.11.17
mattermost	mattermost_server	10.5.0 — 10.5.8

References

Advisories & Patches

https://mattermost.com/security-updates

Frequently Asked Questions

What is CVE-2025-6227? +

Mattermost versions 10.5.x <= 10.5.7, 9.11.x <= 9.11.16 fail to negotiate a new token when accepting the invite which allows a user that intercepts both invite and password to send synchronization payloads to the server that originally created the invite via the REST API. It has a CVSS v3.1 base score of 2.2 (LOW).

How severe is CVE-2025-6227? +

CVE-2025-6227 has a CVSS v3.1 score of 2.2 out of 10, rated LOW. This is a low-severity vulnerability with limited impact.

What products are affected by CVE-2025-6227? +

CVE-2025-6227 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-2025-6227? +

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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