What is CVE-2025-49222?

CVE-2025-49222 is a medium-severity vulnerability in Mattermost, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 6.8/10. Published 2025-08-21.

How severe is CVE-2025-49222?

Medium severity. CVSS v3 base score is 6.8 out of 10.

Arbitrary file upload in Mattermost

CVE-2025-49222

Mattermost versions 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 9.11.x <= 9.11.17, 10.9.x <= 10.9.2, 10.10.x <= 10.10.0 fail to validate upload types in remote cluster upload sessions which allows a system admin to upload non-attachment file types via shared channels that could potentially be placed in arbitrary filesystem directories.

Vulnerability class: Unrestricted File Upload

EPSS: 0.003 (22.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.8 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N.

Affected products

Mattermost — versions 10.8.0, 10.5.0, 9.11.0
Mattermost Mattermost_server — versions 10.10.0

Weakness classification (CWE)

CWE-434 — Unrestricted Upload of File with Dangerous Type

References

responsibledisclosure@mattermost.com (Vendor Advisory)

Frequently asked questions

What is CVE-2025-49222?: CVE-2025-49222 is a medium-severity vulnerability in Mattermost, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 6.8/10. Published 2025-08-21.
How severe is CVE-2025-49222?: Medium severity. CVSS v3 base score is 6.8 out of 10.