CVE-2025-49222

MEDIUM

Mattermost Server < 9.11.18 - Unrestricted File Upload

Title source: rule

Description

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.

References (1)

Core 1

Core References

Vendor Advisory

https://mattermost.com/security-updates

Scores

CVSS v3 6.8

EPSS 0.0005

EPSS Percentile 15.8%

Attack Vector NETWORK

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

CISA SSVC

Vulnrichment

Exploitation none

Automatable no

Technical Impact partial

Details

CWE

CWE-434

Status published

Products (5)

mattermost/mattermost 0 - 8.0.0-20250708173752-d6b35c41f0ae5Go

mattermost/mattermost-server 0 (2 CPE variants)Go

mattermost/mattermost-server 10.8.0 - 10.8.4Go

mattermost/mattermost_server 10.10.0

mattermost/mattermost_server 9.11.0 - 9.11.18

Published Aug 21, 2025

Tracked Since Feb 18, 2026