CVE-2025-49222
Medium
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.
SeverityMedium
CVSS6.8
Exploit probability—
Product
Mattermost Server
PublishedAug 21, 2025
First seenAug 21, 2025
Weakness typeCWE-434Unrestricted upload of dangerous file type
How to fix
Update
- mattermost mattermost_server9.11.18, 10.5.9, 10.8.4, 10.9.3 or later
- github.com/mattermost/mattermost-server10.8.4, 10.5.9, 9.11.18, 10.9.3, 10.10.1, 9.11.18+incompatible, 10.5.9+incompatible, 10.8.4+incompatible, 10.9.3+incompatible, 10.10.1+incompatible or later
- github.com/mattermost/mattermost/server/v88.0.0-20250708173752-d6b35c41f0ae5 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mattermost mattermost_server | 9.11.0 ≤ v < 9.11.18, 10.5.0 ≤ v < 10.5.9, 10.8.0 ≤ v < 10.8.4, 10.9.0 ≤ v < 10.9.3, 10.10.0 | 9.11.18, 10.5.9, 10.8.4, 10.9.3 |
| github.com/mattermost/mattermost-serverGo | 10.8.0 ≤ v < 10.8.4, 10.5.0 ≤ v < 10.5.9, 9.11.0 ≤ v < 9.11.18, 10.9.0 ≤ v < 10.9.3, 10.10.0 ≤ v < 10.10.1, 9.11.0+incompatible ≤ v < 9.11.18+incompatible, 10.5.0+incompatible ≤ v < 10.5.9+incompatible, 10.8.0+incompatible ≤ v < 10.8.4+incompatible, 10.9.0+incompatible ≤ v < 10.9.3+incompatible, 10.10.0+incompatible ≤ v < 10.10.1+incompatible | 10.8.4, 10.5.9, 9.11.18, 10.9.3, 10.10.1, 9.11.18+incompatible, 10.5.9+incompatible, 10.8.4+incompatible, 10.9.3+incompatible, 10.10.1+incompatible |
| github.com/mattermost/mattermost/server/v8Go | v < 8.0.0-20250708173752-d6b35c41f0ae5, No range specified | 8.0.0-20250708173752-d6b35c41f0ae5 |
| github.com/mattermost/mattermost-server/v5Go | v ≤ 5.39.3, No range specified | — |
| github.com/mattermost/mattermost-server/v6Go | v ≤ 5.7.2, No range specified | — |
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