CVE-2025-8402
Medium
Description
Mattermost versions 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 9.11.x <= 9.11.17, 10.10.x <= 10.10.0, 10.9.x <= 10.9.3 fail to validate import data which allows a system admin to crash the server via the bulk import feature.
SeverityMedium
CVSS4.9
Exploit probability—
Product
Mattermost Server
PublishedAug 21, 2025
First seenAug 21, 2025
Weakness typeCWE-1287CWE-1287CWE-476NULL pointer dereference
How to fix
Update
- mattermost mattermost_server9.11.18, 10.5.9, 10.8.4, 10.9.4 or later
- github.com/mattermost/mattermost-server10.8.4, 10.5.9, 10.9.4, 10.10.1, 9.11.18, 9.11.18+incompatible, 10.5.9+incompatible, 10.8.4+incompatible, 10.9.4+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 < 10.9.4, 10.10.0 | 9.11.18, 10.5.9, 10.8.4, 10.9.4 |
| github.com/mattermost/mattermost-serverGo | 10.8.0 ≤ v < 10.8.4, 10.5.0 ≤ v < 10.5.9, 10.9.0 ≤ v < 10.9.4, 10.10.0 ≤ v < 10.10.1, 9.11.0 ≤ v < 9.11.18, 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 < 10.9.4+incompatible, 10.10.0+incompatible ≤ v < 10.10.1+incompatible | 10.8.4, 10.5.9, 10.9.4, 10.10.1, 9.11.18, 9.11.18+incompatible, 10.5.9+incompatible, 10.8.4+incompatible, 10.9.4+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 ≤ 6.7.2, No range specified | — |
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