CVE-2025-55073
Medium
Description
Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11, 10.12.x <= 10.12.0 fail to validate the relationship between the post being updated and the MSTeams plugin OAuth flow which allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL.
SeverityMedium
CVSS5.4
Exploit probability—
Product
Mattermost Server
PublishedNov 14, 2025
First seenNov 14, 2025
Weakness typeCWE-306Missing authentication for critical function
How to fix
Update
- mattermost mattermost_server10.5.12, 10.11.4, 10.12.1 or later
- github.com/mattermost/mattermost-server10.11.4, 10.5.12, 10.12.1, 10.5.12+incompatible, 10.11.4+incompatible, 10.12.1+incompatible or later
- github.com/mattermost/mattermost/server/v88.0.0-20250929212932-a41db04d2746 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mattermost mattermost_server | 10.5.0 ≤ v < 10.5.12, 10.11.0 ≤ v < 10.11.4, 10.12.0 ≤ v < 10.12.1 | 10.5.12, 10.11.4, 10.12.1 |
| github.com/mattermost/mattermost-serverGo | 10.11.0 ≤ v < 10.11.4, 10.5.0 ≤ v < 10.5.12, 10.12.0 ≤ v < 10.12.1, 10.5.0+incompatible ≤ v < 10.5.12+incompatible, 10.11.0+incompatible ≤ v < 10.11.4+incompatible, 10.12.0+incompatible ≤ v < 10.12.1+incompatible | 10.11.4, 10.5.12, 10.12.1, 10.5.12+incompatible, 10.11.4+incompatible, 10.12.1+incompatible |
| github.com/mattermost/mattermost/server/v8Go | v < 8.0.0-20250929212932-a41db04d2746 | 8.0.0-20250929212932-a41db04d2746 |
| github.com/mattermost/mattermost-server/v5Go | No range specified | — |
| github.com/mattermost/mattermost-server/v6Go | No range specified | — |
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