CVE-2025-55073
Medium · 5.4Mattermost allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL
CVSS
5.4
EPSS
0.2%
Published
Nov 14, 2025
CISA due date
—
The record
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.
Affected packages
| Ecosystem | Package | Introduced | Fixed |
|---|---|---|---|
| Go | github.com/mattermost/mattermost-server | 10.11.0 | 10.11.4 |
| Go | github.com/mattermost/mattermost-server | 10.12.0 | 10.12.1 |
| Go | github.com/mattermost/mattermost-server | 10.5.0 | 10.5.12 |
| Go | github.com/mattermost/mattermost-server | 10.5.0+incompatible | 10.5.12+incompatible |
| Go | github.com/mattermost/mattermost-server/v5 | 0 | No fix |
| Go | github.com/mattermost/mattermost-server/v6 | 0 | No fix |
| Go | github.com/mattermost/mattermost/server/v8 | 0 | 8.0.0-20250929212932-a41db04d2746 |
| go | github.com/mattermost/mattermost-server | 10.11.0 | 10.11.4 |
| go | github.com/mattermost/mattermost-server | 10.12.0 | 10.12.1 |
| go | github.com/mattermost/mattermost-server | 10.5.0 | 10.5.12 |
Related vulnerabilities
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