Vulnerability · Published Nov 14, 2025 · Assigned by Mattermost
CVE-2025-55073MS Teams plugin OAuth allows editing arbitrary posts
Medium 5.4
In plain English
A medium-severity missing authentication in Mattermost from Mattermost. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 9% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)5.4Medium
Exploit odds (30 days)0.2%top 90.7% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/mattermost/mattermost-server | 10.11.4+incompatible, 10.12.1+incompatible, 10.5.12+incompatible | GO-2025-4129 |
| Go | github.com/mattermost/mattermost-server | 10.5.12 | GHSA-ff85-qw3h-g9vp |
| Go | github.com/mattermost/mattermost-server | 10.12.1 | GHSA-ff85-qw3h-g9vp |
| Go | github.com/mattermost/mattermost-server | 10.11.4 | GHSA-ff85-qw3h-g9vp |
| Go | github.com/mattermost/mattermost-server/v5 | no fix listed | GO-2025-4129 |
| Go | github.com/mattermost/mattermost-server/v6 | no fix listed | GO-2025-4129 |
| Go | github.com/mattermost/mattermost/server/v8 | 8.0.0-20250929212932-a41db04d2746 | GHSA-ff85-qw3h-g9vp |
| Go | github.com/mattermost/mattermost/server/v8 | 8.0.0-20250929212932-a41db04d2746 | GO-2025-4129 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Mattermost | Mattermost | 10.11.0 – through 10.11.310.5.0 – through 10.5.1110.12.0 – through 10.12.0 |
Weakness: CWE-306 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L