Vulnerability · Published Dec 17, 2025 · Assigned by Mattermost
CVE-2025-13352Mattermost GitHub Plugin allows unauthorized GitHub reactions via reaction forwarding hijacking
Low 3.0
In plain English
A low-severity security flaw 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 7% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)3.0Low
Exploit odds (30 days)0.2%top 93.0% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Mattermost versions 10.11.x <= 10.11.6 and Mattermost GitHub plugin versions <=2.4.0 fail to validate plugin bot identity in reaction forwarding which allows attackers to hijack the GitHub reaction feature to make users add reactions to arbitrary GitHub objects via crafted notification posts.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/mattermost/mattermost | 10.11.7-0.20251106103514-3b05384dd014 | GHSA-jf5h-xfw4-p8gp |
| Go | github.com/mattermost/mattermost | 11.1.0 | GHSA-jf5h-xfw4-p8gp |
| Go | github.com/mattermost/mattermost | 11.1.0+incompatible | GO-2025-4247 |
| Go | github.com/mattermost/mattermost-plugin-github | 1.0.1-0.20250829075715-0deffcfc6bee | GHSA-jf5h-xfw4-p8gp |
| Go | github.com/mattermost/mattermost-plugin-github | 1.0.1-0.20250829075715-0deffcfc6bee | GO-2025-4247 |
| Go | github.com/mattermost/mattermost-server | no fix listed | GO-2025-4247 |
| Go | github.com/mattermost/mattermost-server/v5 | no fix listed | GO-2025-4247 |
| Go | github.com/mattermost/mattermost-server/v6 | no fix listed | GO-2025-4247 |
| Go | github.com/mattermost/mattermost/server/v8 | no fix listed | GO-2025-4247 |
| Go | github.com/mattermost/mattermost/server/v8 | 10.11.7-0.20251106103514-3b05384dd014 | GHSA-jf5h-xfw4-p8gp |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Mattermost | Mattermost | 10.11.0 – through 10.11.6 |
Weakness: CWE-1287 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:N/I:L/A:N