# CVE-2025-13352: Mattermost GitHub Plugin Bot Identity Validation Bypass Allows Arbitrary GitHub Reaction Injection

Source: https://junglewise.ai/threats/cve-2025-13352-mattermost-github-plugin-bot-identity-validation-bypass-allows  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-12-17  
License: CC BY 4.0 with a link back

CVE-2025-13352 · Severity: low · CVSS 3.1 · Published 2025-12-17

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.

Technologies: [github.com/mattermost/mattermost (Go)](https://junglewise.ai/threats/technologies/github-com-mattermost-mattermost), [github.com/mattermost/mattermost-plugin-github (Go)](https://junglewise.ai/threats/technologies/github-com-mattermost-mattermost-plugin-github), [github.com/mattermost/mattermost-server (Go)](https://junglewise.ai/threats/technologies/github-com-mattermost-mattermost-server), [github.com/mattermost/mattermost-server/v5 (Go)](https://junglewise.ai/threats/technologies/github-com-mattermost-mattermost-server-v5), [github.com/mattermost/mattermost-server/v6 (Go)](https://junglewise.ai/threats/technologies/github-com-mattermost-mattermost-server-v6), [github.com/mattermost/mattermost/server/v8 (Go)](https://junglewise.ai/threats/technologies/github-com-mattermost-mattermost-server-v8), [Mattermost Server](https://junglewise.ai/threats/technologies/server-public). Vendors: [Go](https://junglewise.ai/threats/vendors/go), [Mattermost](https://junglewise.ai/threats/vendors/mattermost).

## Quick answers

**Is CVE-2025-13352 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-13352 being exploited in the wild.

**How severe is CVE-2025-13352?** Low severity, with a CVSS score of 3.1, published 17 December 2025.

**Which products and versions are affected?** github.com/mattermost/mattermost (Go) SEMVER:introduced=0,fixed=10.11.7-0.20251106103514-3b05384dd014, SEMVER:introduced=11.0.0-alpha.1+incompatible,fixed=11.1.0+incompatible; github.com/mattermost/mattermost-plugin-github (Go) SEMVER:introduced=0,fixed=1.0.1-0.20250829075715-0deffcfc6bee; github.com/mattermost/mattermost-server (Go) SEMVER:introduced=10.11.0-rc1+incompatible; github.com/mattermost/mattermost-server/v5 (Go) SEMVER:introduced=0; and 2 more.

**Is there a fix for CVE-2025-13352?** Yes. github.com/mattermost/mattermost (Go): upgrade to 10.11.7-0.20251106103514-3b05384dd014, 11.1.0+incompatible or later; github.com/mattermost/mattermost-plugin-github (Go): upgrade to 1.0.1-0.20250829075715-0deffcfc6bee or later; github.com/mattermost/mattermost/server/v8 (Go): upgrade to 10.11.7-0.20251106103514-3b05384dd014 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2025-13352?** Check whether you run github.com/mattermost/mattermost (Go), github.com/mattermost/mattermost-plugin-github (Go), github.com/mattermost/mattermost-server (Go) or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- github.com/mattermost/mattermost (Go): upgrade to 10.11.7-0.20251106103514-3b05384dd014, 11.1.0+incompatible or later

  ```sh
  go get github.com/mattermost/mattermost@v11.1.0+incompatible
  ```

- github.com/mattermost/mattermost-plugin-github (Go): upgrade to 1.0.1-0.20250829075715-0deffcfc6bee or later

  ```sh
  go get github.com/mattermost/mattermost-plugin-github@v1.0.1-0.20250829075715-0deffcfc6bee
  ```

- github.com/mattermost/mattermost/server/v8 (Go): upgrade to 10.11.7-0.20251106103514-3b05384dd014 or later

  ```sh
  go get github.com/mattermost/mattermost/server/v8@v10.11.7-0.20251106103514-3b05384dd014
  ```


## Affected products

- github.com/mattermost/mattermost (Go) SEMVER:introduced=0,fixed=10.11.7-0.20251106103514-3b05384dd014, SEMVER:introduced=11.0.0-alpha.1+incompatible,fixed=11.1.0+incompatible
- github.com/mattermost/mattermost-plugin-github (Go) SEMVER:introduced=0,fixed=1.0.1-0.20250829075715-0deffcfc6bee
- github.com/mattermost/mattermost-server (Go) SEMVER:introduced=10.11.0-rc1+incompatible
- github.com/mattermost/mattermost-server/v5 (Go) SEMVER:introduced=0
- github.com/mattermost/mattermost-server/v6 (Go) SEMVER:introduced=0
- github.com/mattermost/mattermost/server/v8 (Go) SEMVER:introduced=0, SEMVER:introduced=10.11.0-rc1,fixed=10.11.7-0.20251106103514-3b05384dd014
- Mattermost Server

## Identifiers

- CVE-2025-13352
- GHSA-jf5h-xfw4-p8gp
- GO-2025-4247

## Related threats

- [Mattermost CSRF via Agents plugin mention reminder validation](https://junglewise.ai/threats/cve-2026-93851-mattermost-versions-11-9-x-11-9-1-11-8-x-11-8-5-11-7-x-11-7-10)
- [Mattermost denial of service via PDF text extraction memory exhaustion](https://junglewise.ai/threats/cve-2026-93850-mattermost-versions-11-9-x-11-9-1-11-8-x-11-8-5-11-7-x-11-7-10-11)
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- [Mattermost information disclosure in post deletion events](https://junglewise.ai/threats/cve-2026-19621-mattermost-versions-11-10-x-11-10-0-11-7-x-11-7-9-11-9-x-11-9-1)
- [Mattermost authentication token leak in server logs](https://junglewise.ai/threats/cve-2026-19600-mattermost-versions-11-9-x-11-9-1-11-8-x-11-8-5-11-7-x-11-7-10-11)