Mattermost allows an unauthorized Guest user access to Playbook

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

4.3 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

EPSS

• CVE-2025-3228: 0.29% estimated exploitation activity in the next 30 days; percentile 22.14 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Mattermost versions 10.5.x <= 10.5.5, 9.11.x <= 9.11.15, 10.8.x <= 10.8.0, 10.7.x <= 10.7.2, 10.6.x <= 10.6.5 fail to properly retrieve requestorInfo from playbooks handler for guest users which allows an attacker access to the playbook run.

Published by the source

20 Jun 2025, 15:30 UTC

Last modified by the source

20 Jun 2025, 18:08 UTC

Source last checked

26 Oct 2026, 15:09 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-4578-6gjh-f2jm

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# Patch Next advisory brief: CVE-2025-3228

Advisory: Mattermost allows an unauthorized Guest user access to Playbook
IDs: CVE-2025-3228, GHSA-4578-6gjh-f2jm
Record: https://patchnext.com/advisories/cve-2025-3228 (revision 1, source checked 26 Oct 2026, 15:09 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 4.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/mattermost/mattermost/server/v8 10.8.1, 10.7.3, 10.6.6, 10.5.6, 9.11.16, 8.0.0-20250520060012-d0380305ef7a; github.com/mattermost/mattermost-server 0.0.0-20250520060012-d0380305ef7a. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/mattermost/mattermost/server/v8: affected < 8.0.0-20250520060012-d0380305ef7a; >= 10.5.0, <= 10.5.5; >= 9.11.0, <= 9.11.15; >= 10.8.0, <= 10.8.0; >= 10.7.0, <= 10.7.2; >= 10.6.0, <= 10.6.5; fixed in 9.11.16, 10.5.6, 10.8.1, 10.7.3, 10.6.6, 8.0.0-20250520060012-d0380305ef7a
- Go github.com/mattermost/mattermost-server: affected < 0.0.0-20250520060012-d0380305ef7a; fixed in 0.0.0-20250520060012-d0380305ef7a

## Suggested inspection (read-only)
- Go github.com/mattermost/mattermost/server/v8: check the installed version with your package manager.
- Go github.com/mattermost/mattermost-server: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/mattermost/mattermost/server/v8, github.com/mattermost/mattermost-server.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-4578-6gjh-f2jm (GitHub-reviewed advisory GHSA-4578-6gjh-f2jm lists affected ranges: Go github.com/mattermost/mattermost-server >=0 =0 =10.5.0 =9.11.0 =10.8.0 =10.7.0 =10.6.0 <=10.6.5)

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