CVE-2026-6343: Mattermost doesn't check public/private permissions

May 18, 2026 (updated June 1, 2026)

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to check public/private permissions which allows members without these permissions to access public playbooks via /get.. Mattermost Advisory ID: MMSA-2026-00591

References

github.com/advisories/GHSA-m79q-8qf5-v622
github.com/mattermost/mattermost-plugin-playbooks/commit/887d9cacb61655d40f20ad9d6e35b408a127c380
mattermost.com/security-updates
nvd.nist.gov/vuln/detail/CVE-2026-6343

Code Behaviors & Features

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