cvedb.io
CVE-2026-5139
MEDIUM · CVSS 5.4
EPSS exploitation probability: 0%
Published 2026-06-22T14:17:50.887 · Last modified 2026-06-23T20:50:51.550

Summary

Mattermost versions 11.7.x <= 11.7.0, 11.6.x <= 11.6.2, 11.5.x <= 11.5.5, 10.11.x <= 10.11.17 fail to enforce administrator authorization on the {{setDefaultInstance}} call within the {{/gitlab connect}} command handler, which allows any authenticated user to overwrite the global default GitLab instance configuration via the {{/gitlab connect <instance-name>}} slash command.. Mattermost Advisory ID: MMSA-2026-00644

Affected products

mattermost — mattermost_server

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.