cvedb.io
CVE-2026-4915
MEDIUM · CVSS 6.5
EPSS exploitation probability: 0%
Published 2026-05-25T08:16:24.897 · Last modified 2026-06-17T10:57:26.890

Summary

Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to filter nil elements from outgoing webhook attachment payloads before processing, which allows an authenticated user to cause a denial of service (server process termination) via a crafted webhook callback response containing a null attachment entry.. Mattermost Advisory ID: MMSA-2026-00641

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.