CVE-2026-13417

Boards plugin denial of service via unvalidated block fields.properties

CVSS 3.1 4.3 MEDIUMCheck source for fixed versionsKEV status unknown

Original advisory

cve-program · CVE-2026-13417

Published

Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7, 10.11.x <= 10.11.22 fail to validate the type of `fields.properties` on block creation which allows an authenticated user with editor access to a board to crash the Boards plugin worker and trigger a denial of service via a child block whose `fields.properties` is a non-object value. Mattermost Advisory ID: MMSA-2026-00710

Read the publisher's advisory

Affected versions, risk and source history

Exploitation and risk

Source status

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cve-program · CVE-2026-13417

Published

Boards plugin denial of service via unvalidated block fields.properties

Source published: 14 Sep 2026 10:44:59 UTC
Source modified: 14 Sep 2026 11:19:44 UTC
Saved here: 23 Oct 2026 15:48:27 UTC
Source terms: CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

Source: cve-program · CVE Program Terms of Use. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

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