CVE-2026-13417

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

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://mattermost.com/security-updates

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-14 11:17

Updated : 2026-09-14 12:17

NVD link : CVE-2026-13417

Mitre link : CVE-2026-13417

CVE.ORG link : CVE-2026-13417

JSON object : View

Products Affected

No product.

CWE

CWE-754

Improper Check for Unusual or Exceptional Conditions

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