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CVE-2026-13417 (GCVE-0-2026-13417)

Vulnerability from cvelistv5 – Published: 2026-09-14 10:44 – Updated: 2026-09-14 11:19
VLAI
Title
Boards plugin denial of service via unvalidated block fields.properties
Summary
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
Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-14 11:03 UTC
CWE
  • CWE-754 - Improper Check for Unusual or Exceptional Conditions
Assigner
References
URL Tags
https://mattermost.com/security-updates vendor-advisory
Impacted products
Vendor Product Version CPE status
Mattermost Mattermost Affected: 11.9.0 , ≤ 11.9.0 (semver)
Affected: 11.8.0 , ≤ 11.8.4 (semver)
Affected: 11.7.0 , ≤ 11.7.7 (semver)
Affected: 10.11.0 , ≤ 10.11.22 (semver)
Unaffected: 11.10.0
Unaffected: 11.9.1
Unaffected: 11.8.5
Unaffected: 11.7.8
Unaffected: 10.11.23
guessed Create a notification for this product.
Credits
alimursaliyev
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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