CVE-2026-26230 (GCVE-0-2026-26230)

Vulnerability from cvelistv5 – Published: 2026-03-16 20:19 – Updated: 2026-03-17 13:37
VLAI
Title
Team Admin Privilege Escalation to Demote Members to Guest
Summary
Mattermost versions 10.11.x <= 10.11.10 fail to properly validate permission requirements in the team member roles API endpoint which allows team administrators to demote members to guest role. Mattermost Advisory ID: MMSA-2025-00531
Severity
3.8 (Low)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N
CWE
  • CWE-863 - Incorrect Authorization
Assigner
References
URL Tags
https://mattermost.com/security-updates vendor-advisory
Impacted products
Vendor Product Version
Mattermost Mattermost Affected: 10.11.0 , ≤ 10.11.10 (semver)
Unaffected: 11.4.0
Unaffected: 10.11.11
Create a notification for this product.
Credits
hackit_bharat
Show details on NVD website
To clipboard 

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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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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
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