CVE-2026-4055 (GCVE-0-2026-4055)

Vulnerability from cvelistv5 – Published: 2026-05-21 07:13 – Updated: 2026-05-21 12:39
VLAI
Title
Insufficient permission validation on cross-team playbook run creation
Summary
Mattermost versions 11.5.x <= 11.5.1 fail to validate team-level run_create permission against the target team when creating a playbook run which allows an authenticated team member to create runs in teams where they lack permission via specifying a different team ID in the run creation API request. Mattermost Advisory ID: MMSA-2026-00629
Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-863 - Incorrect Authorization
Assigner
References
URL Tags
https://mattermost.com/security-updates vendor-advisory
Impacted products
Vendor Product Version
Mattermost Mattermost Affected: 11.5.0 , ≤ 11.5.1 (semver)
Unaffected: 11.6.0
Unaffected: 11.5.2
Unaffected: 10.11.14
Unaffected: 11.4.4
Create a notification for this product.
Credits
0x7oda7123
Show details on NVD website
To clipboard 

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


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