CVE-2026-4055
Insufficient permission validation on cross-team playbook run creation
CVSS Score
4.3
EPSS Score
0.0%
EPSS Percentile
0th
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
| CWE | CWE-863 |
| Vendor | mattermost |
| Product | mattermost |
| Published | May 21, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
None
Affected Versions
Mattermost / Mattermost
11.5.0 ≤ 11.5.1
Credits
0x7oda7123