CVE-2026-4055

May 21, 2026, 7:45 p.m.

4.3
Medium

Description

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

Product(s) Impacted

Vendor Product Versions
Mattermost
  • Mattermost Server
  • *

Weaknesses

Common security weaknesses mapped to this vulnerability.

CWE-863
Incorrect Authorization
The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions.

*CPE(s)

Affected systems and software identified for this CVE.

Type Vendor Product Version Update Edition Language Software Edition Target Software Target Hardware Other Information
a mattermost mattermost_server / / / / / / / /
a mattermost mattermost_server / / / / / / / /
a mattermost mattermost_server / / / / / / / /

CVSS Score

4.3 / 10

CVSS Data - 3.1

  • Attack Vector: NETWORK
  • Attack Complexity: LOW
  • Privileges Required: LOW
  • Scope: UNCHANGED
  • Confidentiality Impact: NONE
  • Integrity Impact: LOW
  • Availability Impact: NONE
  • CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

    View Vector String

Timeline

Published: May 21, 2026, 8:16 a.m.
Last Modified: May 21, 2026, 7:45 p.m.

Status : Analyzed

CVE has been recently published to the CVE List and has been received by the NVD.

More info

*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.