CVE-2026-4055

Published May 21, 2026

Last updated 4 days ago

Overview

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
Source
responsibledisclosure@mattermost.com
NVD status
Analyzed
Products
mattermost_server

Risk scores

CVSS 3.1

Type
Secondary
Base score
4.3
Impact score
1.4
Exploitability score
2.8
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Severity
MEDIUM

Weaknesses

responsibledisclosure@mattermost.com
CWE-863

Social media

Hype score
Not currently trending

Configurations

References

Sources include official advisories and independent security research.