VULNERABILITY INTELLIGENCE

CVE-2026-3115

CVSS score4.3 MEDIUM
EPSS probability0.24%
CISA KEVNot currently listed
Published2026-03-26
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Description

Mattermost versions 11.2.x <= 11.2.2, 10.11.x <= 10.11.10, 11.4.x <= 11.4.0, 11.3.x <= 11.3.1 fail to apply view restrictions when retrieving group member IDs, which allows authenticated guest users to enumerate user IDs outside their allowed visibility scope via the group retrieval endpoint.. Mattermost Advisory ID: MMSA-2026-00594

Weakness classification

  • CWE-863: Incorrect Authorization

Primary references