VULNERABILITY INTELLIGENCE

CVE-2026-9708

CVSS score4.9 MEDIUM
EPSS probability0.36%
CISA KEVNot currently listed
Published2026-07-13
Last modified2026-07-13
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N

Description

Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to validate that an assigned incoming webhook user has access to the target team or channel, which allows a requester with webhook management permissions to create posts or direct messages attributed to another user via crafted incoming webhook configuration and payloads.. Mattermost Advisory ID: MMSA-2026-00683

Weakness classification

  • CWE-639: Authorization Bypass Through User-Controlled Key

Primary references