CVE-2026-16047EPSS p17.5%

CVE-2026-16047CVE-2026-16047

mattermost / mattermost_server

Description

Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21, 11.8.x <= 11.8.3 fail to validate that users have read access to a channel before linking a board to it, which allows an authenticated attacker to discover the membership of private channels on the same team via creating, patching, importing, or bulk-creating boards with an arbitrary channelId. Mattermost Advisory ID: MMSA-2026-00674

Scoring

CVSS 4.3 ()
VectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
EPSS0.27% probability of exploitation · percentile 17.5% · 2026-10-05T12:00:23Z
Last modified2026-08-18
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.