CVE-2026-18223EPSS p4.8%

CVE-2026-18223CVE-2026-18223

Description

Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail to validate the invited recipient's email address when redeeming team and guest invitation tokens, which allows an authenticated attacker to join a team or gain unauthorized access to private channels via a forwarded or leaked invitation link.. Mattermost Advisory ID: MMSA-2026-00747

Scoring

CVSS 5.0 ()
VectorCVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:L/A:N
EPSS0.16% probability of exploitation · percentile 4.8% · 2026-10-17T12:00:28Z
Last modified2026-10-16
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.