CVE-2026-6517EPSS p8.3%

CVE-2026-6517CVE-2026-6517

mattermost / mattermost_desktop

Description

Mattermost Desktop App versions <=6.1 5.5.13.0 fail to restrict the allow list of domains to which NTLM credentials were forwarded to in the Mattermost Desktop App which allows any user on a server without the image proxy enabled to intercept other users credentials via embedding an image that routes to an external web server. Mattermost Advisory ID: MMSA-2026-00651

Scoring

CVSS 6.3 ()
VectorCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N
EPSS0.19% probability of exploitation · percentile 8.3% · 2026-06-19T12:03:05Z
Last modified2026-06-16
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.