CVE-2026-6333EPSS p2.8%

CVE-2026-6333CVE-2026-6333

mattermost / mattermost_server

Description

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to validate the Host header when constructing response URLs for custom slash commands which allows an authenticated attacker to redirect slash command responses to an attacker-controlled server via a spoofed Host header.. Mattermost Advisory ID: MMSA-2026-00582

Scoring

CVSS 3.5 ()
VectorCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:N
EPSS0.14% probability of exploitation · percentile 2.8% · 2026-10-17T12:00:28Z
Last modified2026-10-14
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.