CVE-2026-6340EPSS p14.1%

CVE-2026-6340CVE-2026-6340

mattermost / mattermost_server

Description

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to validate 7zip archive structure before processing which allows an authenticated attacker to cause server memory exhaustion and denial of service via uploading a specially crafted 7zip file with excessive folder declarations.. Mattermost Advisory ID: MMSA-2026-00573

Scoring

CVSS 4.3 ()
VectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
EPSS0.24% probability of exploitation · percentile 14.1% · 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.