CVE-2026-4858

Published May 21, 2026

Last updated 4 days ago

Overview

Description
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to check integration URL for path traversal which allows an malicious authenticated user to call an arbitrary API via system admin Mattermost auth token using via path traversal in integration action URL.. Mattermost Advisory ID: MMSA-2026-00640
Source
responsibledisclosure@mattermost.com
NVD status
Analyzed
Products
mattermost_server

Risk scores

CVSS 3.1

Type
Primary
Base score
9.9
Impact score
6
Exploitability score
3.1
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Severity
CRITICAL

Weaknesses

responsibledisclosure@mattermost.com
CWE-22

Social media

Hype score
Not currently trending

Configurations

References

Sources include official advisories and independent security research.