CVE-2026-13426

Medium

Description

The Mattermost Go module github.com/mattermost/mattermost/server/public versions < v0.1.22 fail to validate path parameters when constructing API route paths which allows an attacker to redirect API calls to unintended endpoints via crafted IDs containing path traversal components. Mattermost Advisory ID: MMSA-2025-00532

SeverityMedium

CVSS5.4

Exploit probability—

ProductGithub.com/mattermost/mattermost/server/public

PublishedJun 26, 2026

First seenJun 26, 2026

Weakness typeCWE-22Path traversal

How to fix

Update

github.com/mattermost/mattermost/server/public0.1.22 or later

Vendor advisories

mattermost.com/security-updates

Affected products

Product	Affected versions	Fixed in
github.com/mattermost/mattermost/server/publicGo	v < 0.1.22	0.1.22

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