CVE-2026-13426

Client4 fails to validate path parameters

Published Jun 26, 2026 CVSS 3.1 · 5.4 Medium EPSS < 1% KEV · Not listed
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

Remediation

Vendor Solution

Update the github.com/mattermost/mattermost/server/public module to v0.1.22 or higher.

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-72v2-v53v-4qmm github.com/mattermost/mattermost/server/public vulnerable to path traversal in API route construction
References
History
Type Values Removed Values Added
First Time appeared Mattermost
Mattermost mattermost Server
Vendors & Products Mattermost
Mattermost mattermost Server
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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
Title Client4 fails to validate path parameters
Weaknesses CWE-22
References
Metrics cvssV3_1

{'score': 5.4, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
Mattermost
Published
Updated
Jun 26, 2026, 2:39 PM
Reserved
Jun 26, 2026, 1:32 PM
Status
Awaiting Analysis
Published
Jun 26, 2026, 2:17 PM
Modified
Oct 25, 2026, 10:10 PM