CVE-2026-3471

Mattermost Desktop App versions <=6.1 6.0.1 5.4.13.0 fail to prevent an invalid URL from loading in a pop-up window in the Mattermost Desktop App which allows a malicious server owner to repeated crash the application via calling {{window.open('javascript:alert()');}}. Mattermost Advisory ID: MMSA-2026-00618

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://mattermost.com/security-updates	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mattermost:mattermost_desktop::::::::
	cpe:2.3:a:mattermost:mattermost_desktop::::::::
	cpe:2.3:a:mattermost:mattermost_desktop::::::::

History

05 Jun 2026, 17:43

Type	Values Removed	Values Added
First Time		Mattermost Mattermost mattermost Desktop
References	~~() https://mattermost.com/security-updates -~~	() https://mattermost.com/security-updates - Vendor Advisory
CPE		cpe:2.3:a:mattermost:mattermost_desktop::::::::

18 May 2026, 09:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-18 09:16

Updated : 2026-06-17 10:43

NVD link : CVE-2026-3471

Mitre link : CVE-2026-3471

CVE.ORG link : CVE-2026-3471

JSON object : View

Products Affected

mattermost

mattermost_desktop

CWE

CWE-939

Improper Authorization in Handler for Custom URL Scheme

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