CVE-2026-4643

Mattermost Desktop App versions <=6.1 6.0.1 5.4.13.0 fail to prevent server-rendered content from closing an underlying application view in the Mattermost Desktop App which allows a malicious server or plugin to crash the desktop client via invoking {{window.close()}} in the renderer context, leading to a denial of service condition at the client level. Mattermost Advisory ID: MMSA-2026-00633

CVSS v3 3.5 LOW

3.5^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.1 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

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, 17:44

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

18 May 2026, 09:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-18 09:16

Updated : 2026-06-17 10:56

NVD link : CVE-2026-4643

Mitre link : CVE-2026-4643

CVE.ORG link : CVE-2026-4643

JSON object : View

Products Affected

mattermost

mattermost_desktop

CWE

CWE-754

Improper Check for Unusual or Exceptional Conditions

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