CVE-2026-9602

Mattermost Desktop App versions <=6.2 6.0.2 5.6.13.0 fail to validate payloads sent from the Mattermost Web App to the Desktop App which allows a malicious server owner to crash the Mattermost Desktop App via changing the payload of a method to a malformed one. Mattermost Advisory ID: MMSA-2026-00678

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 LOW

User Interaction NONE

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

30 Jul 2026, 14:38

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

17 Jul 2026, 11:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-17 11:17

Updated : 2026-07-30 14:38

NVD link : CVE-2026-9602

Mitre link : CVE-2026-9602

CVE.ORG link : CVE-2026-9602

JSON object : View

Products Affected

mattermost

mattermost_desktop

CWE

CWE-400

Uncontrolled Resource Consumption

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