CVE-2026-8683

Mattermost Desktop App versions <=6.1 5.5.13.0 fail to account for attempting to open extremely long URLs in the Mattermost Desktop App which allows a malicious server owner to crash the application via including a script to call window.open on a very large URL. Mattermost Advisory ID: MMSA-2026-00652

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::::::::

History

16 Jun 2026, 17:18

Type	Values Removed	Values Added
CPE		cpe:2.3:a:mattermost:mattermost_desktop:::::::: 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

15 Jun 2026, 16:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-15 16:16

Updated : 2026-06-17 11:04

NVD link : CVE-2026-8683

Mitre link : CVE-2026-8683

CVE.ORG link : CVE-2026-8683

JSON object : View

Products Affected

mattermost

mattermost_desktop

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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