CVE-2026-12284

Mattermost Desktop App versions <=6.2 6.2.2.0 fails to validate the IPC sender in the leaveCall handler which allows a malicious or compromised Mattermost server (or a user with script access to a connected server view) to disconnect an active call belonging to a different connected server via the desktopAPI.leaveCall IPC message. Mattermost Advisory ID: MMSA-2026-00699

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

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)

cpe:2.3:a:mattermost:mattermost_desktop:*:*:*:*:*:*:*:*

History

13 Oct 2026, 12:04

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::::::::

17 Sep 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-17 16:17

Updated : 2026-10-13 12:04

NVD link : CVE-2026-12284

Mitre link : CVE-2026-12284

CVE.ORG link : CVE-2026-12284

JSON object : View

Products Affected

mattermost

mattermost_desktop

CWE

CWE-346

Origin Validation Error

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