CVE-2026-12284NVD

Vulnerability Summary

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

Severity Level

LOW(3.8)

Published Date

Sep 17, 2026

Last Modified

Sep 17, 2026

Exploitation Status

No confirmed exploitation yet

EPSS Score (30-Day)

0.13%Probability

Root Weakness (CWE)

CWE-346: Unknown/Unlisted Weakness ↗

Refer to the official MITRE database for detailed architectural specifications regarding this weakness.

CVSS v3.1 Base Metrics — Score 3.8 (LOW)

Attack VectorNetwork

Attack ComplexityHigh

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

ConfidentialityNone

IntegrityNone

AvailabilityLow

Affected & Patched Versions

Affected Versions

Mattermost Mattermost <= 6.2.2

Patched Versions

Mattermost Mattermost 6.2.2

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