CVE-2026-12284Low· 3.7▾ SunlitMattermost 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 …
▾ Sunlit zone — Low / medium · no exploitation signal
impact 20.4 · likelihood 0 · exploitation 0
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Stakeholder-Specific Vulnerability Categorization from CISA's ADP record at CVE.org: whether exploitation is observed, whether an attack can be automated, and how much of the system is at stake.
Exploit-prediction probability, daily snapshots since Sep 18.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
0.1%
Last analysed / modified upstream
0.1% → 0.2%
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
mattermost_desktop >= 6.2.0, < 6.2.3Upgrade past the affected range:
mattermost_desktop 6.2.3Connected by shared product, vendor, weakness, or advisory.
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