CVE-2026-3471
Medium
Description
Mattermost Desktop App versions <=6.1 6.0.1 5.4.13.0 fail to prevent an invalid URL from loading in a pop-up window in the Mattermost Desktop App which allows a malicious server owner to repeated crash the application via calling {{window.open('javascript:alert()');}}. Mattermost Advisory ID: MMSA-2026-00618
SeverityMedium
CVSS6.5
Exploit probability—
Product
Mattermost Desktop
PublishedMay 18, 2026
First seenMay 18, 2026
Weakness typeCWE-939CWE-939
How to fix
Update
- mattermost mattermost_desktop6.2.0 or later
Vendor advisories
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mattermost mattermost_desktop | v ≤ 5.4.13.0, 6.0.0 ≤ v ≤ 6.0.1, 6.1.0 ≤ v < 6.2.0 | 6.2.0 |
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