Description
Mattermost Desktop App versions <=5.13.0 fail to manage modals in the Mattermost Desktop App that stops a user with a server that uses basic authentication from accessing their server which allows an attacker that provides a malicious server to the user to deny use of the Desktop App via having the user configure the malicious server and forcing a modal popup that cannot be closed.
Affected products
mattermost: mattermost desktop
References1
- mattermost.com/security-updates Vendor Advisory
Metrics
- CVSS 3.1
-
6.1
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 25 · as of 9 November 2026
- CWE
- CWE-754
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