Description
Mattermost Desktop App versions <= 5.13.0 fail to validate URLs external to the configured Mattermost servers, allowing an attacker on a server the user has configured to crash the user's application by sending the user a malformed URL.
Affected products
mattermost: mattermost desktop
References1
- mattermost.com/security-updates Vendor Advisory
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 23 · as of 9 November 2026
- CWE
- CWE-1287
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