cbcvebase.
CVE-2026-8683
published 2026-06-15

CVE-2026-8683: Mattermost Desktop App versions <=6.1 5.5.13.0 fail to account for attempting to open extremely long URLs in the Mattermost Desktop App which allows a…

PriorityP431medium6.5CVSS 3.1
AVNACLPRNUIRSUCNINAH
EPSS
0.20%
9.9th percentile
Mattermost Desktop App versions <=6.1 5.5.13.0 fail to account for attempting to open extremely long URLs in the Mattermost Desktop App which allows a malicious server owner to crash the application via including a script to call window.open on a very large URL. Mattermost Advisory ID: MMSA-2026-00652

Affected

3 ranges
VendorProductVersion rangeFixed in
mattermostmattermost<= 5.5.13
mattermostmattermost_desktop<= 5.13.0
mattermostmattermost_desktop6.1.0 – 6.1.5
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