An issue was discovered in Mattermost Desktop App before 4.0.0. It mishandled the Same Origin Policy for setPermissionRequestHandler (e.g., video, audio, and notifications).
Severity
CVSS 3.1
5.3 medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS
0.8% chance of exploitation in the next 30 days; higher than 55% of CVEs (scores of 2026-10-31)