A logic issue was addressed with improved restrictions. This issue is fixed in tvOS 14.6, iOS 14.6 and iPadOS 14.6, Safari 14.1.1, macOS Big Sur 11.4, watchOS 7.5. A malicious website may be able to access restricted ports on arbitrary servers.
Exploitability
AV:NAC:LPR:NUI:RScope
S:UImpact
C:LI:LA:N5.4/CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N