CVE 2021-30720
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.
See the 
CVE page on Mitre.org
for more details.
