This issue was addressed with improved checks. This issue is fixed in macOS Big Sur 11.0.1, watchOS 7.0, iOS 14.0 and iPadOS 14.0, iCloud for Windows 7.21, tvOS 14.0. A remote attacker may be able to cause a denial of service.
seclists.org/fulldisclosure/2020/Dec/32
lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3E
support.apple.com/en-us/HT211843
support.apple.com/en-us/HT211844
support.apple.com/en-us/HT211847
support.apple.com/en-us/HT211850
support.apple.com/en-us/HT211931
support.apple.com/kb/HT211846