An out-of-bounds read was addressed with improved input validation. This issue is fixed in iOS 13.6 and iPadOS 13.6, tvOS 13.4.8, watchOS 6.2.8, Safari 13.1.2, iTunes 12.10.8 for Windows, iCloud for Windows 11.3, iCloud for Windows 7.20. A remote attacker may be able to cause unexpected application termination or arbitrary code execution.
https://support.apple.com/HT211295
https://support.apple.com/HT211294
https://support.apple.com/HT211293
https://support.apple.com/HT211292
https://support.apple.com/HT211291