A type confusion issue was addressed with improved checks. This issue is fixed in iOS 16.5.1 and iPadOS 16.5.1, iOS 15.7.7 and iPadOS 15.7.7, macOS Ventura 13.4.1, Safari 16.5.1. Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited.
https://support.apple.com/kb/HT213816
https://support.apple.com/kb/HT213814
https://support.apple.com/en-us/HT213816
https://support.apple.com/en-us/HT213814
https://support.apple.com/en-us/HT213813