An out-of-bounds read was addressed with improved input validation. This issue is fixed in iOS 14.8 and iPadOS 14.8, tvOS 15, watchOS 8, iOS 15 and iPadOS 15. Processing a maliciously crafted audio file may disclose restricted memory.
https://support.apple.com/kb/HT212869
https://support.apple.com/kb/HT212816
https://support.apple.com/en-us/HT212819
https://support.apple.com/en-us/HT212815
https://support.apple.com/en-us/HT212814