A logic issue was addressed with improved state management. This issue is fixed in iOS 14.8 and iPadOS 14.8, tvOS 15, iOS 15 and iPadOS 15, watchOS 8, Security Update 2021-007 Catalina. Processing a malicious audio file may result in unexpected application termination or arbitrary code execution.
https://support.apple.com/kb/HT212804
https://support.apple.com/en-us/HT212871
https://support.apple.com/en-us/HT212819
https://support.apple.com/en-us/HT212815