A memory corruption issue was addressed with improved input validation. This issue is fixed in macOS Big Sur 11.6, watchOS 8, tvOS 15, iOS 14.8 and iPadOS 14.8, iOS 15 and iPadOS 15. Processing a maliciously crafted image may lead to arbitrary code execution.
https://support.apple.com/kb/HT212953
https://support.apple.com/en-us/HT212819
https://support.apple.com/en-us/HT212815
https://support.apple.com/en-us/HT212814