A memory corruption issue was addressed with improved memory handling. This issue is fixed in iOS 13.3 and iPadOS 13.3, watchOS 6.1.1, macOS Catalina 10.15.2, Security Update 2019-002 Mojave, and Security Update 2019-007 High Sierra, tvOS 13.3. An application may be able to execute arbitrary code with system privileges.
https://support.apple.com/en-us/HT210790
https://support.apple.com/en-us/HT210789