A memory corruption issue was addressed with improved memory handling. This issue is fixed in macOS Catalina 10.15.1, Security Update 2019-001, and Security Update 2019-006, macOS Catalina 10.15, iOS 13. An application may be able to execute arbitrary code with system privileges.
CWE-787 - Out-of-Bounds Write
Out-of-bounds write vulnerability is a memory access bug that allows software to write data past the end or before the beginning of the intended buffer. This may result in the corruption of data, a crash, or arbitrary code execution.