A logic issue existed resulting in memory corruption. This was addressed with improved state management. This issue is fixed in macOS Big Sur 11.0.1. An application may be able to execute arbitrary code with kernel privileges.
http://seclists.org/fulldisclosure/2021/Feb/14
http://seclists.org/fulldisclosure/2020/Dec/32
https://support.apple.com/kb/HT212147
https://support.apple.com/en-us/HT211931
Source: Mitre, NVD
Published: 2020-12-08
Updated: 2021-02-10
Base Score: 9.3
Vector: CVSS2#AV:N/AC:M/Au:N/C:C/I:C/A:C
Severity: High
Base Score: 7.8
Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS: 0.11475