CISA description
If a Volume Shadow Copy (VSS) shadow copy of the system drive is available, users can read the SAM file which would allow any user to escalate privileges to SYSTEM level.
CVE-2021-36934
Microsoft · Windows
Microsoft Windows SAM Local Privilege Escalation Vulnerability
Required action
Apply updates per vendor instructions.
Notes & references
Where this lands in 800-53
Vulnerability data triggers these controls during assessment and continuous monitoring.