smss.exe debugging subsystem in Windows NT and Windows 2000 does not properly authenticate programs that connect to other programs, which allows local users to gain administrator or SYSTEM privileges by duplicating a handle to a privileged process, as demonstrated by DebPloit.
Exploitability
AV:LAC:LPR:LUI:NScope
S:UImpact
C:HI:HA:H7.8/CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H