Backdoor.Win32.DarkKomet.artr Insecure Permissions

`Discovery / credits: Malvuln - malvuln.com (c) 2021  
Original source: https://malvuln.com/advisory/d2ee6046fd47de321d1310dccacca92b.txt  
Contact: [email protected]  
Media: twitter.com/malvuln  
  
Threat: Backdoor.Win32.DarkKomet.artr  
Vulnerability: Insecure Permissions  
Description: The malware creates an hidden insecure dir named "Windupdt" under c:\ drive and grants change (C) permissions to the authenticated user group. Standard users can rename the executables dropped by the malware to disable it or replace it with their own executable. Then wait for a privileged user to logon to the infected machine to potentially escalate privileges.  
Type: PE32  
MD5: d2ee6046fd47de321d1310dccacca92b  
Vuln ID: MVID-2021-0182  
Dropped files: winupdate.exe  
Disclosure: 04/21/2021  
  
  
Exploit/PoC:  
C:\>cacls Windupdt  
C:\Windupdt BUILTIN\Administrators:(OI)(CI)(ID)F  
NT AUTHORITY\SYSTEM:(OI)(CI)(ID)F  
BUILTIN\Users:(OI)(CI)(ID)R  
NT AUTHORITY\Authenticated Users:(ID)C  
NT AUTHORITY\Authenticated Users:(OI)(CI)(IO)(ID)C  
  
  
C:\>dir Windupdt  
Volume in drive C has no label.  
  
Directory of C:\Windupdt  
  
0 File(s) 0 bytes  
2 Dir(s) 34,641,420,288 bytes free  
  
  
C:\>attrib -s -h Windupdt/*  
  
C:\>dir Windupdt  
Volume in drive C has no label.  
  
Directory of C:\Windupdt  
  
06/15/2012 05:07 PM 650,752 winupdate.exe  
1 File(s) 650,752 bytes  
  
  
  
  
  
Disclaimer: The information contained within this advisory is supplied "as-is" with no warranties or guarantees of fitness of use or otherwise. Permission is hereby granted for the redistribution of this advisory, provided that it is not altered except by reformatting it, and that due credit is given. Permission is explicitly given for insertion in vulnerability databases and similar, provided that due credit is given to the author. The author is not responsible for any misuse of the information contained herein and accepts no responsibility for any damage caused by the use or misuse of this information. The author prohibits any malicious use of security related information or exploits by the author or elsewhere. Do not attempt to download Malware samples. The author of this website takes no responsibility for any kind of damages occurring from improper Malware handling or the downloading of ANY Malware mentioned on this website or elsewhere. All content Copyright (c) Malvuln.com (TM).  
`