Backdoor.Win32.Floder.gqe Insecure Permissions

`Discovery / credits: Malvuln - malvuln.com (c) 2021  
Original source: https://malvuln.com/advisory/0629e3b2ab8a973a3e37e4e97cb9cfea.txt  
Contact: [email protected]  
Media: twitter.com/malvuln  
  
Threat: Backdoor.Win32.Floder.gqe  
Vulnerability: Insecure Permissions  
Description: The malware creates an hidden insecure dir named "RECYCLER" 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: 0629e3b2ab8a973a3e37e4e97cb9cfea  
Vuln ID: MVID-2021-0200  
Dropped files: zaberg.exe, Desktop.ini  
Disclosure: 05/04/2021  
  
Exploit/PoC:  
C:\>cacls RECYCLER  
C:\RECYCLER 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 /a RECYCLER  
Volume in drive C has no label.  
  
Directory of C:\RECYCLER  
  
05/01/2021 11:11 PM <DIR> S-1-5-21-0243556031-888888379-781863308-1830  
0 File(s) 0 bytes  
3 Dir(s) 7,337,779,200 bytes free  
  
C:\>cd \RECYCLER\S-1-5-21-0243556031-888888379-781863308-1830  
  
C:\RECYCLER\S-1-5-21-0243556031-888888379-781863308-1830>dir /a  
Volume in drive C has no label.  
  
Directory of C:\RECYCLER\S-1-5-21-0243556031-888888379-781863308-1830  
  
05/01/2021 11:11 PM 63 Desktop.ini  
06/17/2012 02:46 AM 24,064 zaberg.exe  
2 File(s) 24,127 bytes  
  
  
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