Discovery / credits: Malvuln - (c) 2021  
Original source:  
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  
C:\>cacls RECYCLER  
C:\RECYCLER BUILTIN\Administrators:(OI)(CI)(ID)F  
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  
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) (TM).