Discovery / credits: Malvuln - (c) 2021  
Original source:  
Threat: Trojan-Downloader.Win32.Delf.oxz  
Vulnerability: Insecure Permissions  
Description: Win32.Delf.oxz creates an 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: 373b1d95ccdbbc6531dff43bbbe43534  
Vuln ID: MVID-2021-0156  
Dropped files: winrao.exe  
Disclosure: 04/01/2021  
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 RECYCLER\  
Volume in drive C has no label.  
Directory of C:\RECYCLER  
0 File(s) 0 bytes  
C:\>attrib -s -h \RECYCLER\*  
C:\>dir RECYCLER\  
Volume in drive C has no label.  
Directory of C:\RECYCLER  
12/30/2019 02:34 AM 242,176 winrao.exe  
1 File(s) 242,176 bytes  
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