Discovery / credits: Malvuln - (c) 2021  
Original source:  
Threat: Backdoor.Win32.RemoteManipulator.fdo  
Vulnerability: Insecure Permissions  
Description: The backdoor creates an insecure randomly named hidden dir with a .tmp ext E.g. 8RK86.tmp and grants change (C) permissions to the authenticated user group. Standard users can rename the malware and reboot to disable it or replace with their own executable to escalate privileges when a privileged user logs on to the infected machine.  
Type: PE32  
MD5: 66ef21e8d1cf30dce6e084a9e306c18f  
Vuln ID: MVID-2021-0116  
Dropped files: settings.dat, vp8encoder.dll, xpcomp.exe  
Disclosure: 03/01/2021  
C:\>cacls 4J83Z.tmp  
C:\4J83Z.tmp BUILTIN\Administrators:(OI)(CI)(ID)F  
NT AUTHORITY\Authenticated Users:(ID)C  
NT AUTHORITY\Authenticated Users:(OI)(CI)(IO)(ID)C  
C:\>cd 4J83Z.tmp  
Volume in drive C has no label.  
Directory of C:\4J83Z.tmp  
File Not Found  
C:\4J83Z.tmp>dir /a  
Volume in drive C has no label.  
Directory of C:\4J83Z.tmp  
02/25/2021 05:55 PM 2,664 settings.dat  
08/06/2017 06:51 AM 542,016 vp8encoder.dll  
02/25/2021 05:55 PM 2,981,888 xpcomp.exe  
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