Backdoor.Win32.Plugx MVID-2024-0686 Insecure Permissions

`Discovery / credits: Malvuln (John Page aka hyp3rlinx) (c) 2024  
Original source: https://malvuln.com/advisory/eeb631127f1b9fb3d13d209d8e675634.txt  
Contact: [email protected]  
Media: x.com/malvuln   
  
Threat: Backdoor.Win32.Plugx  
Vulnerability: Insecure Permissions  
Family: Plugx  
Type: PE32  
MD5: eeb631127f1b9fb3d13d209d8e675634  
SHA256: c2804080c3f45e8232b3e955611f56c9ba513a7845ddad56a588c4191d139990  
Vuln ID: MVID-2024-0686  
Disclosure: 06/17/2024  
Description: The PlugX malware installs a service "McAfeeOEMInfoOME" which runs as SYSTEM. It also creates a hidden directory "TaskSchedulerome" under C:\ProgramData, granting full (F) permissions to the Everyone user group. Any user can replace the PE files 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.   
  
Exploit/PoC:  
cacls C:\ProgramData\TaskSchedulerome\mcf.exe  
ProgramData\TaskSchedulerome\mcf.exe Everyone:(OI)(CI)F  
  
attrib -s -h C:\ProgramData\TaskSchedulerome  
  
dir /a C:\ProgramData\TaskSchedulerome  
  
Directory of C:\ProgramData\TaskSchedulerome  
  
02/10/2018 01:21 AM 116,493 mcf.ep  
02/10/2018 01:21 AM 140,576 mcf.exe  
02/10/2018 01:21 AM 167,776,542 mcutil.dll  
3 File(s) 168,033,611 bytes  
2 Dir(s) 67,722,203,136 bytes free  
  
  
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