remcos | 87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba

Modify Registry

description	ioc	Process
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\Userinit = "C:\\WINDOWS\\system32\\userinit.exe, \"C:\\Users\\Admin\\AppData\\Roaming\\remcos\\remcos.exe\""	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\Userinit = "C:\\WINDOWS\\system32\\userinit.exe, \"C:\\Users\\Admin\\AppData\\Roaming\\remcos\\remcos.exe\""	Dxpserver.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\Userinit = "C:\\WINDOWS\\system32\\userinit.exe, \"C:\\Users\\Admin\\AppData\\Roaming\\remcos\\remcos.exe\""	Dxpserver.exe

Remcos
Remcos is a closed-source remote control and surveillance software.
rat remcos
Remcos family
remcos

Checks computer location settings 2 TTPs 6 IoCs

Looks up country code configured in the registry, likely geofence.

Query Registry

T1012

System Information Discovery

T1082

description	ioc	Process
Key value queried	\REGISTRY\USER\S-1-5-21-2045521122-590294423-3465680274-1000\Control Panel\International\Geo\Nation	Dxpserver.exe
Key value queried	\REGISTRY\USER\S-1-5-21-2045521122-590294423-3465680274-1000\Control Panel\International\Geo\Nation	Dxpserver.exe
Key value queried	\REGISTRY\USER\S-1-5-21-2045521122-590294423-3465680274-1000\Control Panel\International\Geo\Nation	Dxpserver.exe
Key value queried	\REGISTRY\USER\S-1-5-21-2045521122-590294423-3465680274-1000\Control Panel\International\Geo\Nation	Dxpserver.exe
Key value queried	\REGISTRY\USER\S-1-5-21-2045521122-590294423-3465680274-1000\Control Panel\International\Geo\Nation	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe
Key value queried	\REGISTRY\USER\S-1-5-21-2045521122-590294423-3465680274-1000\Control Panel\International\Geo\Nation	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe

Executes dropped EXE 4 IoCs

pid	Process
2008	Dxpserver.exe
1432	Dxpserver.exe
4812	Dxpserver.exe
2428	Dxpserver.exe

Adds Run key to start application 2 TTPs 3 IoCs

persistence

Registry Run Keys / Startup Folder

T1547.001

Modify Registry

description	ioc	Process
Set value (str)	\REGISTRY\USER\S-1-5-21-2045521122-590294423-3465680274-1000\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\remcos = "\"C:\\Users\\Admin\\AppData\\Roaming\\remcos\\remcos.exe\""	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe
Set value (str)	\REGISTRY\USER\S-1-5-21-2045521122-590294423-3465680274-1000\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\remcos = "\"C:\\Users\\Admin\\AppData\\Roaming\\remcos\\remcos.exe\""	Dxpserver.exe
Set value (str)	\REGISTRY\USER\S-1-5-21-2045521122-590294423-3465680274-1000\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\remcos = "\"C:\\Users\\Admin\\AppData\\Roaming\\remcos\\remcos.exe\""	Dxpserver.exe

Modifies WinLogon 2 TTPs 3 IoCs

persistence

Winlogon Helper DLL

Modify Registry

description	ioc	Process
Key created	\REGISTRY\MACHINE\Software\WOW6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe
Key created	\REGISTRY\MACHINE\Software\WOW6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\	Dxpserver.exe
Key created	\REGISTRY\MACHINE\Software\WOW6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\	Dxpserver.exe

AutoIT Executable 1 IoCs

AutoIT scripts compiled to PE executables.

resource	yara_rule
behavioral2/files/0x0007000000023c96-15.dat	autoit_exe

Suspicious use of SetThreadContext 3 IoCs

description	pid	Process	procid_target
PID 2808 set thread context of 4652	2808	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe	83
PID 2008 set thread context of 1432	2008	Dxpserver.exe	102
PID 4812 set thread context of 2428	4812	Dxpserver.exe	109

Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s).

System Information Discovery
T1082

System Location Discovery: System Language Discovery 1 TTPs 12 IoCs

Attempt gather information about the system language of a victim in order to infer the geographical location of that host.

discovery

System Language Discovery

T1614.001

description	ioc	Process
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	WScript.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	schtasks.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	Dxpserver.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	WScript.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	Dxpserver.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	Dxpserver.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	WScript.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	Dxpserver.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	schtasks.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	schtasks.exe

Modifies registry class 3 IoCs

description	ioc	Process
Key created	\REGISTRY\USER\S-1-5-21-2045521122-590294423-3465680274-1000_Classes\Local Settings	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe
Key created	\REGISTRY\USER\S-1-5-21-2045521122-590294423-3465680274-1000_Classes\Local Settings	Dxpserver.exe
Key created	\REGISTRY\USER\S-1-5-21-2045521122-590294423-3465680274-1000_Classes\Local Settings	Dxpserver.exe

Scheduled Task/Job: Scheduled Task 1 TTPs 3 IoCs

Schtasks is often used by malware for persistence or to perform post-infection execution.

persistence execution

Scheduled Task

pid	Process
220	schtasks.exe
4212	schtasks.exe
1104	schtasks.exe

Suspicious use of WriteProcessMemory 33 IoCs

description	pid	Process	procid_target
PID 2808 wrote to memory of 4652	2808	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe	83
PID 2808 wrote to memory of 4652	2808	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe	83
PID 2808 wrote to memory of 4652	2808	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe	83
PID 2808 wrote to memory of 4652	2808	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe	83
PID 2808 wrote to memory of 4652	2808	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe	83
PID 4652 wrote to memory of 3608	4652	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe	84
PID 4652 wrote to memory of 3608	4652	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe	84
PID 4652 wrote to memory of 3608	4652	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe	84
PID 2808 wrote to memory of 220	2808	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe	97
PID 2808 wrote to memory of 220	2808	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe	97
PID 2808 wrote to memory of 220	2808	87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe	97
PID 2008 wrote to memory of 1432	2008	Dxpserver.exe	102
PID 2008 wrote to memory of 1432	2008	Dxpserver.exe	102
PID 2008 wrote to memory of 1432	2008	Dxpserver.exe	102
PID 2008 wrote to memory of 1432	2008	Dxpserver.exe	102
PID 2008 wrote to memory of 1432	2008	Dxpserver.exe	102
PID 1432 wrote to memory of 2068	1432	Dxpserver.exe	103
PID 1432 wrote to memory of 2068	1432	Dxpserver.exe	103
PID 1432 wrote to memory of 2068	1432	Dxpserver.exe	103
PID 2008 wrote to memory of 4212	2008	Dxpserver.exe	106
PID 2008 wrote to memory of 4212	2008	Dxpserver.exe	106
PID 2008 wrote to memory of 4212	2008	Dxpserver.exe	106
PID 4812 wrote to memory of 2428	4812	Dxpserver.exe	109
PID 4812 wrote to memory of 2428	4812	Dxpserver.exe	109
PID 4812 wrote to memory of 2428	4812	Dxpserver.exe	109
PID 4812 wrote to memory of 2428	4812	Dxpserver.exe	109
PID 4812 wrote to memory of 2428	4812	Dxpserver.exe	109
PID 2428 wrote to memory of 704	2428	Dxpserver.exe	110
PID 2428 wrote to memory of 704	2428	Dxpserver.exe	110
PID 2428 wrote to memory of 704	2428	Dxpserver.exe	110
PID 4812 wrote to memory of 1104	4812	Dxpserver.exe	112
PID 4812 wrote to memory of 1104	4812	Dxpserver.exe	112
PID 4812 wrote to memory of 1104	4812	Dxpserver.exe	112

C:\Users\Admin\AppData\Local\Temp\87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe
"C:\Users\Admin\AppData\Local\Temp\87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe"
1⤵
- Checks computer location settings
- Suspicious use of SetThreadContext
- System Location Discovery: System Language Discovery
- Suspicious use of WriteProcessMemory
PID:2808
- C:\Users\Admin\AppData\Local\Temp\87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe
  "C:\Users\Admin\AppData\Local\Temp\87d7c77548cb9ed812e637760de0a6c97afa4b8f11cca0f374f7adc6f8e257ba.exe"
  2⤵
  - Modifies WinLogon for persistence
  - Checks computer location settings
  - Adds Run key to start application
  - Modifies WinLogon
  - System Location Discovery: System Language Discovery
  - Modifies registry class
  - Suspicious use of WriteProcessMemory
  PID:4652
- - C:\Windows\SysWOW64\WScript.exe
    "C:\Windows\System32\WScript.exe" "C:\Users\Admin\AppData\Local\Temp\install.vbs"
    3⤵
    - System Location Discovery: System Language Discovery
    PID:3608
- C:\Windows\SysWOW64\schtasks.exe
  "C:\Windows\SysWOW64\schtasks.exe" /create /tn cttunesvr /tr "C:\Users\Admin\AppData\Roaming\adprovider\Dxpserver.exe" /sc minute /mo 1 /F
  2⤵
  - System Location Discovery: System Language Discovery
  - Scheduled Task/Job: Scheduled Task
  PID:220

C:\Users\Admin\AppData\Roaming\adprovider\Dxpserver.exe
C:\Users\Admin\AppData\Roaming\adprovider\Dxpserver.exe
1⤵
- Checks computer location settings
- Executes dropped EXE
- Suspicious use of SetThreadContext
- System Location Discovery: System Language Discovery
- Suspicious use of WriteProcessMemory
PID:2008
- C:\Users\Admin\AppData\Roaming\adprovider\Dxpserver.exe
  "C:\Users\Admin\AppData\Roaming\adprovider\Dxpserver.exe"
  2⤵
  - Modifies WinLogon for persistence
  - Checks computer location settings
  - Executes dropped EXE
  - Adds Run key to start application
  - Modifies WinLogon
  - System Location Discovery: System Language Discovery
  - Modifies registry class
  - Suspicious use of WriteProcessMemory
  PID:1432
- - C:\Windows\SysWOW64\WScript.exe
    "C:\Windows\System32\WScript.exe" "C:\Users\Admin\AppData\Local\Temp\install.vbs"
    3⤵
    - System Location Discovery: System Language Discovery
    PID:2068
- C:\Windows\SysWOW64\schtasks.exe
  "C:\Windows\SysWOW64\schtasks.exe" /create /tn cttunesvr /tr "C:\Users\Admin\AppData\Roaming\adprovider\Dxpserver.exe" /sc minute /mo 1 /F
  2⤵
  - System Location Discovery: System Language Discovery
  - Scheduled Task/Job: Scheduled Task
  PID:4212

C:\Users\Admin\AppData\Roaming\adprovider\Dxpserver.exe
C:\Users\Admin\AppData\Roaming\adprovider\Dxpserver.exe
1⤵
- Checks computer location settings
- Executes dropped EXE
- Suspicious use of SetThreadContext
- System Location Discovery: System Language Discovery
- Suspicious use of WriteProcessMemory
PID:4812
- C:\Users\Admin\AppData\Roaming\adprovider\Dxpserver.exe
  "C:\Users\Admin\AppData\Roaming\adprovider\Dxpserver.exe"
  2⤵
  - Modifies WinLogon for persistence
  - Checks computer location settings
  - Executes dropped EXE
  - Adds Run key to start application
  - Modifies WinLogon
  - System Location Discovery: System Language Discovery
  - Modifies registry class
  - Suspicious use of WriteProcessMemory
  PID:2428
- - C:\Windows\SysWOW64\WScript.exe
    "C:\Windows\System32\WScript.exe" "C:\Users\Admin\AppData\Local\Temp\install.vbs"
    3⤵
    - System Location Discovery: System Language Discovery
    PID:704
- C:\Windows\SysWOW64\schtasks.exe
  "C:\Windows\SysWOW64\schtasks.exe" /create /tn cttunesvr /tr "C:\Users\Admin\AppData\Roaming\adprovider\Dxpserver.exe" /sc minute /mo 1 /F
  2⤵
  - System Location Discovery: System Language Discovery
  - Scheduled Task/Job: Scheduled Task
  PID:1104

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Scheduled Task/Job

T1053

Scheduled Task

Persistence

Boot or Logon Autostart Execution

T1547

Registry Run Keys / Startup Folder

T1547.001

Winlogon Helper DLL

Scheduled Task/Job

T1053

Scheduled Task

Privilege Escalation

Boot or Logon Autostart Execution

T1547

Registry Run Keys / Startup Folder

T1547.001

Winlogon Helper DLL

Scheduled Task/Job

T1053

Scheduled Task

Defense Evasion

Modify Registry