remcos | 77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f

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\""	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.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 4 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-1-5-21-3442511616-637977696-3186306149-1000\Control Panel\International\Geo\Nation	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe
Key value queried	\REGISTRY\USER\S-1-5-21-3442511616-637977696-3186306149-1000\Control Panel\International\Geo\Nation	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe
Key value queried	\REGISTRY\USER\S-1-5-21-3442511616-637977696-3186306149-1000\Control Panel\International\Geo\Nation	Dxpserver.exe
Key value queried	\REGISTRY\USER\S-1-5-21-3442511616-637977696-3186306149-1000\Control Panel\International\Geo\Nation	Dxpserver.exe

Executes dropped EXE 2 IoCs

pid	Process
3912	Dxpserver.exe
3164	Dxpserver.exe

Adds Run key to start application 2 TTPs 2 IoCs

persistence

Registry Run Keys / Startup Folder

T1547.001

Modify Registry

description	ioc	Process
Set value (str)	\REGISTRY\USER\S-1-5-21-3442511616-637977696-3186306149-1000\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\remcos = "\"C:\\Users\\Admin\\AppData\\Roaming\\remcos\\remcos.exe\""	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe
Set value (str)	\REGISTRY\USER\S-1-5-21-3442511616-637977696-3186306149-1000\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\remcos = "\"C:\\Users\\Admin\\AppData\\Roaming\\remcos\\remcos.exe\""	Dxpserver.exe

Modifies WinLogon 2 TTPs 2 IoCs

persistence

Winlogon Helper DLL

Modify Registry

description	ioc	Process
Key created	\REGISTRY\MACHINE\Software\WOW6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.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/0x0007000000023cb6-15.dat	autoit_exe

Suspicious use of SetThreadContext 2 IoCs

description	pid	Process	procid_target
PID 1788 set thread context of 3572	1788	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe	82
PID 3912 set thread context of 3164	3912	Dxpserver.exe	96

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 8 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	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe
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	Dxpserver.exe
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	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe

Modifies registry class 2 IoCs

description	ioc	Process
Key created	\REGISTRY\USER\S-1-5-21-3442511616-637977696-3186306149-1000_Classes\Local Settings	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe
Key created	\REGISTRY\USER\S-1-5-21-3442511616-637977696-3186306149-1000_Classes\Local Settings	Dxpserver.exe

Scheduled Task/Job: Scheduled Task 1 TTPs 2 IoCs

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

persistence execution

Scheduled Task

pid	Process
680	schtasks.exe
4720	schtasks.exe

Suspicious use of WriteProcessMemory 22 IoCs

description	pid	Process	procid_target
PID 1788 wrote to memory of 3572	1788	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe	82
PID 1788 wrote to memory of 3572	1788	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe	82
PID 1788 wrote to memory of 3572	1788	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe	82
PID 1788 wrote to memory of 3572	1788	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe	82
PID 1788 wrote to memory of 3572	1788	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe	82
PID 3572 wrote to memory of 800	3572	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe	83
PID 3572 wrote to memory of 800	3572	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe	83
PID 3572 wrote to memory of 800	3572	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe	83
PID 1788 wrote to memory of 680	1788	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe	91
PID 1788 wrote to memory of 680	1788	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe	91
PID 1788 wrote to memory of 680	1788	77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe	91
PID 3912 wrote to memory of 3164	3912	Dxpserver.exe	96
PID 3912 wrote to memory of 3164	3912	Dxpserver.exe	96
PID 3912 wrote to memory of 3164	3912	Dxpserver.exe	96
PID 3912 wrote to memory of 3164	3912	Dxpserver.exe	96
PID 3912 wrote to memory of 3164	3912	Dxpserver.exe	96
PID 3164 wrote to memory of 4540	3164	Dxpserver.exe	97
PID 3164 wrote to memory of 4540	3164	Dxpserver.exe	97
PID 3164 wrote to memory of 4540	3164	Dxpserver.exe	97
PID 3912 wrote to memory of 4720	3912	Dxpserver.exe	98
PID 3912 wrote to memory of 4720	3912	Dxpserver.exe	98
PID 3912 wrote to memory of 4720	3912	Dxpserver.exe	98

C:\Users\Admin\AppData\Local\Temp\77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe
"C:\Users\Admin\AppData\Local\Temp\77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe"
1⤵
- Checks computer location settings
- Suspicious use of SetThreadContext
- System Location Discovery: System Language Discovery
- Suspicious use of WriteProcessMemory
PID:1788
- C:\Users\Admin\AppData\Local\Temp\77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.exe
  "C:\Users\Admin\AppData\Local\Temp\77c86730a3bd4ff9551db5a55053370d5f34453f95a3da5c45a19c5174f1379f.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:3572
- - 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:800
- 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:680

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:3912
- 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:3164
- - 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:4540
- 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:4720

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Scheduled Task/Job

T1053

Scheduled Task

Persistence

Boot or Logon Autostart Execution

3

T1547

Registry Run Keys / Startup Folder

T1547.001

Winlogon Helper DLL

2

Scheduled Task/Job

T1053

Scheduled Task

Privilege Escalation

Boot or Logon Autostart Execution

3

T1547

Registry Run Keys / Startup Folder

T1547.001

Winlogon Helper DLL

2

Scheduled Task/Job

T1053

Scheduled Task

Defense Evasion

Modify Registry

3

Credential Access

Discovery

Query Registry

T1012

System Information Discovery

2

T1082

System Location Discovery

T1614

System Language Discovery