remcos | d412692f582acd9abf0771e44b9a6915956b4633777078d3d488be6db7802203

Modify Registry

description	ioc	Process
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\Userinit = "C:\\WINDOWS\\system32\\userinit.exe, \"C:\\Windows\\SysWOW64\\InstallCalc\\InstallCalc.exe\""	JaffaCakes118_d412692f582acd9abf0771e44b9a6915956b4633777078d3d488be6db7802203.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\Userinit = "C:\\WINDOWS\\system32\\userinit.exe, \"C:\\Windows\\SysWOW64\\InstallCalc\\InstallCalc.exe\""	InstallCalc.exe

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

Checks computer location settings 2 TTPs 2 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-1-5-21-4089630652-1596403869-279772308-1000\Control Panel\International\Geo\Nation	JaffaCakes118_d412692f582acd9abf0771e44b9a6915956b4633777078d3d488be6db7802203.exe
Key value queried	\REGISTRY\USER\S-1-5-21-4089630652-1596403869-279772308-1000\Control Panel\International\Geo\Nation	WScript.exe

Deletes itself 1 IoCs

pid	Process
4212	WScript.exe

Executes dropped EXE 1 IoCs

pid	Process
3652	InstallCalc.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-1-5-21-4089630652-1596403869-279772308-1000\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\InstallCalc = "\"C:\\Windows\\SysWOW64\\InstallCalc\\InstallCalc.exe\""	JaffaCakes118_d412692f582acd9abf0771e44b9a6915956b4633777078d3d488be6db7802203.exe
Set value (str)	\REGISTRY\USER\S-1-5-21-4089630652-1596403869-279772308-1000\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\InstallCalc = "\"C:\\Windows\\SysWOW64\\InstallCalc\\InstallCalc.exe\""	InstallCalc.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\	InstallCalc.exe
Key created	\REGISTRY\MACHINE\Software\WOW6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\	JaffaCakes118_d412692f582acd9abf0771e44b9a6915956b4633777078d3d488be6db7802203.exe

Drops file in System32 directory 4 IoCs

description	ioc	Process
File opened for modification	C:\Windows\SysWOW64\InstallCalc\InstallCalc.exe	JaffaCakes118_d412692f582acd9abf0771e44b9a6915956b4633777078d3d488be6db7802203.exe
File opened for modification	C:\Windows\SysWOW64\InstallCalc\logs.dat	InstallCalc.exe
File created	C:\Windows\SysWOW64\InstallCalc\logs.dat	InstallCalc.exe
File created	C:\Windows\SysWOW64\InstallCalc\InstallCalc.exe	JaffaCakes118_d412692f582acd9abf0771e44b9a6915956b4633777078d3d488be6db7802203.exe

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 4 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	JaffaCakes118_d412692f582acd9abf0771e44b9a6915956b4633777078d3d488be6db7802203.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	WScript.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cmd.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	InstallCalc.exe

Modifies registry class 1 IoCs

description	ioc	Process
Key created	\REGISTRY\USER\S-1-5-21-4089630652-1596403869-279772308-1000_Classes\Local Settings	JaffaCakes118_d412692f582acd9abf0771e44b9a6915956b4633777078d3d488be6db7802203.exe

Suspicious use of SetWindowsHookEx 1 IoCs

pid	Process
3652	InstallCalc.exe

Suspicious use of WriteProcessMemory 9 IoCs

description	pid	Process	procid_target
PID 4760 wrote to memory of 4212	4760	JaffaCakes118_d412692f582acd9abf0771e44b9a6915956b4633777078d3d488be6db7802203.exe	82
PID 4760 wrote to memory of 4212	4760	JaffaCakes118_d412692f582acd9abf0771e44b9a6915956b4633777078d3d488be6db7802203.exe	82
PID 4760 wrote to memory of 4212	4760	JaffaCakes118_d412692f582acd9abf0771e44b9a6915956b4633777078d3d488be6db7802203.exe	82
PID 4212 wrote to memory of 2544	4212	WScript.exe	83
PID 4212 wrote to memory of 2544	4212	WScript.exe	83
PID 4212 wrote to memory of 2544	4212	WScript.exe	83
PID 2544 wrote to memory of 3652	2544	cmd.exe	85
PID 2544 wrote to memory of 3652	2544	cmd.exe	85
PID 2544 wrote to memory of 3652	2544	cmd.exe	85

C:\Users\Admin\AppData\Local\Temp\JaffaCakes118_d412692f582acd9abf0771e44b9a6915956b4633777078d3d488be6db7802203.exe
"C:\Users\Admin\AppData\Local\Temp\JaffaCakes118_d412692f582acd9abf0771e44b9a6915956b4633777078d3d488be6db7802203.exe"
1⤵
- Modifies WinLogon for persistence
- Checks computer location settings
- Adds Run key to start application
- Modifies WinLogon
- Drops file in System32 directory
- System Location Discovery: System Language Discovery
- Modifies registry class
- Suspicious use of WriteProcessMemory
PID:4760
- C:\Windows\SysWOW64\WScript.exe
  "C:\Windows\System32\WScript.exe" "C:\Users\Admin\AppData\Local\Temp\install.vbs"
  2⤵
  - Checks computer location settings
  - Deletes itself
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:4212
- - C:\Windows\SysWOW64\cmd.exe
    "C:\Windows\System32\cmd.exe" /c "C:\Windows\SysWOW64\InstallCalc\InstallCalc.exe"
    3⤵
    - System Location Discovery: System Language Discovery
    - Suspicious use of WriteProcessMemory
    PID:2544
  - - C:\Windows\SysWOW64\InstallCalc\InstallCalc.exe
      C:\Windows\SysWOW64\InstallCalc\InstallCalc.exe
      4⤵
      Modifies WinLogon for persistence
      Executes dropped EXE
      Adds Run key to start application
      Modifies WinLogon
      Drops file in System32 directory
      System Location Discovery: System Language Discovery
      Suspicious use of SetWindowsHookEx
      PID:3652

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Persistence

Boot or Logon Autostart Execution

3

T1547

Registry Run Keys / Startup Folder

T1547.001

Winlogon Helper DLL

2

Privilege Escalation

Boot or Logon Autostart Execution

3

T1547

Registry Run Keys / Startup Folder

T1547.001

Winlogon Helper DLL

2

Defense Evasion

Modify Registry

3

Credential Access

Discovery

Query Registry

T1012

System Information Discovery

2

T1082

System Location Discovery

T1614

System Language Discovery