remcos | bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203c

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\""	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.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-1-5-21-3350944739-639801879-157714471-1000\Control Panel\International\Geo\Nation	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe
Key value queried	\REGISTRY\USER\S-1-5-21-3350944739-639801879-157714471-1000\Control Panel\International\Geo\Nation	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe
Key value queried	\REGISTRY\USER\S-1-5-21-3350944739-639801879-157714471-1000\Control Panel\International\Geo\Nation	Dxpserver.exe
Key value queried	\REGISTRY\USER\S-1-5-21-3350944739-639801879-157714471-1000\Control Panel\International\Geo\Nation	Dxpserver.exe

Executes dropped EXE 2 IoCs

pid	Process
436	Dxpserver.exe
1904	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-1-5-21-3350944739-639801879-157714471-1000\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\remcos = "\"C:\\Users\\Admin\\AppData\\Roaming\\remcos\\remcos.exe\""	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe
Set value (str)	\REGISTRY\USER\S-1-5-21-3350944739-639801879-157714471-1000\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\	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.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/0x000a000000023b82-15.dat	autoit_exe

Suspicious use of SetThreadContext 2 IoCs

description	pid	Process	procid_target
PID 2708 set thread context of 5040	2708	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe	83
PID 436 set thread context of 1904	436	Dxpserver.exe	105

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	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	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe

Modifies registry class 2 IoCs

description	ioc	Process
Key created	\REGISTRY\USER\S-1-5-21-3350944739-639801879-157714471-1000_Classes\Local Settings	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe
Key created	\REGISTRY\USER\S-1-5-21-3350944739-639801879-157714471-1000_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
2924	schtasks.exe
4908	schtasks.exe

Suspicious use of WriteProcessMemory 22 IoCs

description	pid	Process	procid_target
PID 2708 wrote to memory of 5040	2708	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe	83
PID 2708 wrote to memory of 5040	2708	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe	83
PID 2708 wrote to memory of 5040	2708	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe	83
PID 2708 wrote to memory of 5040	2708	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe	83
PID 2708 wrote to memory of 5040	2708	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe	83
PID 5040 wrote to memory of 2092	5040	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe	84
PID 5040 wrote to memory of 2092	5040	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe	84
PID 5040 wrote to memory of 2092	5040	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe	84
PID 2708 wrote to memory of 2924	2708	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe	95
PID 2708 wrote to memory of 2924	2708	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe	95
PID 2708 wrote to memory of 2924	2708	bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe	95
PID 436 wrote to memory of 1904	436	Dxpserver.exe	105
PID 436 wrote to memory of 1904	436	Dxpserver.exe	105
PID 436 wrote to memory of 1904	436	Dxpserver.exe	105
PID 436 wrote to memory of 1904	436	Dxpserver.exe	105
PID 436 wrote to memory of 1904	436	Dxpserver.exe	105
PID 1904 wrote to memory of 3148	1904	Dxpserver.exe	106
PID 1904 wrote to memory of 3148	1904	Dxpserver.exe	106
PID 1904 wrote to memory of 3148	1904	Dxpserver.exe	106
PID 436 wrote to memory of 4908	436	Dxpserver.exe	108
PID 436 wrote to memory of 4908	436	Dxpserver.exe	108
PID 436 wrote to memory of 4908	436	Dxpserver.exe	108

C:\Users\Admin\AppData\Local\Temp\bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe
"C:\Users\Admin\AppData\Local\Temp\bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe"
1⤵
- Checks computer location settings
- Suspicious use of SetThreadContext
- System Location Discovery: System Language Discovery
- Suspicious use of WriteProcessMemory
PID:2708
- C:\Users\Admin\AppData\Local\Temp\bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.exe
  "C:\Users\Admin\AppData\Local\Temp\bc45778b6b190ec52e270546b79c777086998534581316bfcb037ec1d523203cN.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:5040
- - 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:2092
- 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:2924

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:436
- 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:1904
- - 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:3148
- 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:4908

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