remcos | 6182c4acf47f39e0ab54ba35cb5e69c8bdbd2ee76a64939c94c26b6bdcbc65bb

General

Target

remcos_a.exe
Size

469KB
MD5

43639322671579f8a99a8a42e42777cf
SHA1

0e397ebf8a3c5ab8c84424c674daa74674710519
SHA256

6182c4acf47f39e0ab54ba35cb5e69c8bdbd2ee76a64939c94c26b6bdcbc65bb
SHA512

cd26a73fa99a4e0ec2e353058fc95a02f6e12243aefc0cee07bcff99f6b89fef3c81c90e0fbb7dedd58dd9d114c480f83ed5559edce581b2db9cf72dcc528d72
SSDEEP

12288:Wmnk7iLJbpIpiRL6I2WhSKQ9ZsfZQSIn9:uiLJbpI7I2WhQqZ7I9

Score

10^/10

remcos remotehost discovery persistence rat

Malware Config

Extracted

Family

remcos

Botnet

RemoteHost

C2

195.88.218.126:2404

Attributes

audio_folder
MicRecords
audio_record_time
5
connect_delay
0
connect_interval
1
copy_file
remcos.exe
copy_folder
1034
delete_file
false
hide_file
false
hide_keylog_file
false
install_flag
true
install_path
%WinDir%\System32
keylog_crypt
true
keylog_file
logs.dat
keylog_flag
false
keylog_folder
macrosoft
keylog_path
%AppData%
mouse_option
false
mutex
Rmc-I0SVLJ
screenshot_crypt
false
screenshot_flag
false
screenshot_folder
Screenshots
screenshot_path
%AppData%
screenshot_time
10
startup_value
sihost
take_screenshot_option
false
take_screenshot_time
5

Signatures

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

Adds policy Run key to start application 2 TTPs 4 IoCs

persistence

Registry Run Keys / Startup Folder

T1547.001

Modify Registry

T1112

description	ioc	Process
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\Run\sihost = "\"C:\\Windows\\SysWOW64\\1034\\remcos.exe\""	remcos.exe
Key created	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\Run	remcos_a.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\Run\sihost = "\"C:\\Windows\\SysWOW64\\1034\\remcos.exe\""	remcos_a.exe
Key created	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\Run	remcos.exe

Executes dropped EXE 1 IoCs

pid	Process
3728	remcos.exe

Adds Run key to start application 2 TTPs 4 IoCs

persistence

Registry Run Keys / Startup Folder

T1547.001

Modify Registry

T1112

description	ioc	Process
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Run\sihost = "\"C:\\Windows\\SysWOW64\\1034\\remcos.exe\""	remcos.exe
Set value (str)	\REGISTRY\USER\S-1-5-21-1298619118-249045975-4264763259-1000\Software\Microsoft\Windows\CurrentVersion\Run\sihost = "\"C:\\Windows\\SysWOW64\\1034\\remcos.exe\""	remcos_a.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Run\sihost = "\"C:\\Windows\\SysWOW64\\1034\\remcos.exe\""	remcos_a.exe
Set value (str)	\REGISTRY\USER\S-1-5-21-1298619118-249045975-4264763259-1000\Software\Microsoft\Windows\CurrentVersion\Run\sihost = "\"C:\\Windows\\SysWOW64\\1034\\remcos.exe\""	remcos.exe

Drops file in System32 directory 2 IoCs

description	ioc	Process
File created	C:\Windows\SysWOW64\1034\remcos.exe	remcos_a.exe
File opened for modification	C:\Windows\SysWOW64\1034\remcos.exe	remcos_a.exe

Suspicious use of SetThreadContext 1 IoCs

description	pid	Process	procid_target
PID 3728 set thread context of 4772	3728	remcos.exe	86

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	remcos_a.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	remcos.exe

Modifies registry class 1 IoCs

description	ioc	Process
Key created	\REGISTRY\USER\S-1-5-21-1298619118-249045975-4264763259-1000_Classes\Local Settings	remcos_a.exe

Suspicious behavior: EnumeratesProcesses 2 IoCs

pid	Process
3728	remcos.exe
3728	remcos.exe

Suspicious behavior: MapViewOfSection 1 IoCs

pid	Process
3728	remcos.exe

Suspicious use of WriteProcessMemory 13 IoCs

description	pid	Process	procid_target
PID 3892 wrote to memory of 4236	3892	remcos_a.exe	81
PID 3892 wrote to memory of 4236	3892	remcos_a.exe	81
PID 3892 wrote to memory of 4236	3892	remcos_a.exe	81
PID 4236 wrote to memory of 4872	4236	WScript.exe	83
PID 4236 wrote to memory of 4872	4236	WScript.exe	83
PID 4236 wrote to memory of 4872	4236	WScript.exe	83
PID 4872 wrote to memory of 3728	4872	cmd.exe	85
PID 4872 wrote to memory of 3728	4872	cmd.exe	85
PID 4872 wrote to memory of 3728	4872	cmd.exe	85
PID 3728 wrote to memory of 4772	3728	remcos.exe	86
PID 3728 wrote to memory of 4772	3728	remcos.exe	86
PID 3728 wrote to memory of 4772	3728	remcos.exe	86
PID 3728 wrote to memory of 4772	3728	remcos.exe	86

C:\Users\Admin\AppData\Local\Temp\remcos_a.exe
"C:\Users\Admin\AppData\Local\Temp\remcos_a.exe"
1⤵
- Adds policy Run key to start application
- Adds Run key to start application
- Drops file in System32 directory
- System Location Discovery: System Language Discovery
- Modifies registry class
- Suspicious use of WriteProcessMemory
PID:3892
- C:\Windows\SysWOW64\WScript.exe
  "C:\Windows\System32\WScript.exe" "C:\Users\Admin\AppData\Local\Temp\install.vbs"
  2⤵
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:4236
- - C:\Windows\SysWOW64\cmd.exe
    "C:\Windows\System32\cmd.exe" /c "C:\Windows\SysWOW64\1034\remcos.exe"
    3⤵
    - System Location Discovery: System Language Discovery
    - Suspicious use of WriteProcessMemory
    PID:4872
  - - C:\Windows\SysWOW64\1034\remcos.exe
      C:\Windows\SysWOW64\1034\remcos.exe
      4⤵
      Adds policy Run key to start application
      Executes dropped EXE
      Adds Run key to start application
      Suspicious use of SetThreadContext
      System Location Discovery: System Language Discovery
      Suspicious behavior: EnumeratesProcesses
      Suspicious behavior: MapViewOfSection
      Suspicious use of WriteProcessMemory
      PID:3728
    - - \??\c:\program files (x86)\internet explorer\iexplore.exe
        
        "c:\program files (x86)\internet explorer\iexplore.exe"
        5⤵
        
        PID:4772

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Persistence

Boot or Logon Autostart Execution

2

T1547

Registry Run Keys / Startup Folder

2

T1547.001

Privilege Escalation

Boot or Logon Autostart Execution

2

T1547

Registry Run Keys / Startup Folder

2

T1547.001

Defense Evasion

Modify Registry

2

T1112

Credential Access

Discovery

System Information Discovery

1

T1082

System Location Discovery

1

T1614

System Language Discovery

1

T1614.001

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

C:\Users\Admin\AppData\Local\Temp\install.vbs

Filesize
392B

MD5
2d8a449cb6f9305edf06d1d41096a959

SHA1
7b707ed7559d491dd224f85c72453839ea17578d

SHA256
4209f29e5ee910794e83f75ad5880f00af4b11225f978944170a225dd88bbca7

SHA512
de60b300a990d836b47c5f8c83c29326ff513d74cf9b055a88a208dcd44095bef04f493f013fa202c4c4f650b215fbe7312c9d2d7fee50274711c80277dd16b8

Download Submit
C:\Windows\SysWOW64\1034\remcos.exe

Filesize
469KB

MD5
43639322671579f8a99a8a42e42777cf

SHA1
0e397ebf8a3c5ab8c84424c674daa74674710519

SHA256
6182c4acf47f39e0ab54ba35cb5e69c8bdbd2ee76a64939c94c26b6bdcbc65bb

SHA512
cd26a73fa99a4e0ec2e353058fc95a02f6e12243aefc0cee07bcff99f6b89fef3c81c90e0fbb7dedd58dd9d114c480f83ed5559edce581b2db9cf72dcc528d72

Download Submit
memory/4772-8-0x0000000001000000-0x000000000107F000-memory.dmp

Filesize
508KB

Download
memory/4772-10-0x0000000001000000-0x000000000107F000-memory.dmp

Filesize
508KB

Download
memory/4772-9-0x0000000001000000-0x000000000107F000-memory.dmp

Filesize
508KB

Download
memory/4772-11-0x0000000001000000-0x000000000107F000-memory.dmp

Filesize
508KB

Download

Analysis

Sharing

General

Malware Config

Extracted

Signatures

Processes

Network

MITRE ATT&CK Enterprise v15

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Downloads