remcos | 8741e2fc5b709526eaec1e791c56c7d2c65f312940b81e6027bd6ee2b181d940

General

Target

remcos_a.exe
Size

469KB
MD5

22ce3d0fc9f92829be87f978fc573680
SHA1

2a55144aed0886304b490fbcc623be46a8871065
SHA256

8741e2fc5b709526eaec1e791c56c7d2c65f312940b81e6027bd6ee2b181d940
SHA512

6bcd798e8db887dc0822ba196c2d9efb96fbe604f3728069d0bff04d5862c0d2ac2b4b2d810f310a2ec211e8244ce078b93d72debf427099dbce8f2420d88f4c
SSDEEP

12288:umnk7iLJbpIpiRL6I2WhSKQ9ZsfZQSEn9:WiLJbpI7I2WhQqZ7E9

Score

10^/10

remcos com surrogate discovery persistence rat

Malware Config

Extracted

Family

remcos

Botnet

COM Surrogate

C2

stay-daughters.gl.at.ply.gg:43206

Attributes

audio_folder
MicRecords
audio_record_time
5
connect_delay
0
connect_interval
1
copy_file
COM Surrogate.exe
copy_folder
COM Surrogate
delete_file
false
hide_file
false
hide_keylog_file
true
install_flag
true
keylog_crypt
true
keylog_file
logs.dat
keylog_flag
false
keylog_folder
Windows
mouse_option
false
mutex
Rmc-C5SENV
screenshot_crypt
false
screenshot_flag
false
screenshot_folder
Screenshots
screenshot_path
%AppData%
screenshot_time
10
startup_value
COM Surrogate
take_screenshot_option
false
take_screenshot_time
5

Signatures

Remcos
Remcos is a closed-source remote control and surveillance software.
rat 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-1-5-21-786284298-625481688-3210388970-1000\Control Panel\International\Geo\Nation	remcos_a.exe
Key value queried	\REGISTRY\USER\S-1-5-21-786284298-625481688-3210388970-1000\Control Panel\International\Geo\Nation	WScript.exe

Executes dropped EXE 1 IoCs

pid	Process
1716	COM Surrogate.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\USER\S-1-5-21-786284298-625481688-3210388970-1000\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\COM Surrogate = "\"C:\\ProgramData\\COM Surrogate\\COM Surrogate.exe\""	remcos_a.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Run\COM Surrogate = "\"C:\\ProgramData\\COM Surrogate\\COM Surrogate.exe\""	remcos_a.exe
Set value (str)	\REGISTRY\USER\S-1-5-21-786284298-625481688-3210388970-1000\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\COM Surrogate = "\"C:\\ProgramData\\COM Surrogate\\COM Surrogate.exe\""	COM Surrogate.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Run\COM Surrogate = "\"C:\\ProgramData\\COM Surrogate\\COM Surrogate.exe\""	COM Surrogate.exe

Suspicious use of SetThreadContext 1 IoCs

description	pid	Process	procid_target
PID 1716 set thread context of 3064	1716	COM Surrogate.exe	90

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	COM Surrogate.exe

Modifies registry class 1 IoCs

description	ioc	Process
Key created	\REGISTRY\USER\S-1-5-21-786284298-625481688-3210388970-1000_Classes\Local Settings	remcos_a.exe

Suspicious behavior: MapViewOfSection 1 IoCs

pid	Process
1716	COM Surrogate.exe

Suspicious use of WriteProcessMemory 13 IoCs

description	pid	Process	procid_target
PID 2696 wrote to memory of 1592	2696	remcos_a.exe	83
PID 2696 wrote to memory of 1592	2696	remcos_a.exe	83
PID 2696 wrote to memory of 1592	2696	remcos_a.exe	83
PID 1592 wrote to memory of 4948	1592	WScript.exe	87
PID 1592 wrote to memory of 4948	1592	WScript.exe	87
PID 1592 wrote to memory of 4948	1592	WScript.exe	87
PID 4948 wrote to memory of 1716	4948	cmd.exe	89
PID 4948 wrote to memory of 1716	4948	cmd.exe	89
PID 4948 wrote to memory of 1716	4948	cmd.exe	89
PID 1716 wrote to memory of 3064	1716	COM Surrogate.exe	90
PID 1716 wrote to memory of 3064	1716	COM Surrogate.exe	90
PID 1716 wrote to memory of 3064	1716	COM Surrogate.exe	90
PID 1716 wrote to memory of 3064	1716	COM Surrogate.exe	90

C:\Users\Admin\AppData\Local\Temp\remcos_a.exe
"C:\Users\Admin\AppData\Local\Temp\remcos_a.exe"
1⤵
- Checks computer location settings
- Adds Run key to start application
- System Location Discovery: System Language Discovery
- Modifies registry class
- Suspicious use of WriteProcessMemory
PID:2696
- C:\Windows\SysWOW64\WScript.exe
  "C:\Windows\System32\WScript.exe" "C:\Users\Admin\AppData\Local\Temp\install.vbs"
  2⤵
  - Checks computer location settings
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:1592
- - C:\Windows\SysWOW64\cmd.exe
    "C:\Windows\System32\cmd.exe" /c "C:\ProgramData\COM Surrogate\COM Surrogate.exe"
    3⤵
    - System Location Discovery: System Language Discovery
    - Suspicious use of WriteProcessMemory
    PID:4948
  - - C:\ProgramData\COM Surrogate\COM Surrogate.exe
      "C:\ProgramData\COM Surrogate\COM Surrogate.exe"
      4⤵
      Executes dropped EXE
      Adds Run key to start application
      Suspicious use of SetThreadContext
      System Location Discovery: System Language Discovery
      Suspicious behavior: MapViewOfSection
      Suspicious use of WriteProcessMemory
      PID:1716
    - - \??\c:\program files (x86)\internet explorer\iexplore.exe
        
        "c:\program files (x86)\internet explorer\iexplore.exe"
        5⤵
        
        PID:3064

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Persistence

Boot or Logon Autostart Execution

1

T1547

Registry Run Keys / Startup Folder

1

T1547.001

Privilege Escalation

Boot or Logon Autostart Execution

1

T1547

Registry Run Keys / Startup Folder

1

T1547.001

Defense Evasion

Modify Registry

1

T1112

Credential Access

Discovery

Query Registry

1

T1012

System Information Discovery

2

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:\ProgramData\COM Surrogate\COM Surrogate.exe

Filesize
469KB

MD5
22ce3d0fc9f92829be87f978fc573680

SHA1
2a55144aed0886304b490fbcc623be46a8871065

SHA256
8741e2fc5b709526eaec1e791c56c7d2c65f312940b81e6027bd6ee2b181d940

SHA512
6bcd798e8db887dc0822ba196c2d9efb96fbe604f3728069d0bff04d5862c0d2ac2b4b2d810f310a2ec211e8244ce078b93d72debf427099dbce8f2420d88f4c

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

Filesize
414B

MD5
01ea74daf9b956185c45016b68449bb0

SHA1
9d1a18d2c9a9f5ee04dc864adcd92f05577e9392

SHA256
1b22904a4106604da03fd63fad1663a3562f928fbe6bfc90af4b8239142e83da

SHA512
35566d72fc5739044bcb0ff14741c25aa0892fb6de57831eca737eb6896cd9c1c0837133504cf8df415a8e66196c317b86123967507d39814d3faaf989f8da02

Download Submit
memory/3064-8-0x0000000000140000-0x00000000001BF000-memory.dmp

Filesize
508KB

Download
memory/3064-10-0x0000000000140000-0x00000000001BF000-memory.dmp

Filesize
508KB

Download
memory/3064-9-0x0000000000140000-0x00000000001BF000-memory.dmp

Filesize
508KB

Download
memory/3064-11-0x0000000000140000-0x00000000001BF000-memory.dmp

Filesize
508KB

Download

Analysis

Sharing

General

Malware Config

Extracted

Signatures

Processes

Network

MITRE ATT&CK Enterprise v15

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Downloads