remcos | 553bd8b6c13d775bbaa9c5b2d9c02ee8df0e232180dfd17c5f7a67188bb3e218

General

Target

TaxDocuments.exe
Size

1.7MB
MD5

30307b319b2451b6bf61d3e6b232f1da
SHA1

6a512848872be1325761e7ca110e0a1ee91cb0ef
SHA256

a7dbbad8a1cd038e5ab5b3c6b1b312774d808e4b0a2254e8039036972ac8881a
SHA512

7833ecb30a75324af6852e3583a609a653652f3cda9037ace7a1098ce7e52ed4b994c5ff1a0a0b4db748a01b06e8d4b8a10a50ebb9c0d4fbc8aa12dd1168f0b7
SSDEEP

24576:17AMY27PG+4VWz3zYxQ2IQKbvavAyoVVxPuOcabAC9fH6lJUkwJYaTTgKmfa8+:Nwj+4VWnoqSkHNckbfH6lJ2XgKmf+

Score

10^/10

remcos remotehost discovery persistence rat

Malware Config

Extracted

Family

remcos

Botnet

RemoteHost

C2

privmerkt.com:6042

Attributes

audio_folder
MicRecords
audio_record_time
5
connect_delay
0
connect_interval
1
copy_file
remcos.exe
copy_folder
Remcos
delete_file
false
hide_file
false
hide_keylog_file
false
install_flag
false
keylog_crypt
false
keylog_file
logs.dat
keylog_flag
false
keylog_folder
remcos
mouse_option
false
mutex
Rmc-BMG9AW
screenshot_crypt
false
screenshot_flag
false
screenshot_folder
Screenshots
screenshot_path
%AppData%
screenshot_time
10
take_screenshot_option
false
take_screenshot_time
5

Signatures

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

Adds Run key to start application 2 TTPs 1 IoCs

persistence

Registry Run Keys / Startup Folder

T1547.001

Modify Registry

T1112

description	ioc	Process
Set value (str)	\REGISTRY\USER\S-1-5-21-355097885-2402257403-2971294179-1000\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\*ChromeUpdate = "rundll32.exe C:\\Users\\Admin\\Documents\\FirefoxData.dll,EntryPoint"	reg.exe

Suspicious use of NtCreateThreadExHideFromDebugger 1 IoCs

pid	Process
2300	TaxDocuments.exe

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	TaxDocuments.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	TaxDocuments.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cmd.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	reg.exe

Suspicious use of WriteProcessMemory 12 IoCs

description	pid	Process	procid_target
PID 2300 wrote to memory of 4940	2300	TaxDocuments.exe	86
PID 2300 wrote to memory of 4940	2300	TaxDocuments.exe	86
PID 2300 wrote to memory of 4940	2300	TaxDocuments.exe	86
PID 2300 wrote to memory of 4940	2300	TaxDocuments.exe	86
PID 2300 wrote to memory of 4940	2300	TaxDocuments.exe	86
PID 2300 wrote to memory of 4940	2300	TaxDocuments.exe	86
PID 2300 wrote to memory of 4596	2300	TaxDocuments.exe	87
PID 2300 wrote to memory of 4596	2300	TaxDocuments.exe	87
PID 2300 wrote to memory of 4596	2300	TaxDocuments.exe	87
PID 4596 wrote to memory of 3700	4596	cmd.exe	89
PID 4596 wrote to memory of 3700	4596	cmd.exe	89
PID 4596 wrote to memory of 3700	4596	cmd.exe	89

C:\Users\Admin\AppData\Local\Temp\TaxDocuments.exe
"C:\Users\Admin\AppData\Local\Temp\TaxDocuments.exe"
1⤵
- Suspicious use of NtCreateThreadExHideFromDebugger
- System Location Discovery: System Language Discovery
- Suspicious use of WriteProcessMemory
PID:2300
- C:\Users\Admin\AppData\Local\Temp\TaxDocuments.exe
  "C:\Users\Admin\AppData\Local\Temp\TaxDocuments.exe"
  2⤵
  - System Location Discovery: System Language Discovery
  PID:4940
- C:\Windows\SysWOW64\cmd.exe
  cmd.exe /C reg add "HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Run" /v "*ChromeUpdate" /t REG_SZ /d "rundll32.exe C:\Users\Admin\Documents\FirefoxData.dll",EntryPoint /f & exit
  2⤵
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:4596
- - C:\Windows\SysWOW64\reg.exe
    reg add "HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Run" /v "*ChromeUpdate" /t REG_SZ /d "rundll32.exe C:\Users\Admin\Documents\FirefoxData.dll",EntryPoint /f
    3⤵
    - Adds Run key to start application
    - System Location Discovery: System Language Discovery
    PID:3700

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

System Location Discovery

1

T1614

System Language Discovery

1

T1614.001

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

memory/2300-0-0x0000000011000000-0x0000000011369000-memory.dmp

Filesize
3.4MB

Download
memory/2300-2-0x0000000010026000-0x0000000010040000-memory.dmp

Filesize
104KB

Download
memory/2300-1-0x0000000010000000-0x0000000010207000-memory.dmp

Filesize
2.0MB

Download
memory/2300-3-0x0000000010000000-0x0000000010207000-memory.dmp

Filesize
2.0MB

Download
memory/2300-8-0x0000000010000000-0x0000000010207000-memory.dmp

Filesize
2.0MB

Download
memory/2300-7-0x0000000010000000-0x0000000010207000-memory.dmp

Filesize
2.0MB

Download
memory/2300-19-0x0000000011000000-0x0000000011369000-memory.dmp

Filesize
3.4MB

Download
memory/4940-14-0x0000000000400000-0x0000000000482000-memory.dmp

Filesize
520KB

Download
memory/4940-20-0x0000000000400000-0x0000000000482000-memory.dmp

Filesize
520KB

Download
memory/4940-12-0x0000000000400000-0x0000000000482000-memory.dmp

Filesize
520KB

Download
memory/4940-10-0x0000000000400000-0x0000000000482000-memory.dmp

Filesize
520KB

Download
memory/4940-13-0x0000000000400000-0x0000000000482000-memory.dmp

Filesize
520KB

Download
memory/4940-9-0x0000000000400000-0x0000000000482000-memory.dmp

Filesize
520KB

Download
memory/4940-15-0x0000000000400000-0x0000000000482000-memory.dmp

Filesize
520KB

Download
memory/4940-16-0x0000000000400000-0x0000000000482000-memory.dmp

Filesize
520KB

Download
memory/4940-4-0x00000000001C0000-0x00000000001C1000-memory.dmp

Filesize
4KB

Download
memory/4940-11-0x0000000000400000-0x0000000000482000-memory.dmp

Filesize
520KB

Download
memory/4940-21-0x0000000000400000-0x0000000000482000-memory.dmp

Filesize
520KB

Download
memory/4940-22-0x0000000000400000-0x0000000000482000-memory.dmp

Filesize
520KB

Download
memory/4940-23-0x0000000000400000-0x0000000000482000-memory.dmp

Filesize
520KB

Download
memory/4940-24-0x0000000000400000-0x0000000000482000-memory.dmp

Filesize
520KB

Download
memory/4940-26-0x0000000000400000-0x0000000000482000-memory.dmp

Filesize
520KB

Download
memory/4940-25-0x0000000000400000-0x0000000000482000-memory.dmp

Filesize
520KB

Download
memory/4940-29-0x0000000000400000-0x0000000000482000-memory.dmp

Filesize
520KB

Download
memory/4940-30-0x0000000000400000-0x0000000000482000-memory.dmp

Filesize
520KB

Download

Analysis

Sharing

General

Malware Config

Extracted

Signatures

Processes

Network

MITRE ATT&CK Enterprise v15

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Downloads