Analysis

  • max time kernel
    91s
  • max time network
    149s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20220812-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20220812-enlocale:en-usos:windows10-2004-x64system
  • submitted
    20-02-2023 10:01

General

  • Target

    tmp.exe

  • Size

    36KB

  • MD5

    148264565031a8ebb6887a1395a2247a

  • SHA1

    3e4238c2f8e69b5c692ef034b6ed6d4ec7673919

  • SHA256

    683fa1e449da9b71d0cafefb107efd97f0f8163f844dd837d12c354c2b901b93

  • SHA512

    41c84fbbfecabcae861eb10216b3910d0f5ddf7e62258e164558485bc6fae2df664cf489f8fab672eb752217c9b052e12fb2e9a1bea68530f25512e8f5f690f9

  • SSDEEP

    768:U5PHyCjmhFdWfLubuZ1kvIaEekM2Q0KbzssZr1:U5PHfjGPAKbLV2o3r

Malware Config

Extracted

Family

remcos

Version

1.7 Pro

Botnet

1877

C2

hawler.duckdns.org:2404

5.206.227.115:2404

Attributes
  • audio_folder

    audio

  • audio_path

    %AppData%

  • audio_record_time

    5

  • connect_delay

    0

  • connect_interval

    5

  • copy_file

    svshost.exe

  • copy_folder

    1877

  • delete_file

    false

  • hide_file

    true

  • hide_keylog_file

    false

  • install_flag

    true

  • install_path

    %WinDir%

  • keylog_crypt

    false

  • keylog_file

    logs.dat

  • keylog_flag

    false

  • keylog_folder

    1877

  • keylog_path

    %AppData%

  • mouse_option

    true

  • mutex

    1877_spelzoyulk

  • screenshot_crypt

    false

  • screenshot_flag

    false

  • screenshot_folder

    Screens

  • screenshot_path

    %AppData%

  • screenshot_time

    1

  • startup_value

    Google Update

  • take_screenshot_option

    false

  • take_screenshot_time

    5

Signatures

  • Modifies WinLogon for persistence 2 TTPs 4 IoCs
  • Remcos

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

  • Identifies VirtualBox via ACPI registry values (likely anti-VM) 2 TTPs 2 IoCs
  • Adds policy Run key to start application 2 TTPs 4 IoCs
  • Checks computer location settings 2 TTPs 1 IoCs

    Looks up country code configured in the registry, likely geofence.

  • Executes dropped EXE 1 IoCs
  • UPX packed file 6 IoCs

    Detects executables packed with UPX/modified UPX open source packer.

  • Adds Run key to start application 2 TTPs 8 IoCs
  • Modifies WinLogon 2 TTPs 2 IoCs
  • Drops file in Windows directory 3 IoCs
  • Enumerates physical storage devices 1 TTPs

    Attempts to interact with connected storage/optical drive(s). Likely ransomware behaviour.

  • Runs ping.exe 1 TTPs 1 IoCs
  • Suspicious use of SetWindowsHookEx 1 IoCs
  • Suspicious use of WriteProcessMemory 9 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\tmp.exe
    "C:\Users\Admin\AppData\Local\Temp\tmp.exe"
    1⤵
    • Modifies WinLogon for persistence
    • Identifies VirtualBox via ACPI registry values (likely anti-VM)
    • Adds policy Run key to start application
    • Checks computer location settings
    • Adds Run key to start application
    • Modifies WinLogon
    • Drops file in Windows directory
    • Suspicious use of WriteProcessMemory
    PID:944
    • C:\Windows\SysWOW64\cmd.exe
      C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Local\Temp\install.bat" "
      2⤵
      • Suspicious use of WriteProcessMemory
      PID:3948
      • C:\Windows\SysWOW64\PING.EXE
        PING 127.0.0.1 -n 2
        3⤵
        • Runs ping.exe
        PID:4912
      • C:\Windows\1877\svshost.exe
        "C:\Windows\1877\svshost.exe"
        3⤵
        • Modifies WinLogon for persistence
        • Identifies VirtualBox via ACPI registry values (likely anti-VM)
        • Adds policy Run key to start application
        • Executes dropped EXE
        • Adds Run key to start application
        • Modifies WinLogon
        • Suspicious use of SetWindowsHookEx
        PID:4888

Network

MITRE ATT&CK Matrix ATT&CK v6

Persistence

Winlogon Helper DLL

2
T1004

Registry Run Keys / Startup Folder

2
T1060

Defense Evasion

Modify Registry

4
T1112

Virtualization/Sandbox Evasion

1
T1497

Discovery

Query Registry

2
T1012

Virtualization/Sandbox Evasion

1
T1497

System Information Discovery

2
T1082

Remote System Discovery

1
T1018

Replay Monitor

Loading Replay Monitor...

Downloads

  • C:\Users\Admin\AppData\Local\Temp\install.bat
    Filesize

    78B

    MD5

    f35509e5938343750502f45e998f8d0c

    SHA1

    74efa4a149f83d677bdf347149d33e0c25cb5af0

    SHA256

    969621479c4bc68f58f32db1d20a5f389200fee6cdf30e73fe70072184f58afb

    SHA512

    abb32f92b0dc6d76a5dd83a4d9268e321092626a5b810cbb9c96347e1b40d98ccada231b8d6ad5d5252a2e24082c88f184b201c399106248ea3de564b3483091

  • C:\Windows\1877\svshost.exe
    Filesize

    36KB

    MD5

    148264565031a8ebb6887a1395a2247a

    SHA1

    3e4238c2f8e69b5c692ef034b6ed6d4ec7673919

    SHA256

    683fa1e449da9b71d0cafefb107efd97f0f8163f844dd837d12c354c2b901b93

    SHA512

    41c84fbbfecabcae861eb10216b3910d0f5ddf7e62258e164558485bc6fae2df664cf489f8fab672eb752217c9b052e12fb2e9a1bea68530f25512e8f5f690f9

  • C:\Windows\1877\svshost.exe
    Filesize

    36KB

    MD5

    148264565031a8ebb6887a1395a2247a

    SHA1

    3e4238c2f8e69b5c692ef034b6ed6d4ec7673919

    SHA256

    683fa1e449da9b71d0cafefb107efd97f0f8163f844dd837d12c354c2b901b93

    SHA512

    41c84fbbfecabcae861eb10216b3910d0f5ddf7e62258e164558485bc6fae2df664cf489f8fab672eb752217c9b052e12fb2e9a1bea68530f25512e8f5f690f9

  • memory/944-132-0x0000000000400000-0x000000000041D000-memory.dmp
    Filesize

    116KB

  • memory/944-134-0x0000000000400000-0x000000000041D000-memory.dmp
    Filesize

    116KB

  • memory/3948-133-0x0000000000000000-mapping.dmp
  • memory/4888-137-0x0000000000000000-mapping.dmp
  • memory/4888-140-0x0000000000400000-0x000000000041D000-memory.dmp
    Filesize

    116KB

  • memory/4888-141-0x0000000000400000-0x000000000041D000-memory.dmp
    Filesize

    116KB

  • memory/4912-136-0x0000000000000000-mapping.dmp