Analysis

  • max time kernel
    150s
  • max time network
    181s
  • platform
    windows7_x64
  • resource
    win7-20220414-en
  • submitted
    20-05-2022 22:16

General

  • Target

    PO839-DOC83475348-834_pdf.exe

  • Size

    169KB

  • MD5

    f0a88db6d16630640775a733efd9527f

  • SHA1

    88fc7c4275f93c404efa073a80ce61e0e7f3ee5a

  • SHA256

    ff3eb81477b36ac2239b623085961439379064929b20c4a69f72cb266adece83

  • SHA512

    af00550e84d345289e6d1751f42be955a3d60a2e5a4f442764dfbb044b7e0c8d775e8af89c0d217bd8023d4a4739b77600ba9365f47cde5086afead6180f6ddf

Malware Config

Extracted

Family

remcos

Version

2.5.1 Pro

Botnet

xxxxxxxxxxxx

C2

109.169.89.116:2021

Attributes
  • audio_folder

    MicRecords

  • audio_path

    %AppData%

  • 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

  • install_path

    %AppData%

  • keylog_crypt

    false

  • keylog_file

    s.sex

  • keylog_flag

    false

  • keylog_folder

    ssssss

  • keylog_path

    %UserProfile%

  • mouse_option

    false

  • mutex

    fuckhere-M9W1LK

  • screenshot_crypt

    false

  • screenshot_flag

    false

  • screenshot_folder

    Screenshots

  • screenshot_path

    %AppData%

  • screenshot_time

    10

  • startup_value

    remcos

  • take_screenshot_option

    false

  • take_screenshot_time

    5

  • take_screenshot_title

    wikipedia;solitaire;

Signatures

  • Remcos

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

  • Looks for VirtualBox Guest Additions in registry 2 TTPs
  • Looks for VMWare Tools registry key 2 TTPs
  • Checks BIOS information in registry 2 TTPs 2 IoCs

    BIOS information is often read in order to detect sandboxing environments.

  • Maps connected drives based on registry 3 TTPs 2 IoCs

    Disk information is often read in order to detect sandboxing environments.

  • Suspicious use of SetThreadContext 1 IoCs
  • Enumerates physical storage devices 1 TTPs

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

  • Creates scheduled task(s) 1 TTPs 1 IoCs

    Schtasks is often used by malware for persistence or to perform post-infection execution.

  • Suspicious behavior: EnumeratesProcesses 1 IoCs
  • Suspicious use of AdjustPrivilegeToken 1 IoCs
  • Suspicious use of SetWindowsHookEx 1 IoCs
  • Suspicious use of WriteProcessMemory 15 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\PO839-DOC83475348-834_pdf.exe
    "C:\Users\Admin\AppData\Local\Temp\PO839-DOC83475348-834_pdf.exe"
    1⤵
    • Checks BIOS information in registry
    • Maps connected drives based on registry
    • Suspicious use of SetThreadContext
    • Suspicious behavior: EnumeratesProcesses
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    PID:1656
    • C:\Windows\SysWOW64\schtasks.exe
      "C:\Windows\System32\schtasks.exe" /Create /TN "Updates\stsVISqZItxBpu" /XML "C:\Users\Admin\AppData\Local\Temp\tmp1E3B.tmp"
      2⤵
      • Creates scheduled task(s)
      PID:1164
    • C:\Users\Admin\AppData\Local\Temp\PO839-DOC83475348-834_pdf.exe
      "{path}"
      2⤵
      • Suspicious use of SetWindowsHookEx
      PID:1364

Network

MITRE ATT&CK Matrix ATT&CK v6

Execution

Scheduled Task

1
T1053

Persistence

Scheduled Task

1
T1053

Privilege Escalation

Scheduled Task

1
T1053

Defense Evasion

Virtualization/Sandbox Evasion

2
T1497

Discovery

Query Registry

4
T1012

Virtualization/Sandbox Evasion

2
T1497

System Information Discovery

3
T1082

Peripheral Device Discovery

1
T1120

Replay Monitor

Loading Replay Monitor...

Downloads

  • C:\Users\Admin\AppData\Local\Temp\tmp1E3B.tmp
    Filesize

    1KB

    MD5

    df1010249d384ba4f3177efa9a45c4ee

    SHA1

    348e5586b0e68c0135cd2b2b5a5a9e0e29d5703e

    SHA256

    d7049beb9a6f3759f100ac58a39adfdc3643a9500831c4d46d00a47fb2cb55d4

    SHA512

    2741399d21d691dd4cfd9e32c721edf25b22ee586842155a0f690da1954b350dafbf9fdb5aacd70e12381e438afd9ba0f47f66c44abcdf246ddd6d18861710ba

  • memory/1164-58-0x0000000000000000-mapping.dmp
  • memory/1364-65-0x0000000000400000-0x0000000000420000-memory.dmp
    Filesize

    128KB

  • memory/1364-66-0x0000000000400000-0x0000000000420000-memory.dmp
    Filesize

    128KB

  • memory/1364-74-0x0000000000400000-0x0000000000420000-memory.dmp
    Filesize

    128KB

  • memory/1364-73-0x0000000000400000-0x0000000000420000-memory.dmp
    Filesize

    128KB

  • memory/1364-61-0x0000000000400000-0x0000000000420000-memory.dmp
    Filesize

    128KB

  • memory/1364-60-0x0000000000400000-0x0000000000420000-memory.dmp
    Filesize

    128KB

  • memory/1364-70-0x0000000000413B74-mapping.dmp
  • memory/1364-69-0x0000000000400000-0x0000000000420000-memory.dmp
    Filesize

    128KB

  • memory/1364-63-0x0000000000400000-0x0000000000420000-memory.dmp
    Filesize

    128KB

  • memory/1364-67-0x0000000000400000-0x0000000000420000-memory.dmp
    Filesize

    128KB

  • memory/1656-57-0x00000000041B0000-0x00000000041DE000-memory.dmp
    Filesize

    184KB

  • memory/1656-54-0x0000000000360000-0x0000000000390000-memory.dmp
    Filesize

    192KB

  • memory/1656-55-0x0000000075781000-0x0000000075783000-memory.dmp
    Filesize

    8KB

  • memory/1656-56-0x00000000003B0000-0x00000000003B8000-memory.dmp
    Filesize

    32KB