Analysis

  • max time kernel
    99s
  • max time network
    155s
  • platform
    windows10-ltsc 2021_x64
  • resource
    win10ltsc2021-20241023-en
  • resource tags

    arch:x64arch:x86image:win10ltsc2021-20241023-enlocale:en-usos:windows10-ltsc 2021-x64system
  • submitted
    03-11-2024 19:51

General

  • Target

    Client-built.exe

  • Size

    3.1MB

  • MD5

    f5b93af3ee1b64dacd2bac9ba4af9b27

  • SHA1

    1f2a038199a71a2b917dca4dff2f5fac5e840978

  • SHA256

    48d4fde21b28f0614fdf124f83f5594bddc13292f21b775da58b017385a49b01

  • SHA512

    83703b0f567723abe3d6b34bd419be5df3475e049ae8893993fec017da9a420cd875184c570bdffbfc0bccac662762991885dea8ebcc2af172b3aac2fb00a302

  • SSDEEP

    49152:mv2I22SsaNYfdPBldt698dBcjHQzRJ6TbR3LoGd/oobTHHB72eh2NT:mvb22SsaNYfdPBldt6+dBcjHQzRJ6FA

Malware Config

Extracted

Family

quasar

Version

1.4.1

Botnet

Office04

C2

Inversin-43597.portmap.host:43597

Mutex

80329fd2-f063-4b06-9c7e-8dbc6278c2a3

Attributes
  • encryption_key

    744EA1A385FEBC6DA96387411B7000D77E66B075

  • install_name

    Client.exe

  • log_directory

    Logs

  • reconnect_delay

    3000

  • startup_key

    java updater

  • subdirectory

    SubDir

Signatures

  • Quasar RAT

    Quasar is an open source Remote Access Tool.

  • Quasar family
  • Quasar payload 2 IoCs
  • Executes dropped EXE 1 IoCs
  • Enumerates physical storage devices 1 TTPs

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

  • Scheduled Task/Job: Scheduled Task 1 TTPs 2 IoCs

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

  • Suspicious use of AdjustPrivilegeToken 2 IoCs
  • Suspicious use of FindShellTrayWindow 3 IoCs
  • Suspicious use of SendNotifyMessage 3 IoCs
  • Suspicious use of WriteProcessMemory 6 IoCs
  • Uses Task Scheduler COM API 1 TTPs

    The Task Scheduler COM API can be used to schedule applications to run on boot or at set times.

Processes

  • C:\Users\Admin\AppData\Local\Temp\Client-built.exe
    "C:\Users\Admin\AppData\Local\Temp\Client-built.exe"
    1⤵
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    PID:4036
    • C:\Windows\SYSTEM32\schtasks.exe
      "schtasks" /create /tn "java updater" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\SubDir\Client.exe" /rl HIGHEST /f
      2⤵
      • Scheduled Task/Job: Scheduled Task
      PID:5068
    • C:\Users\Admin\AppData\Roaming\SubDir\Client.exe
      "C:\Users\Admin\AppData\Roaming\SubDir\Client.exe"
      2⤵
      • Executes dropped EXE
      • Suspicious use of AdjustPrivilegeToken
      • Suspicious use of FindShellTrayWindow
      • Suspicious use of SendNotifyMessage
      • Suspicious use of WriteProcessMemory
      PID:4088
      • C:\Windows\SYSTEM32\schtasks.exe
        "schtasks" /create /tn "java updater" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\SubDir\Client.exe" /rl HIGHEST /f
        3⤵
        • Scheduled Task/Job: Scheduled Task
        PID:544

Network

MITRE ATT&CK Enterprise v15

Replay Monitor

Loading Replay Monitor...

Downloads

  • C:\Users\Admin\AppData\Roaming\SubDir\Client.exe

    Filesize

    3.1MB

    MD5

    f5b93af3ee1b64dacd2bac9ba4af9b27

    SHA1

    1f2a038199a71a2b917dca4dff2f5fac5e840978

    SHA256

    48d4fde21b28f0614fdf124f83f5594bddc13292f21b775da58b017385a49b01

    SHA512

    83703b0f567723abe3d6b34bd419be5df3475e049ae8893993fec017da9a420cd875184c570bdffbfc0bccac662762991885dea8ebcc2af172b3aac2fb00a302

  • memory/4036-0-0x00007FF8C1303000-0x00007FF8C1305000-memory.dmp

    Filesize

    8KB

  • memory/4036-1-0x0000000000370000-0x0000000000694000-memory.dmp

    Filesize

    3.1MB

  • memory/4036-2-0x00007FF8C1300000-0x00007FF8C1DC2000-memory.dmp

    Filesize

    10.8MB

  • memory/4036-5-0x00007FF8C1300000-0x00007FF8C1DC2000-memory.dmp

    Filesize

    10.8MB

  • memory/4088-6-0x00007FF8C1300000-0x00007FF8C1DC2000-memory.dmp

    Filesize

    10.8MB

  • memory/4088-7-0x00007FF8C1300000-0x00007FF8C1DC2000-memory.dmp

    Filesize

    10.8MB

  • memory/4088-8-0x000000001C6B0000-0x000000001C700000-memory.dmp

    Filesize

    320KB

  • memory/4088-9-0x000000001C7C0000-0x000000001C872000-memory.dmp

    Filesize

    712KB

  • memory/4088-12-0x000000001C700000-0x000000001C712000-memory.dmp

    Filesize

    72KB

  • memory/4088-13-0x000000001C760000-0x000000001C79C000-memory.dmp

    Filesize

    240KB

  • memory/4088-14-0x00007FF8C1300000-0x00007FF8C1DC2000-memory.dmp

    Filesize

    10.8MB