Analysis

  • max time kernel
    149s
  • max time network
    141s
  • platform
    windows10-ltsc_2021_x64
  • resource
    win10ltsc2021-20250314-en
  • resource tags

    arch:x64arch:x86image:win10ltsc2021-20250314-enlocale:en-usos:windows10-ltsc_2021-x64system
  • submitted
    20/04/2025, 12:58

General

  • Target

    Client-built.exe

  • Size

    3.1MB

  • MD5

    20e2ad97770afcb29a641ada5db33fe3

  • SHA1

    96931794912869c9f83e5e9a091bd290257f5b8b

  • SHA256

    3a3fd0e996477049a63b779dda5d31c20ebbae2b8733f3224ee7a2a88350175f

  • SHA512

    fc386626fef804a2aa221ebb3f420b7b5c2e63c359b5bdc915d9bc9ad72f8daea025329afd5e381f253635fdda681099a79f72283dbd6d22bfdde6bb519d6ac7

  • SSDEEP

    49152:+vht62XlaSFNWPjljiFa2RoUYIYFRJ6bbR3LoGdOcTHHB72eh2NT:+vL62XlaSFNWPjljiFXRoUYIYFRJ6te

Malware Config

Extracted

Family

quasar

Version

1.4.1

Botnet

Office04

C2

192.168.1.117:4782

Mutex

a7074e5e-ed13-4240-b2bd-3139cf111cf4

Attributes
  • encryption_key

    B1A93851F2B7AB11E1C412D6A94DD30CC9FC53BD

  • install_name

    Client.exe

  • log_directory

    Logs

  • reconnect_delay

    3000

  • startup_key

    java update

  • 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 1 IoCs
  • Suspicious use of SendNotifyMessage 1 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:5436
    • C:\Windows\SYSTEM32\schtasks.exe
      "schtasks" /create /tn "java update" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\SubDir\Client.exe" /rl HIGHEST /f
      2⤵
      • Scheduled Task/Job: Scheduled Task
      PID:320
    • 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:5852
      • C:\Windows\SYSTEM32\schtasks.exe
        "schtasks" /create /tn "java update" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\SubDir\Client.exe" /rl HIGHEST /f
        3⤵
        • Scheduled Task/Job: Scheduled Task
        PID:5592

Network

MITRE ATT&CK Enterprise v16

Replay Monitor

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Downloads

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

    Filesize

    3.1MB

    MD5

    20e2ad97770afcb29a641ada5db33fe3

    SHA1

    96931794912869c9f83e5e9a091bd290257f5b8b

    SHA256

    3a3fd0e996477049a63b779dda5d31c20ebbae2b8733f3224ee7a2a88350175f

    SHA512

    fc386626fef804a2aa221ebb3f420b7b5c2e63c359b5bdc915d9bc9ad72f8daea025329afd5e381f253635fdda681099a79f72283dbd6d22bfdde6bb519d6ac7

  • memory/5436-0-0x00007FFFF2C23000-0x00007FFFF2C25000-memory.dmp

    Filesize

    8KB

  • memory/5436-1-0x0000000000500000-0x0000000000824000-memory.dmp

    Filesize

    3.1MB

  • memory/5436-2-0x00007FFFF2C20000-0x00007FFFF36E2000-memory.dmp

    Filesize

    10.8MB

  • memory/5436-5-0x00007FFFF2C20000-0x00007FFFF36E2000-memory.dmp

    Filesize

    10.8MB

  • memory/5852-6-0x00007FFFF2C20000-0x00007FFFF36E2000-memory.dmp

    Filesize

    10.8MB

  • memory/5852-7-0x00007FFFF2C20000-0x00007FFFF36E2000-memory.dmp

    Filesize

    10.8MB

  • memory/5852-8-0x000000001C750000-0x000000001C7A0000-memory.dmp

    Filesize

    320KB

  • memory/5852-9-0x000000001C860000-0x000000001C912000-memory.dmp

    Filesize

    712KB

  • memory/5852-10-0x00007FFFF2C20000-0x00007FFFF36E2000-memory.dmp

    Filesize

    10.8MB