Analysis

  • max time kernel
    142s
  • max time network
    150s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20231215-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20231215-enlocale:en-usos:windows10-2004-x64system
  • submitted
    04/02/2024, 22:42

General

  • Target
    built.exe
  • Size 3.1MB
  • Sample240204-2mwslaedfn
  • SHA256 ede3b90a03e2913e849d84264701d4c8831b739d5c34588bd36c888ff9810fac
  • MD5 SHA1 SHA512 SSDEEP

Malware Config

Extracted

Family
  • quasar

Version
  • 1.4.1

Botnet
  • Office04

C2
  • quasar.adminer.eu.org:80

Mutex
  • c00a57b8-6458-402d-95e1-ebeda04e5125

Attributes
  • encryption_key

    FEBC5C854FD21C7823AA8692AFBDC1DA8AE24AEC

  • install_name

    Client.exe

  • log_directory

    Logs

  • reconnect_delay

    3000

  • startup_key

    Client Startup

  • subdirectory

    SubDir

Signatures

  • Quasar RAT

    Quasar is an open source Remote Access Tool.

  • Quasar payload 3 IoCs
  • Executes dropped EXE 1 IoCs
  • Creates scheduled task(s) 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 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\built.exe
    "C:\Users\Admin\AppData\Local\Temp\built.exe"
    1⤵
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    PID:4028
    • C:\Windows\SYSTEM32\schtasks.exe
      "schtasks" /create /tn "Client Startup" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\SubDir\Client.exe" /rl HIGHEST /f
      2⤵
      • Creates scheduled task(s)
      PID:4664
    • 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 WriteProcessMemory
      PID:4944
      • C:\Windows\SYSTEM32\schtasks.exe
        "schtasks" /create /tn "Client Startup" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\SubDir\Client.exe" /rl HIGHEST /f
        3⤵
        • Creates scheduled task(s)
        PID:4880

Network

        MITRE ATT&CK Enterprise v15

        Replay Monitor

        Loading Replay Monitor...

        Downloads

        Client.exe

        • Path C:\Users\Admin\AppData\Roaming\SubDir\Client.exe
        • Size 398KB
        • SHA256 130d40b196b632c67f23e65c9aae3f3cbf5266b25439d9b81bdd9ca71bb919e5
        • MD5 SHA1 SHA512 SSDEEP

        Client.exe

        • Path C:\Users\Admin\AppData\Roaming\SubDir\Client.exe
        • Size 471KB
        • SHA256 ee256a0d2ca62b1f81858bed0a5237ec8a94ad6cbbc4cdec505eb688b7505aa2
        • MD5 SHA1 SHA512 SSDEEP

        memory/4028-0-0x0000000000AE0000-0x0000000000E04000-memory.dmp

        memory/4028-1-0x00007FFBA7B50000-0x00007FFBA8611000-memory.dmp

        memory/4028-2-0x000000001B980000-0x000000001B990000-memory.dmp

        memory/4028-10-0x00007FFBA7B50000-0x00007FFBA8611000-memory.dmp

        memory/4944-9-0x00007FFBA7B50000-0x00007FFBA8611000-memory.dmp

        memory/4944-11-0x0000000001190000-0x00000000011A0000-memory.dmp

        memory/4944-12-0x0000000002B30000-0x0000000002B80000-memory.dmp

        memory/4944-13-0x000000001BCA0000-0x000000001BD52000-memory.dmp

        memory/4944-14-0x00007FFBA7B50000-0x00007FFBA8611000-memory.dmp

        memory/4944-15-0x0000000001190000-0x00000000011A0000-memory.dmp