Analysis

  • max time kernel
    149s
  • max time network
    148s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20231222-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20231222-enlocale:en-usos:windows10-2004-x64system
  • submitted
    05/02/2024, 09:08

General

  • Target
    Client-built2.exe
  • Size 3.1MB
  • Sample240205-k34ppscca2
  • SHA256 989f8844b3bd86c1fd08d9aca9a1e03a25d3e7182d800ac749bf1b07b5be9e0c
  • 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\Client-built2.exe
    "C:\Users\Admin\AppData\Local\Temp\Client-built2.exe"
    1⤵
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    PID:4352
    • 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:2428
    • 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:4624
      • 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:3504

Network

        MITRE ATT&CK Enterprise v15

        Replay Monitor

        Loading Replay Monitor...

        Downloads

        Client.exe

        • Path C:\Users\Admin\AppData\Roaming\SubDir\Client.exe
        • Size 468KB
        • SHA256 80cb7d34e86ca0a4a10000a4b4fa79ad21392e35244962013be89371a49c1c48
        • MD5 SHA1 SHA512 SSDEEP

        Client.exe

        • Path C:\Users\Admin\AppData\Roaming\SubDir\Client.exe
        • Size 588KB
        • SHA256 bb7698f11cc8abc2c506d618abe10964af6726e196e8db06ee544d297bb04ea9
        • MD5 SHA1 SHA512 SSDEEP

        memory/4352-0-0x00000000009B0000-0x0000000000CD4000-memory.dmp

        memory/4352-1-0x00007FFAD5D20000-0x00007FFAD67E1000-memory.dmp

        memory/4352-2-0x000000001B7D0000-0x000000001B7E0000-memory.dmp

        memory/4352-10-0x00007FFAD5D20000-0x00007FFAD67E1000-memory.dmp

        memory/4624-9-0x00007FFAD5D20000-0x00007FFAD67E1000-memory.dmp

        memory/4624-11-0x000000001B910000-0x000000001B960000-memory.dmp

        memory/4624-12-0x000000001D8D0000-0x000000001D982000-memory.dmp

        memory/4624-13-0x00007FFAD5D20000-0x00007FFAD67E1000-memory.dmp

        memory/4624-14-0x000000001B9A0000-0x000000001B9B0000-memory.dmp