Analysis

  • max time kernel
    149s
  • max time network
    157s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20240226-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20240226-enlocale:en-usos:windows10-2004-x64system
  • submitted
    30/03/2024, 03:15

General

  • Target

    Client-built.exe

  • Size

    3.3MB

  • MD5

    eff096752ef1895d626f570a154c38a2

  • SHA1

    ae2c737e15d12d830220bae198b72717422d70d4

  • SHA256

    46297c4c0a1e8dcbffcc89326acc44e75720a62569242a804be88ea915fe4c8e

  • SHA512

    1c0cba459290f89874adab22697c62d9ebe15f41c68b2efa0d004a9e12b1cd4676480e35a04a3dbe9e4cdec59cbc7a2f1e7b5b30da856bf16052c8f958c8a52d

  • SSDEEP

    49152:rvBt62XlaSFNWPjljiFa2RoUYInlDkE2Hqk/+FWoGd++THHB72eh2NTfZqS:rvr62XlaSFNWPjljiFXRoUYInlDLEO

Malware Config

Extracted

Family

quasar

Version

1.4.1

Botnet

Office01

C2

198.7.62.204:4782

Mutex

02b9c972-8b55-4d55-b7c4-09a1f00ff400

Attributes
  • encryption_key

    5BF0703F288C43118835CAF4D1A6879C29016FB3

  • 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 2 IoCs
  • Executes dropped EXE 1 IoCs
  • Drops file in System32 directory 5 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 SetWindowsHookEx 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⤵
    • Drops file in System32 directory
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    PID:5076
    • C:\Windows\SYSTEM32\schtasks.exe
      "schtasks" /create /tn "Client Startup" /sc ONLOGON /tr "C:\Windows\system32\SubDir\Client.exe" /rl HIGHEST /f
      2⤵
      • Creates scheduled task(s)
      PID:4288
    • C:\Windows\system32\SubDir\Client.exe
      "C:\Windows\system32\SubDir\Client.exe"
      2⤵
      • Executes dropped EXE
      • Drops file in System32 directory
      • Suspicious use of AdjustPrivilegeToken
      • Suspicious use of SetWindowsHookEx
      • Suspicious use of WriteProcessMemory
      PID:2280
      • C:\Windows\SYSTEM32\schtasks.exe
        "schtasks" /create /tn "Client Startup" /sc ONLOGON /tr "C:\Windows\system32\SubDir\Client.exe" /rl HIGHEST /f
        3⤵
        • Creates scheduled task(s)
        PID:2260
  • C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe
    "C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe" --type=utility --utility-sub-type=asset_store.mojom.AssetStoreService --lang=en-US --service-sandbox-type=asset_store_service --no-appcompat-clear --mojo-platform-channel-handle=3976 --field-trial-handle=2900,i,14549994492153927475,12895178890800740987,262144 --variations-seed-version /prefetch:8
    1⤵
      PID:500

    Network

    MITRE ATT&CK Enterprise v15

    Replay Monitor

    Loading Replay Monitor...

    Downloads

    • C:\Windows\System32\SubDir\Client.exe

      Filesize

      3.3MB

      MD5

      eff096752ef1895d626f570a154c38a2

      SHA1

      ae2c737e15d12d830220bae198b72717422d70d4

      SHA256

      46297c4c0a1e8dcbffcc89326acc44e75720a62569242a804be88ea915fe4c8e

      SHA512

      1c0cba459290f89874adab22697c62d9ebe15f41c68b2efa0d004a9e12b1cd4676480e35a04a3dbe9e4cdec59cbc7a2f1e7b5b30da856bf16052c8f958c8a52d

    • memory/2280-10-0x00007FFE89DA0000-0x00007FFE8A861000-memory.dmp

      Filesize

      10.8MB

    • memory/2280-11-0x000000001BE30000-0x000000001BE40000-memory.dmp

      Filesize

      64KB

    • memory/2280-12-0x0000000003200000-0x0000000003250000-memory.dmp

      Filesize

      320KB

    • memory/2280-13-0x000000001C9F0000-0x000000001CAA2000-memory.dmp

      Filesize

      712KB

    • memory/2280-14-0x00007FFE89DA0000-0x00007FFE8A861000-memory.dmp

      Filesize

      10.8MB

    • memory/2280-15-0x000000001BE30000-0x000000001BE40000-memory.dmp

      Filesize

      64KB

    • memory/5076-0-0x0000000000820000-0x0000000000B68000-memory.dmp

      Filesize

      3.3MB

    • memory/5076-1-0x00007FFE89DA0000-0x00007FFE8A861000-memory.dmp

      Filesize

      10.8MB

    • memory/5076-2-0x000000001B9A0000-0x000000001B9B0000-memory.dmp

      Filesize

      64KB

    • memory/5076-9-0x00007FFE89DA0000-0x00007FFE8A861000-memory.dmp

      Filesize

      10.8MB