Analysis

  • max time kernel
    1795s
  • max time network
    1804s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20240319-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20240319-enlocale:en-usos:windows10-2004-x64system
  • submitted
    31/03/2024, 00:39

General

  • Target

    Client-built.exe

  • Size

    3.1MB

  • MD5

    57045c2bf3377b12aa5abce21cc0a99d

  • SHA1

    217202ed404f25fc550ad70fd7066b0fe8773ef9

  • SHA256

    f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2

  • SHA512

    9ab46cc194eeaabb75777457a01328f5a8d2ebf604efba0623575cf25c04e206e416ee72db17e3c92a9d363330f82fa3ce2aac64c2a4a61d4dce34d79b73366e

  • SSDEEP

    49152:Wv+I22SsaNYfdPBldt698dBcjHukuQPoGdhEQTHHB72eh2NT:Wvz22SsaNYfdPBldt6+dBcjHukuE

Malware Config

Extracted

Family

quasar

Version

1.4.1

Botnet

Ratted

C2

140.238.91.110:44867

Mutex

be049c71-d631-4f68-8b3e-8e01081f2340

Attributes
  • encryption_key

    AA883CE7347A3543F81EBCDE3BBF3BFC9C60344E

  • install_name

    WOS64UPD.exe

  • log_directory

    Windows Update Logs

  • reconnect_delay

    3000

  • startup_key

    Windows Updater

  • subdirectory

    Windows

Signatures

  • Quasar RAT

    Quasar is an open source Remote Access Tool.

  • Quasar payload 2 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 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⤵
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    PID:4276
    • C:\Windows\SYSTEM32\schtasks.exe
      "schtasks" /create /tn "Windows Updater" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe" /rl HIGHEST /f
      2⤵
      • Creates scheduled task(s)
      PID:1080
    • C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe
      "C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe"
      2⤵
      • Executes dropped EXE
      • Suspicious use of AdjustPrivilegeToken
      • Suspicious use of SetWindowsHookEx
      • Suspicious use of WriteProcessMemory
      PID:4820
      • C:\Windows\SYSTEM32\schtasks.exe
        "schtasks" /create /tn "Windows Updater" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe" /rl HIGHEST /f
        3⤵
        • Creates scheduled task(s)
        PID:2476
  • 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=4084 --field-trial-handle=2276,i,5672504106535478802,17394903851940863593,262144 --variations-seed-version /prefetch:8
    1⤵
      PID:4936
    • 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=3680 --field-trial-handle=2276,i,5672504106535478802,17394903851940863593,262144 --variations-seed-version /prefetch:8
      1⤵
        PID:5028

      Network

      MITRE ATT&CK Enterprise v15

      Replay Monitor

      Loading Replay Monitor...

      Downloads

      • C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe

        Filesize

        3.1MB

        MD5

        57045c2bf3377b12aa5abce21cc0a99d

        SHA1

        217202ed404f25fc550ad70fd7066b0fe8773ef9

        SHA256

        f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2

        SHA512

        9ab46cc194eeaabb75777457a01328f5a8d2ebf604efba0623575cf25c04e206e416ee72db17e3c92a9d363330f82fa3ce2aac64c2a4a61d4dce34d79b73366e

      • memory/4276-0-0x0000000000790000-0x0000000000AB4000-memory.dmp

        Filesize

        3.1MB

      • memory/4276-1-0x00007FFC40560000-0x00007FFC41021000-memory.dmp

        Filesize

        10.8MB

      • memory/4276-2-0x000000001B780000-0x000000001B790000-memory.dmp

        Filesize

        64KB

      • memory/4276-9-0x00007FFC40560000-0x00007FFC41021000-memory.dmp

        Filesize

        10.8MB

      • memory/4820-10-0x00000000032C0000-0x00000000032D0000-memory.dmp

        Filesize

        64KB

      • memory/4820-8-0x00007FFC40560000-0x00007FFC41021000-memory.dmp

        Filesize

        10.8MB

      • memory/4820-11-0x000000001C9F0000-0x000000001CA40000-memory.dmp

        Filesize

        320KB

      • memory/4820-12-0x000000001CB00000-0x000000001CBB2000-memory.dmp

        Filesize

        712KB

      • memory/4820-15-0x000000001CA80000-0x000000001CA92000-memory.dmp

        Filesize

        72KB

      • memory/4820-16-0x000000001D200000-0x000000001D23C000-memory.dmp

        Filesize

        240KB

      • memory/4820-17-0x00007FFC40560000-0x00007FFC41021000-memory.dmp

        Filesize

        10.8MB

      • memory/4820-18-0x00000000032C0000-0x00000000032D0000-memory.dmp

        Filesize

        64KB