Analysis

  • max time kernel
    37s
  • max time network
    38s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20240226-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20240226-enlocale:en-usos:windows10-2004-x64system
  • submitted
    07-04-2024 17:49

Errors

Reason
Machine shutdown

General

  • Target

    Client-built.exe

  • Size

    3.1MB

  • MD5

    145193333e64b74823c421d26f035480

  • SHA1

    f9919b3e81793fc5ccfb48dff30606c08523361c

  • SHA256

    d57cd430c390790a495769b537242d522c25dbec4b01acf7f47b992882c37bfa

  • SHA512

    353b4e0f96f95b0ba553aaecb4b27e53c6d9fe9625547e2d614820aecd4a5103fb1b7a42d0e4eac055404c384e00ee7d046167f86f6743c374a2a9f5813aaf0a

  • SSDEEP

    49152:KvjI22SsaNYfdPBldt698dBcjH361lpoGdVnTHHB72eh2NT:Kvc22SsaNYfdPBldt6+dBcjH361/F

Malware Config

Extracted

Family

quasar

Version

1.4.1

Botnet

Office04

C2

2.tcp.eu.ngrok.io:16096

Mutex

755f883f-4d58-4349-bc9e-f21c4e163b6f

Attributes
  • encryption_key

    EE65D8F2E429F4900E3A17963595716D863A2455

  • install_name

    Client.exe

  • log_directory

    Logs

  • reconnect_delay

    3000

  • startup_key

    Quasar Client Startup

  • subdirectory

    SubDir

Signatures

  • Quasar RAT

    Quasar is an open source Remote Access Tool.

  • Quasar payload 2 IoCs
  • Checks computer location settings 2 TTPs 1 IoCs

    Looks up country code configured in the registry, likely geofence.

  • Executes dropped EXE 1 IoCs
  • Legitimate hosting services abused for malware hosting/C2 1 TTPs 1 IoCs
  • Drops file in System32 directory 2 IoCs
  • Enumerates physical storage devices 1 TTPs

    Attempts to interact with connected storage/optical drive(s).

  • Creates scheduled task(s) 1 TTPs 2 IoCs

    Schtasks is often used by malware for persistence or to perform post-infection execution.

  • Modifies data under HKEY_USERS 15 IoCs
  • Suspicious behavior: EnumeratesProcesses 1 IoCs
  • Suspicious use of AdjustPrivilegeToken 4 IoCs
  • Suspicious use of SetWindowsHookEx 2 IoCs
  • Suspicious use of WriteProcessMemory 8 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:2656
    • C:\Windows\SYSTEM32\schtasks.exe
      "schtasks" /create /tn "Quasar Client Startup" /sc ONLOGON /tr "C:\Windows\system32\SubDir\Client.exe" /rl HIGHEST /f
      2⤵
      • Creates scheduled task(s)
      PID:2756
    • C:\Windows\system32\SubDir\Client.exe
      "C:\Windows\system32\SubDir\Client.exe"
      2⤵
      • Checks computer location settings
      • Executes dropped EXE
      • Suspicious behavior: EnumeratesProcesses
      • Suspicious use of AdjustPrivilegeToken
      • Suspicious use of SetWindowsHookEx
      • Suspicious use of WriteProcessMemory
      PID:3752
      • C:\Windows\SYSTEM32\schtasks.exe
        "schtasks" /create /tn "Quasar Client Startup" /sc ONLOGON /tr "C:\Windows\system32\SubDir\Client.exe" /rl HIGHEST /f
        3⤵
        • Creates scheduled task(s)
        PID:984
      • C:\Windows\System32\shutdown.exe
        "C:\Windows\System32\shutdown.exe" /r /t 0
        3⤵
        • Suspicious use of AdjustPrivilegeToken
        PID:3260
  • C:\Windows\system32\LogonUI.exe
    "LogonUI.exe" /flags:0x4 /state0:0xa39bd055 /state1:0x41c64e6d
    1⤵
    • Modifies data under HKEY_USERS
    • Suspicious use of SetWindowsHookEx
    PID:4548

Network

MITRE ATT&CK Enterprise v15

Replay Monitor

Loading Replay Monitor...

Downloads

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

    Filesize

    3.1MB

    MD5

    145193333e64b74823c421d26f035480

    SHA1

    f9919b3e81793fc5ccfb48dff30606c08523361c

    SHA256

    d57cd430c390790a495769b537242d522c25dbec4b01acf7f47b992882c37bfa

    SHA512

    353b4e0f96f95b0ba553aaecb4b27e53c6d9fe9625547e2d614820aecd4a5103fb1b7a42d0e4eac055404c384e00ee7d046167f86f6743c374a2a9f5813aaf0a

  • memory/2656-8-0x00007FFB77430000-0x00007FFB77EF1000-memory.dmp

    Filesize

    10.8MB

  • memory/2656-1-0x00007FFB77430000-0x00007FFB77EF1000-memory.dmp

    Filesize

    10.8MB

  • memory/2656-2-0x0000000001200000-0x0000000001210000-memory.dmp

    Filesize

    64KB

  • memory/2656-0-0x0000000000690000-0x00000000009B4000-memory.dmp

    Filesize

    3.1MB

  • memory/3752-12-0x000000001B940000-0x000000001B9F2000-memory.dmp

    Filesize

    712KB

  • memory/3752-10-0x000000001B180000-0x000000001B190000-memory.dmp

    Filesize

    64KB

  • memory/3752-11-0x000000001AFA0000-0x000000001AFF0000-memory.dmp

    Filesize

    320KB

  • memory/3752-9-0x00007FFB77430000-0x00007FFB77EF1000-memory.dmp

    Filesize

    10.8MB

  • memory/3752-15-0x000000001B130000-0x000000001B142000-memory.dmp

    Filesize

    72KB

  • memory/3752-16-0x000000001B8C0000-0x000000001B8FC000-memory.dmp

    Filesize

    240KB

  • memory/3752-17-0x00007FFB77430000-0x00007FFB77EF1000-memory.dmp

    Filesize

    10.8MB

  • memory/3752-19-0x000000001B180000-0x000000001B190000-memory.dmp

    Filesize

    64KB

  • memory/3752-18-0x000000001B180000-0x000000001B190000-memory.dmp

    Filesize

    64KB

  • memory/3752-20-0x000000001B180000-0x000000001B190000-memory.dmp

    Filesize

    64KB

  • memory/3752-22-0x00007FFB77430000-0x00007FFB77EF1000-memory.dmp

    Filesize

    10.8MB