Analysis

  • max time kernel
    178s
  • max time network
    191s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-en-20220112
  • submitted
    09-02-2022 03:36

General

  • Target

    a77873bfea27896f94731478d64541a3.exe

  • Size

    873KB

  • MD5

    a77873bfea27896f94731478d64541a3

  • SHA1

    9d9596b12d51e06dd1c509c3df0cb7432fb60156

  • SHA256

    0c70ff796c9a6c8e20437dcd29e1be3951ac7dae8bc0e75bbbae5b710c6be70e

  • SHA512

    34c94a9e432bb0d4e2154ca80d2a42bb47e4a3ff29a5ecb9d24eb4db235a3dfb7e6c532edb05bcb4a1e299c4b040e39d2c0eeeac8593e7b0babcdaf834e49a0e

Malware Config

Signatures

  • DcRat 11 IoCs

    DarkCrystal(DC) is a new .NET RAT active since June 2019 capable of loading additional plugins.

  • Process spawned unexpected child process 7 IoCs

    This typically indicates the parent process was compromised via an exploit or macro.

  • Executes dropped EXE 1 IoCs
  • Checks computer location settings 2 TTPs 1 IoCs

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

  • Adds Run key to start application 2 TTPs 7 IoCs
  • Drops file in System32 directory 8 IoCs
  • Drops file in Program Files directory 3 IoCs
  • Enumerates physical storage devices 1 TTPs

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

  • Checks processor information in registry 2 TTPs 2 IoCs

    Processor information is often read in order to detect sandboxing environments.

  • Creates scheduled task(s) 1 TTPs 7 IoCs

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

  • Suspicious behavior: EnumeratesProcesses 11 IoCs
  • Suspicious use of AdjustPrivilegeToken 2 IoCs
  • Suspicious use of WriteProcessMemory 2 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\a77873bfea27896f94731478d64541a3.exe
    "C:\Users\Admin\AppData\Local\Temp\a77873bfea27896f94731478d64541a3.exe"
    1⤵
    • DcRat
    • Checks computer location settings
    • Adds Run key to start application
    • Drops file in System32 directory
    • Drops file in Program Files directory
    • Suspicious behavior: EnumeratesProcesses
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    PID:984
    • C:\Program Files\Microsoft Office\Updates\Download\PackageFiles\MoUsoCoreWorker.exe
      "C:\Program Files\Microsoft Office\Updates\Download\PackageFiles\MoUsoCoreWorker.exe"
      2⤵
      • Executes dropped EXE
      • Suspicious behavior: EnumeratesProcesses
      • Suspicious use of AdjustPrivilegeToken
      PID:1580
  • C:\Windows\system32\schtasks.exe
    schtasks.exe /create /tn "MoUsoCoreWorker" /sc ONLOGON /tr "'C:\Program Files\Microsoft Office\Updates\Download\PackageFiles\MoUsoCoreWorker.exe'" /rl HIGHEST /f
    1⤵
    • DcRat
    • Process spawned unexpected child process
    • Creates scheduled task(s)
    PID:3276
  • C:\Windows\system32\schtasks.exe
    schtasks.exe /create /tn "services" /sc ONLOGON /tr "'C:\Users\Public\services.exe'" /rl HIGHEST /f
    1⤵
    • DcRat
    • Process spawned unexpected child process
    • Creates scheduled task(s)
    PID:916
  • C:\Windows\system32\schtasks.exe
    schtasks.exe /create /tn "fontdrvhost" /sc ONLOGON /tr "'C:\PerfLogs\fontdrvhost.exe'" /rl HIGHEST /f
    1⤵
    • DcRat
    • Process spawned unexpected child process
    • Creates scheduled task(s)
    PID:3200
  • C:\Windows\system32\schtasks.exe
    schtasks.exe /create /tn "RuntimeBroker" /sc ONLOGON /tr "'C:\Windows\System32\mfcore\RuntimeBroker.exe'" /rl HIGHEST /f
    1⤵
    • DcRat
    • Process spawned unexpected child process
    • Creates scheduled task(s)
    PID:776
  • C:\Windows\system32\schtasks.exe
    schtasks.exe /create /tn "lsass" /sc ONLOGON /tr "'C:\Windows\System32\MSPhotography\lsass.exe'" /rl HIGHEST /f
    1⤵
    • DcRat
    • Process spawned unexpected child process
    • Creates scheduled task(s)
    PID:3252
  • C:\Windows\system32\schtasks.exe
    schtasks.exe /create /tn "MoUsoCoreWorker" /sc ONLOGON /tr "'C:\Windows\System32\BthpanContextHandler\MoUsoCoreWorker.exe'" /rl HIGHEST /f
    1⤵
    • DcRat
    • Process spawned unexpected child process
    • Creates scheduled task(s)
    PID:3300
  • C:\Windows\system32\schtasks.exe
    schtasks.exe /create /tn "sihost" /sc ONLOGON /tr "'C:\Windows\System32\mspatcha\sihost.exe'" /rl HIGHEST /f
    1⤵
    • DcRat
    • Process spawned unexpected child process
    • Creates scheduled task(s)
    PID:2692
  • C:\Windows\system32\MusNotifyIcon.exe
    %systemroot%\system32\MusNotifyIcon.exe NotifyTrayIcon 13
    1⤵
    • Checks processor information in registry
    PID:760
  • C:\Windows\System32\svchost.exe
    C:\Windows\System32\svchost.exe -k NetworkService -p
    1⤵
      PID:2432

    Network

    MITRE ATT&CK Enterprise v6

    Replay Monitor

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    Downloads

    • memory/984-130-0x00007FFB34D53000-0x00007FFB34D55000-memory.dmp

      Filesize

      8KB

    • memory/984-131-0x00000000003A0000-0x0000000000482000-memory.dmp

      Filesize

      904KB

    • memory/984-132-0x0000000002440000-0x0000000002442000-memory.dmp

      Filesize

      8KB

    • memory/1580-135-0x00007FFB34D53000-0x00007FFB34D55000-memory.dmp

      Filesize

      8KB

    • memory/1580-136-0x000000001D090000-0x000000001D092000-memory.dmp

      Filesize

      8KB