Analysis

  • max time kernel
    421s
  • max time network
    425s
  • platform
    windows11-21h2_x64
  • resource
    win11-20240709-en
  • resource tags

    arch:x64arch:x86image:win11-20240709-enlocale:en-usos:windows11-21h2-x64system
  • submitted
    20-07-2024 15:41

General

  • Target

    5a335f4ea90b29144cf268dccdc8f8e1757e57cccc941cc7334b8f4bd7999147.exe

  • Size

    2.0MB

  • MD5

    6e4e01af6b88116f0c7331bba5e7b782

  • SHA1

    756c0a5ea8aac86f41d118166452a011a608043c

  • SHA256

    5a335f4ea90b29144cf268dccdc8f8e1757e57cccc941cc7334b8f4bd7999147

  • SHA512

    f49b6146f313624606a9eb80287c23c68aaefcf7ffafacba83a87b333b4388dd38a423a179b7bcb0e1d555873681b405c781faf68e2d7169fa7bcefe4a73874b

  • SSDEEP

    24576:jYe7C5QSBzoU/n15NuQtG+7IwzwT2wLqq12OBOa2WYO3QFSBztYSqEEU5oZUSzTO:jYemPM0tvmwGBF223ZztBqEqx9v

Malware Config

Signatures

  • DcRat

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

  • Modifies WinLogon for persistence 2 TTPs 3 IoCs
  • Process spawned unexpected child process 9 IoCs

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

  • DCRat payload 2 IoCs

    Detects payload of DCRat, commonly dropped by NSIS installers.

  • Executes dropped EXE 1 IoCs
  • Adds Run key to start application 2 TTPs 6 IoCs
  • Looks up external IP address via web service 1 IoCs

    Uses a legitimate IP lookup service to find the infected system's external IP.

  • Drops file in Program Files directory 3 IoCs
  • Drops file in Windows directory 2 IoCs
  • Enumerates physical storage devices 1 TTPs

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

  • Scheduled Task/Job: Scheduled Task 1 TTPs 9 IoCs

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

  • Suspicious behavior: EnumeratesProcesses 18 IoCs
  • Suspicious use of AdjustPrivilegeToken 2 IoCs
  • Suspicious use of WriteProcessMemory 2 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\5a335f4ea90b29144cf268dccdc8f8e1757e57cccc941cc7334b8f4bd7999147.exe
    "C:\Users\Admin\AppData\Local\Temp\5a335f4ea90b29144cf268dccdc8f8e1757e57cccc941cc7334b8f4bd7999147.exe"
    1⤵
    • Modifies WinLogon for persistence
    • Adds Run key to start application
    • Drops file in Program Files directory
    • Drops file in Windows directory
    • Suspicious behavior: EnumeratesProcesses
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    PID:1484
    • C:\Users\Public\Libraries\dllhost.exe
      "C:\Users\Public\Libraries\dllhost.exe"
      2⤵
      • Executes dropped EXE
      • Suspicious behavior: EnumeratesProcesses
      • Suspicious use of AdjustPrivilegeToken
      PID:4812
  • C:\Windows\system32\schtasks.exe
    schtasks.exe /create /tn "backgroundTaskHostb" /sc MINUTE /mo 14 /tr "'C:\Program Files (x86)\WindowsPowerShell\Modules\backgroundTaskHost.exe'" /f
    1⤵
    • Process spawned unexpected child process
    • Scheduled Task/Job: Scheduled Task
    PID:1952
  • C:\Windows\system32\schtasks.exe
    schtasks.exe /create /tn "backgroundTaskHost" /sc ONLOGON /tr "'C:\Program Files (x86)\WindowsPowerShell\Modules\backgroundTaskHost.exe'" /rl HIGHEST /f
    1⤵
    • Process spawned unexpected child process
    • Scheduled Task/Job: Scheduled Task
    PID:1512
  • C:\Windows\system32\schtasks.exe
    schtasks.exe /create /tn "backgroundTaskHostb" /sc MINUTE /mo 14 /tr "'C:\Program Files (x86)\WindowsPowerShell\Modules\backgroundTaskHost.exe'" /rl HIGHEST /f
    1⤵
    • Process spawned unexpected child process
    • Scheduled Task/Job: Scheduled Task
    PID:2440
  • C:\Windows\system32\schtasks.exe
    schtasks.exe /create /tn "RuntimeBrokerR" /sc MINUTE /mo 13 /tr "'C:\Windows\BrowserCore\en-US\RuntimeBroker.exe'" /f
    1⤵
    • Process spawned unexpected child process
    • Scheduled Task/Job: Scheduled Task
    PID:580
  • C:\Windows\system32\schtasks.exe
    schtasks.exe /create /tn "RuntimeBroker" /sc ONLOGON /tr "'C:\Windows\BrowserCore\en-US\RuntimeBroker.exe'" /rl HIGHEST /f
    1⤵
    • Process spawned unexpected child process
    • Scheduled Task/Job: Scheduled Task
    PID:4468
  • C:\Windows\system32\schtasks.exe
    schtasks.exe /create /tn "RuntimeBrokerR" /sc MINUTE /mo 7 /tr "'C:\Windows\BrowserCore\en-US\RuntimeBroker.exe'" /rl HIGHEST /f
    1⤵
    • Process spawned unexpected child process
    • Scheduled Task/Job: Scheduled Task
    PID:2188
  • C:\Windows\system32\schtasks.exe
    schtasks.exe /create /tn "dllhostd" /sc MINUTE /mo 8 /tr "'C:\Users\Public\Libraries\dllhost.exe'" /f
    1⤵
    • Process spawned unexpected child process
    • Scheduled Task/Job: Scheduled Task
    PID:1608
  • C:\Windows\system32\schtasks.exe
    schtasks.exe /create /tn "dllhost" /sc ONLOGON /tr "'C:\Users\Public\Libraries\dllhost.exe'" /rl HIGHEST /f
    1⤵
    • Process spawned unexpected child process
    • Scheduled Task/Job: Scheduled Task
    PID:4692
  • C:\Windows\system32\schtasks.exe
    schtasks.exe /create /tn "dllhostd" /sc MINUTE /mo 11 /tr "'C:\Users\Public\Libraries\dllhost.exe'" /rl HIGHEST /f
    1⤵
    • Process spawned unexpected child process
    • Scheduled Task/Job: Scheduled Task
    PID:4544

Network

MITRE ATT&CK Enterprise v15

Replay Monitor

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Downloads

  • C:\Users\Public\Libraries\dllhost.exe

    Filesize

    2.0MB

    MD5

    6e4e01af6b88116f0c7331bba5e7b782

    SHA1

    756c0a5ea8aac86f41d118166452a011a608043c

    SHA256

    5a335f4ea90b29144cf268dccdc8f8e1757e57cccc941cc7334b8f4bd7999147

    SHA512

    f49b6146f313624606a9eb80287c23c68aaefcf7ffafacba83a87b333b4388dd38a423a179b7bcb0e1d555873681b405c781faf68e2d7169fa7bcefe4a73874b

  • memory/1484-6-0x000000001BC70000-0x000000001BC7C000-memory.dmp

    Filesize

    48KB

  • memory/1484-2-0x00007FFE01C30000-0x00007FFE026F2000-memory.dmp

    Filesize

    10.8MB

  • memory/1484-3-0x00000000031A0000-0x00000000031AE000-memory.dmp

    Filesize

    56KB

  • memory/1484-5-0x000000001C8E0000-0x000000001C936000-memory.dmp

    Filesize

    344KB

  • memory/1484-4-0x000000001BC60000-0x000000001BC68000-memory.dmp

    Filesize

    32KB

  • memory/1484-0-0x00007FFE01C33000-0x00007FFE01C35000-memory.dmp

    Filesize

    8KB

  • memory/1484-7-0x000000001C930000-0x000000001C93C000-memory.dmp

    Filesize

    48KB

  • memory/1484-8-0x000000001CB40000-0x000000001CB4C000-memory.dmp

    Filesize

    48KB

  • memory/1484-11-0x00007FFE01C30000-0x00007FFE026F2000-memory.dmp

    Filesize

    10.8MB

  • memory/1484-12-0x00007FFE01C30000-0x00007FFE026F2000-memory.dmp

    Filesize

    10.8MB

  • memory/1484-13-0x00007FFE01C30000-0x00007FFE026F2000-memory.dmp

    Filesize

    10.8MB

  • memory/1484-1-0x0000000000EA0000-0x00000000010AE000-memory.dmp

    Filesize

    2.1MB

  • memory/1484-29-0x00007FFE01C30000-0x00007FFE026F2000-memory.dmp

    Filesize

    10.8MB