Analysis

  • max time kernel
    150s
  • max time network
    153s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20220414-en
  • submitted
    17/04/2022, 03:41

General

  • Target
    c9f428ba2c75e97507c3f0a24d44f02e.exe
  • Size 2.5MB
  • Sample220417-d8rtrsheaq
  • SHA256 f4c480507a92330a160dc69769a67d57ff95daea0bd9cd94c914184472b8bbf9
  • MD5 SHA1 SHA512

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 6 IoCs
  • Process spawned unexpected child process 24 IoCs

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

  • UAC bypass 3 TTPs
  • suricata: ET MALWARE DCRAT Activity (GET)

    suricata: ET MALWARE DCRAT Activity (GET)

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

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

  • Reads user/profile data of web browsers 2 TTPs

    Infostealers often target stored browser data, which can include saved credentials etc.

  • Adds Run key to start application 2 TTPs 6 IoCs
  • Checks whether UAC is enabled 1 TTPs 4 IoCs
  • Drops file in Program Files directory 5 IoCs
  • Drops file in Windows directory 10 IoCs
  • Enumerates physical storage devices 1 TTPs

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

  • Creates scheduled task(s) 1 TTPs 24 IoCs

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

  • Modifies registry class 2 IoCs
  • Suspicious behavior: EnumeratesProcesses 44 IoCs
  • Suspicious behavior: GetForegroundWindowSpam 1 IoCs
  • Suspicious use of AdjustPrivilegeToken 5 IoCs
  • Suspicious use of WriteProcessMemory 10 IoCs
  • System policy modification 1 TTPs 6 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\c9f428ba2c75e97507c3f0a24d44f02e.exe
    "C:\Users\Admin\AppData\Local\Temp\c9f428ba2c75e97507c3f0a24d44f02e.exe"
    1⤵
    • Modifies WinLogon for persistence
    • Checks computer location settings
    • Adds Run key to start application
    • Checks whether UAC is enabled
    • Drops file in Program Files directory
    • Drops file in Windows directory
    • Modifies registry class
    • Suspicious behavior: EnumeratesProcesses
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    • System policy modification
    PID:4808
    • C:\Windows\System32\cmd.exe
      "C:\Windows\System32\cmd.exe" /C "C:\Users\Admin\AppData\Local\Temp\qrXfpsIjp7.bat"
      2⤵
      • Suspicious use of WriteProcessMemory
      PID:4108
      • C:\Windows\system32\w32tm.exe
        w32tm /stripchart /computer:localhost /period:5 /dataonly /samples:2
        3⤵
          PID:4728
        • C:\ProgramData\Mozilla\updates\308046B0AF4A39CB\winlogon.exe
          "C:\ProgramData\Mozilla\updates\308046B0AF4A39CB\winlogon.exe"
          3⤵
          • Executes dropped EXE
          • Checks computer location settings
          • Checks whether UAC is enabled
          • Modifies registry class
          • Suspicious behavior: EnumeratesProcesses
          • Suspicious behavior: GetForegroundWindowSpam
          • Suspicious use of AdjustPrivilegeToken
          • Suspicious use of WriteProcessMemory
          • System policy modification
          PID:4604
          • C:\Windows\System32\WScript.exe
            "C:\Windows\System32\WScript.exe" "C:\Users\Admin\AppData\Local\Temp\0bfcc6f2-7202-4b65-bd45-714263bccd82.vbs"
            4⤵
              PID:4264
            • C:\Windows\System32\WScript.exe
              "C:\Windows\System32\WScript.exe" "C:\Users\Admin\AppData\Local\Temp\200f0352-7300-4378-b224-dfb16a482fb5.vbs"
              4⤵
                PID:3252
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "winlogon" /sc MINUTE /mo 6 /tr "'C:\ProgramData\Mozilla\updates\308046B0AF4A39CB\winlogon.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:4968
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "winlogon" /sc ONLOGON /tr "'C:\ProgramData\Mozilla\updates\308046B0AF4A39CB\winlogon.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:4352
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "winlogon" /sc ONSTART /tr "'C:\ProgramData\Mozilla\updates\308046B0AF4A39CB\winlogon.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:1860
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "winlogonw" /sc MINUTE /mo 12 /tr "'C:\ProgramData\Mozilla\updates\308046B0AF4A39CB\winlogon.exe'" /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:884
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "fontdrvhost" /sc MINUTE /mo 14 /tr "'C:\Windows\Installer\{AC76BA86-7AD7-1033-7B44-AC0F074E4100}\fontdrvhost.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:1136
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "fontdrvhost" /sc ONLOGON /tr "'C:\Windows\Installer\{AC76BA86-7AD7-1033-7B44-AC0F074E4100}\fontdrvhost.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:1448
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "fontdrvhost" /sc ONSTART /tr "'C:\Windows\Installer\{AC76BA86-7AD7-1033-7B44-AC0F074E4100}\fontdrvhost.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:2656
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "fontdrvhostf" /sc MINUTE /mo 8 /tr "'C:\Windows\Installer\{AC76BA86-7AD7-1033-7B44-AC0F074E4100}\fontdrvhost.exe'" /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:1944
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "services" /sc MINUTE /mo 11 /tr "'C:\Windows\ShellComponents\services.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:2712
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "services" /sc ONLOGON /tr "'C:\Windows\ShellComponents\services.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:3260
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "services" /sc ONSTART /tr "'C:\Windows\ShellComponents\services.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:392
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "servicess" /sc MINUTE /mo 13 /tr "'C:\Windows\ShellComponents\services.exe'" /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:5020
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "wininit" /sc MINUTE /mo 12 /tr "'C:\Users\Admin\Contacts\wininit.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:3856
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "wininit" /sc ONLOGON /tr "'C:\Users\Admin\Contacts\wininit.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:4960
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "wininit" /sc ONSTART /tr "'C:\Users\Admin\Contacts\wininit.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:4240
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "wininitw" /sc MINUTE /mo 13 /tr "'C:\Users\Admin\Contacts\wininit.exe'" /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:2928
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "fontdrvhost" /sc MINUTE /mo 5 /tr "'C:\Recovery\WindowsRE\fontdrvhost.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:4660
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "fontdrvhost" /sc ONLOGON /tr "'C:\Recovery\WindowsRE\fontdrvhost.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:4292
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "fontdrvhost" /sc ONSTART /tr "'C:\Recovery\WindowsRE\fontdrvhost.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:3720
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "fontdrvhostf" /sc MINUTE /mo 7 /tr "'C:\Recovery\WindowsRE\fontdrvhost.exe'" /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:3688
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "fontdrvhost" /sc MINUTE /mo 8 /tr "'C:\Program Files\MSBuild\Microsoft\fontdrvhost.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:2768
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "fontdrvhost" /sc ONLOGON /tr "'C:\Program Files\MSBuild\Microsoft\fontdrvhost.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:4764
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "fontdrvhost" /sc ONSTART /tr "'C:\Program Files\MSBuild\Microsoft\fontdrvhost.exe'" /rl HIGHEST /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:3624
        • C:\Windows\system32\schtasks.exe
          schtasks.exe /create /tn "fontdrvhostf" /sc MINUTE /mo 12 /tr "'C:\Program Files\MSBuild\Microsoft\fontdrvhost.exe'" /f
          1⤵
          • Process spawned unexpected child process
          • Creates scheduled task(s)
          PID:2392
        • C:\Windows\system32\vssvc.exe
          C:\Windows\system32\vssvc.exe
          1⤵
          • Suspicious use of AdjustPrivilegeToken
          PID:1100
        • C:\Windows\system32\wbem\WmiApSrv.exe
          C:\Windows\system32\wbem\WmiApSrv.exe
          1⤵
            PID:3460

          Network

                MITRE ATT&CK Enterprise v6

                Replay Monitor

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                Downloads

                winlogon.exe

                • Path C:\ProgramData\Mozilla\updates\308046B0AF4A39CB\winlogon.exe
                • Size 2.5MB
                • SHA256 88f2717203a870618cc3a73315c1bdd0842227c300211f7fb0ad04cfee79b6de
                • MD5 SHA1 SHA512 SSDEEP

                winlogon.exe

                • Path C:\ProgramData\Mozilla\updates\308046B0AF4A39CB\winlogon.exe
                • Size 2.5MB
                • SHA256 88f2717203a870618cc3a73315c1bdd0842227c300211f7fb0ad04cfee79b6de
                • MD5 SHA1 SHA512 SSDEEP

                0bfcc6f2-7202-4b65-bd45-714263bccd82.vbs

                • Path C:\Users\Admin\AppData\Local\Temp\0bfcc6f2-7202-4b65-bd45-714263bccd82.vbs
                • Size 736B
                • SHA256 e6b38dd2f11b2995d1bc90eb149ff4adaded1c7813fc947a8a8e0a09588b4968
                • MD5 SHA1 SHA512

                200f0352-7300-4378-b224-dfb16a482fb5.vbs

                • Path C:\Users\Admin\AppData\Local\Temp\200f0352-7300-4378-b224-dfb16a482fb5.vbs
                • Size 512B
                • SHA256 67a36577f4ec12d4a5c29f4c4524243b48b0d88eb5a13ceb390b03d0bc91034d
                • MD5 SHA1 SHA512

                qrXfpsIjp7.bat

                • Path C:\Users\Admin\AppData\Local\Temp\qrXfpsIjp7.bat
                • Size 224B
                • SHA256 2423aab64fdf46c3710bf1f0be35e7cfa859ec5898dd0689053829bb320ba191
                • MD5 SHA1 SHA512

                memory/4604-140-0x0000000000360000-0x00000000005DE000-memory.dmp

                memory/4604-141-0x00007FF8C0C90000-0x00007FF8C1751000-memory.dmp

                memory/4604-142-0x000000001B230000-0x000000001B232000-memory.dmp

                memory/4808-130-0x0000000000E00000-0x000000000107E000-memory.dmp

                memory/4808-133-0x000000001C4B0000-0x000000001C500000-memory.dmp

                memory/4808-131-0x00007FF8C0C90000-0x00007FF8C1751000-memory.dmp

                memory/4808-132-0x0000000003170000-0x0000000003172000-memory.dmp