Analysis

  • max time kernel
    150s
  • max time network
    112s
  • platform
    windows10_x64
  • resource
    win10v20201028
  • submitted
    14-12-2020 16:25

General

  • Target

    c276255be8c317392e43735e0f707cf9.exe

  • Size

    1.3MB

  • MD5

    c276255be8c317392e43735e0f707cf9

  • SHA1

    8deb38349ef9978a83b8fee521de5e06d2b86052

  • SHA256

    5fe7d9e94105fcb2dd524faee708442a10c98a98c9ea3b6ef35da17b6f7f4f47

  • SHA512

    ebb335783435b6675751d9efaeb601874df6a21f41f9ac0877afc7ab19a5ef7287fa4f8fc81984396a6ff5e29c5a40449635745e3d51a254096d53398b2dd1a3

Malware Config

Signatures

  • Darkcomet

    DarkComet is a remote access trojan (RAT) developed by Jean-Pierre Lesueur.

  • Modifies WinLogon for persistence 2 TTPs 1 IoCs
  • Modifies firewall policy service 2 TTPs 3 IoCs
  • Modifies security service 2 TTPs 1 IoCs
  • Windows security bypass 2 TTPs
  • Disables RegEdit via registry modification
  • Disables Task Manager via registry modification
  • Executes dropped EXE 3 IoCs
  • Sets file to hidden 1 TTPs

    Modifies file attributes to stop it showing in Explorer etc.

  • UPX packed file 3 IoCs

    Detects executables packed with UPX/modified UPX open source packer.

  • Checks computer location settings 2 TTPs 1 IoCs

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

  • Deletes itself 1 IoCs
  • Windows security modification 2 TTPs 2 IoCs
  • Adds Run key to start application 2 TTPs 2 IoCs
  • Checks whether UAC is enabled 1 TTPs 2 IoCs
  • Drops file in System32 directory 4 IoCs
  • Enumerates physical storage devices 1 TTPs

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

  • Modifies registry class 1 IoCs
  • Suspicious behavior: GetForegroundWindowSpam 1 IoCs
  • Suspicious use of AdjustPrivilegeToken 49 IoCs
  • Suspicious use of SetWindowsHookEx 1 IoCs
  • Suspicious use of WriteProcessMemory 60 IoCs
  • System policy modification 1 TTPs 3 IoCs
  • Views/modifies file attributes 1 TTPs 2 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\c276255be8c317392e43735e0f707cf9.exe
    "C:\Users\Admin\AppData\Local\Temp\c276255be8c317392e43735e0f707cf9.exe"
    1⤵
    • Modifies WinLogon for persistence
    • Checks computer location settings
    • Adds Run key to start application
    • Modifies registry class
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    PID:4032
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" /k attrib "C:\Users\Admin\AppData\Local\Temp\c276255be8c317392e43735e0f707cf9.exe" +s +h
      2⤵
      • Suspicious use of WriteProcessMemory
      PID:2920
      • C:\Windows\SysWOW64\attrib.exe
        attrib "C:\Users\Admin\AppData\Local\Temp\c276255be8c317392e43735e0f707cf9.exe" +s +h
        3⤵
        • Views/modifies file attributes
        PID:3944
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" /k attrib "C:\Users\Admin\AppData\Local\Temp" +s +h
      2⤵
      • Suspicious use of WriteProcessMemory
      PID:3484
      • C:\Windows\SysWOW64\attrib.exe
        attrib "C:\Users\Admin\AppData\Local\Temp" +s +h
        3⤵
        • Views/modifies file attributes
        PID:2940
    • C:\Users\Admin\AppData\Local\Temp\RUFUS-3.12.EXE
      "C:\Users\Admin\AppData\Local\Temp\RUFUS-3.12.EXE"
      2⤵
      • Executes dropped EXE
      • Checks whether UAC is enabled
      • Drops file in System32 directory
      • Suspicious use of AdjustPrivilegeToken
      PID:204
    • C:\Windows\SysWOW64\notepad.exe
      notepad
      2⤵
      • Deletes itself
      PID:1012
    • C:\Users\Admin\Documents\MSDCSC\msdcsc.exe
      "C:\Users\Admin\Documents\MSDCSC\msdcsc.exe"
      2⤵
      • Modifies firewall policy service
      • Modifies security service
      • Executes dropped EXE
      • Windows security modification
      • Adds Run key to start application
      • Suspicious behavior: GetForegroundWindowSpam
      • Suspicious use of AdjustPrivilegeToken
      • Suspicious use of SetWindowsHookEx
      • Suspicious use of WriteProcessMemory
      • System policy modification
      PID:520
      • C:\Users\Admin\AppData\Local\Temp\RUFUS-3.12.EXE
        "C:\Users\Admin\AppData\Local\Temp\RUFUS-3.12.EXE"
        3⤵
        • Executes dropped EXE
        • Checks whether UAC is enabled
        PID:2224
      • C:\Windows\SysWOW64\notepad.exe
        notepad
        3⤵
          PID:2768
    • C:\Windows\system32\svchost.exe
      C:\Windows\system32\svchost.exe -k LocalSystemNetworkRestricted -s WPDBusEnum
      1⤵
        PID:588
      • \??\c:\windows\system32\svchost.exe
        c:\windows\system32\svchost.exe -k localsystemnetworkrestricted -s fhsvc
        1⤵
          PID:3428

        Network

        MITRE ATT&CK Matrix ATT&CK v6

        Persistence

        Winlogon Helper DLL

        1
        T1004

        Modify Existing Service

        2
        T1031

        Hidden Files and Directories

        2
        T1158

        Registry Run Keys / Startup Folder

        1
        T1060

        Defense Evasion

        Modify Registry

        7
        T1112

        Disabling Security Tools

        2
        T1089

        Hidden Files and Directories

        2
        T1158

        Discovery

        Query Registry

        1
        T1012

        System Information Discovery

        3
        T1082

        Replay Monitor

        Loading Replay Monitor...

        Downloads

        • C:\Users\Admin\AppData\Local\Temp\RUFUS-3.12.EXE
          MD5

          cd822912b4ff3c303a62d2538fa88d01

          SHA1

          9bf6d9bbc06150a933b4171d55c7a8a297cd9cc5

          SHA256

          f37771fbb9a9747c255bfed791c8d25b170a05390c07b977ceed83fda2930db0

          SHA512

          dc22c5b25f00a707903e09faa17102afa8c7c33c601c4a9e565f0ba1f9be38b2d3fd33d6cd4fb3f106559826e5b2d4830ebb47f454bd211e948abada5bd40bf7

        • C:\Users\Admin\AppData\Local\Temp\RUFUS-3.12.EXE
          MD5

          cd822912b4ff3c303a62d2538fa88d01

          SHA1

          9bf6d9bbc06150a933b4171d55c7a8a297cd9cc5

          SHA256

          f37771fbb9a9747c255bfed791c8d25b170a05390c07b977ceed83fda2930db0

          SHA512

          dc22c5b25f00a707903e09faa17102afa8c7c33c601c4a9e565f0ba1f9be38b2d3fd33d6cd4fb3f106559826e5b2d4830ebb47f454bd211e948abada5bd40bf7

        • C:\Users\Admin\AppData\Local\Temp\RUFUS-3.12.EXE
          MD5

          cd822912b4ff3c303a62d2538fa88d01

          SHA1

          9bf6d9bbc06150a933b4171d55c7a8a297cd9cc5

          SHA256

          f37771fbb9a9747c255bfed791c8d25b170a05390c07b977ceed83fda2930db0

          SHA512

          dc22c5b25f00a707903e09faa17102afa8c7c33c601c4a9e565f0ba1f9be38b2d3fd33d6cd4fb3f106559826e5b2d4830ebb47f454bd211e948abada5bd40bf7

        • C:\Users\Admin\Documents\MSDCSC\msdcsc.exe
          MD5

          c276255be8c317392e43735e0f707cf9

          SHA1

          8deb38349ef9978a83b8fee521de5e06d2b86052

          SHA256

          5fe7d9e94105fcb2dd524faee708442a10c98a98c9ea3b6ef35da17b6f7f4f47

          SHA512

          ebb335783435b6675751d9efaeb601874df6a21f41f9ac0877afc7ab19a5ef7287fa4f8fc81984396a6ff5e29c5a40449635745e3d51a254096d53398b2dd1a3

        • C:\Users\Admin\Documents\MSDCSC\msdcsc.exe
          MD5

          c276255be8c317392e43735e0f707cf9

          SHA1

          8deb38349ef9978a83b8fee521de5e06d2b86052

          SHA256

          5fe7d9e94105fcb2dd524faee708442a10c98a98c9ea3b6ef35da17b6f7f4f47

          SHA512

          ebb335783435b6675751d9efaeb601874df6a21f41f9ac0877afc7ab19a5ef7287fa4f8fc81984396a6ff5e29c5a40449635745e3d51a254096d53398b2dd1a3

        • memory/204-4-0x0000000000000000-mapping.dmp
        • memory/520-12-0x0000000000000000-mapping.dmp
        • memory/1012-10-0x0000000002820000-0x0000000002821000-memory.dmp
          Filesize

          4KB

        • memory/1012-11-0x0000000000000000-mapping.dmp
        • memory/1012-9-0x0000000000000000-mapping.dmp
        • memory/2224-15-0x0000000000000000-mapping.dmp
        • memory/2768-17-0x0000000000000000-mapping.dmp
        • memory/2768-18-0x0000000003110000-0x0000000003111000-memory.dmp
          Filesize

          4KB

        • memory/2768-19-0x0000000000000000-mapping.dmp
        • memory/2920-2-0x0000000000000000-mapping.dmp
        • memory/2940-7-0x0000000000000000-mapping.dmp
        • memory/3484-3-0x0000000000000000-mapping.dmp
        • memory/3944-6-0x0000000000000000-mapping.dmp