Analysis

  • max time kernel
    104s
  • max time network
    166s
  • platform
    windows7_x64
  • resource
    win7v20210408
  • submitted
    13/09/2021, 06:41

General

  • Target
    680f79b61eff2ac81b7fb13c3ccdf8323752b40c94d4d3a7a25bb776b2a08405.exe
  • Size 833KB
  • Sample210913-hfr2aagbbm
  • SHA256 680f79b61eff2ac81b7fb13c3ccdf8323752b40c94d4d3a7a25bb776b2a08405
  • MD5 SHA1 SHA512

Malware Config

Extracted

Family
  • vidar

Version
  • 40.5

Botnet
  • 517

C2
  • https://gheorghip.tumblr.com/

Attributes
  • profile_id

    517

Signatures

  • Detected Djvu ransomware 6 IoCs
  • Djvu Ransomware

    Ransomware which is a variant of the STOP family.

  • Vidar

    Vidar is an infostealer based on Arkei stealer.

  • suricata: ET MALWARE Potential Dridex.Maldoc Minimal Executable Request

    suricata: ET MALWARE Potential Dridex.Maldoc Minimal Executable Request

  • Vidar Stealer 4 IoCs
  • Downloads MZ/PE file
  • Executes dropped EXE 8 IoCs
  • Loads dropped DLL 8 IoCs
  • Modifies file permissions 1 TTPs 1 IoCs
  • Reads user/profile data of web browsers 2 TTPs

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

  • Accesses 2FA software files, possible credential harvesting 2 TTPs
  • Accesses cryptocurrency files/wallets, possible credential harvesting 2 TTPs
  • Adds Run key to start application 2 TTPs 1 IoCs
  • Checks installed software on the system 1 TTPs

    Looks up Uninstall key entries in the registry to enumerate software on the system.

  • Looks up external IP address via web service 3 IoCs

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

  • Suspicious use of SetThreadContext 6 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 2 IoCs

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

  • Delays execution with timeout.exe 1 IoCs
  • Kills process with taskkill 1 IoCs
  • Modifies system certificate store 2 TTPs 5 IoCs
  • Suspicious behavior: EnumeratesProcesses 8 IoCs
  • Suspicious use of AdjustPrivilegeToken 1 IoCs
  • Suspicious use of WriteProcessMemory 64 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\680f79b61eff2ac81b7fb13c3ccdf8323752b40c94d4d3a7a25bb776b2a08405.exe
    "C:\Users\Admin\AppData\Local\Temp\680f79b61eff2ac81b7fb13c3ccdf8323752b40c94d4d3a7a25bb776b2a08405.exe"
    1⤵
    • Suspicious use of SetThreadContext
    • Suspicious use of WriteProcessMemory
    PID:1104
    • C:\Users\Admin\AppData\Local\Temp\680f79b61eff2ac81b7fb13c3ccdf8323752b40c94d4d3a7a25bb776b2a08405.exe
      "C:\Users\Admin\AppData\Local\Temp\680f79b61eff2ac81b7fb13c3ccdf8323752b40c94d4d3a7a25bb776b2a08405.exe"
      2⤵
      • Adds Run key to start application
      • Modifies system certificate store
      • Suspicious behavior: EnumeratesProcesses
      • Suspicious use of WriteProcessMemory
      PID:1868
      • C:\Windows\SysWOW64\icacls.exe
        icacls "C:\Users\Admin\AppData\Local\793d02d0-e503-4445-a70a-20f176ccfd90" /deny *S-1-1-0:(OI)(CI)(DE,DC)
        3⤵
        • Modifies file permissions
        PID:1888
      • C:\Users\Admin\AppData\Local\Temp\680f79b61eff2ac81b7fb13c3ccdf8323752b40c94d4d3a7a25bb776b2a08405.exe
        "C:\Users\Admin\AppData\Local\Temp\680f79b61eff2ac81b7fb13c3ccdf8323752b40c94d4d3a7a25bb776b2a08405.exe" --Admin IsNotAutoStart IsNotTask
        3⤵
        • Suspicious use of SetThreadContext
        • Suspicious use of WriteProcessMemory
        PID:1752
        • C:\Users\Admin\AppData\Local\Temp\680f79b61eff2ac81b7fb13c3ccdf8323752b40c94d4d3a7a25bb776b2a08405.exe
          "C:\Users\Admin\AppData\Local\Temp\680f79b61eff2ac81b7fb13c3ccdf8323752b40c94d4d3a7a25bb776b2a08405.exe" --Admin IsNotAutoStart IsNotTask
          4⤵
          • Loads dropped DLL
          • Modifies system certificate store
          • Suspicious behavior: EnumeratesProcesses
          • Suspicious use of WriteProcessMemory
          PID:1648
          • C:\Users\Admin\AppData\Local\12a13aa5-e754-4aeb-a171-1291792de88b\build2.exe
            "C:\Users\Admin\AppData\Local\12a13aa5-e754-4aeb-a171-1291792de88b\build2.exe"
            5⤵
            • Executes dropped EXE
            • Suspicious use of SetThreadContext
            • Suspicious use of WriteProcessMemory
            PID:908
            • C:\Users\Admin\AppData\Local\12a13aa5-e754-4aeb-a171-1291792de88b\build2.exe
              "C:\Users\Admin\AppData\Local\12a13aa5-e754-4aeb-a171-1291792de88b\build2.exe"
              6⤵
              • Executes dropped EXE
              • Loads dropped DLL
              • Checks processor information in registry
              • Suspicious behavior: EnumeratesProcesses
              • Suspicious use of WriteProcessMemory
              PID:792
              • C:\Windows\SysWOW64\cmd.exe
                "C:\Windows\System32\cmd.exe" /c taskkill /im build2.exe /f & timeout /t 6 & del /f /q "C:\Users\Admin\AppData\Local\12a13aa5-e754-4aeb-a171-1291792de88b\build2.exe" & del C:\ProgramData\*.dll & exit
                7⤵
                  PID:1752
                  • C:\Windows\SysWOW64\taskkill.exe
                    taskkill /im build2.exe /f
                    8⤵
                    • Kills process with taskkill
                    • Suspicious use of AdjustPrivilegeToken
                    PID:1032
                  • C:\Windows\SysWOW64\timeout.exe
                    timeout /t 6
                    8⤵
                    • Delays execution with timeout.exe
                    PID:2028
            • C:\Users\Admin\AppData\Local\12a13aa5-e754-4aeb-a171-1291792de88b\build3.exe
              "C:\Users\Admin\AppData\Local\12a13aa5-e754-4aeb-a171-1291792de88b\build3.exe"
              5⤵
              • Executes dropped EXE
              • Suspicious use of SetThreadContext
              • Suspicious use of WriteProcessMemory
              PID:1536
              • C:\Users\Admin\AppData\Local\12a13aa5-e754-4aeb-a171-1291792de88b\build3.exe
                "C:\Users\Admin\AppData\Local\12a13aa5-e754-4aeb-a171-1291792de88b\build3.exe"
                6⤵
                • Executes dropped EXE
                • Suspicious use of WriteProcessMemory
                PID:1840
                • C:\Windows\SysWOW64\schtasks.exe
                  /C /create /F /sc minute /mo 1 /tn "Azure-Update-Task" /tr "C:\Users\Admin\AppData\Roaming\Microsoft\Network\mstsca.exe"
                  7⤵
                  • Creates scheduled task(s)
                  PID:1516
    • C:\Windows\system32\taskeng.exe
      taskeng.exe {25FB6E20-D283-4D91-8364-FD27C307429F} S-1-5-21-2455352368-1077083310-2879168483-1000:QWOCTUPM\Admin:Interactive:[1]
      1⤵
        PID:968
        • C:\Users\Admin\AppData\Roaming\Microsoft\Network\mstsca.exe
          C:\Users\Admin\AppData\Roaming\Microsoft\Network\mstsca.exe
          2⤵
          • Executes dropped EXE
          • Suspicious use of SetThreadContext
          PID:1664
          • C:\Users\Admin\AppData\Roaming\Microsoft\Network\mstsca.exe
            C:\Users\Admin\AppData\Roaming\Microsoft\Network\mstsca.exe
            3⤵
            • Executes dropped EXE
            PID:1680
            • C:\Windows\SysWOW64\schtasks.exe
              /C /create /F /sc minute /mo 1 /tn "Azure-Update-Task" /tr "C:\Users\Admin\AppData\Roaming\Microsoft\Network\mstsca.exe"
              4⤵
              • Creates scheduled task(s)
              PID:1332
        • C:\Users\Admin\AppData\Roaming\Microsoft\Network\mstsca.exe
          C:\Users\Admin\AppData\Roaming\Microsoft\Network\mstsca.exe
          2⤵
          • Executes dropped EXE
          • Suspicious use of SetThreadContext
          PID:828
          • C:\Users\Admin\AppData\Roaming\Microsoft\Network\mstsca.exe
            C:\Users\Admin\AppData\Roaming\Microsoft\Network\mstsca.exe
            3⤵
            • Executes dropped EXE
            PID:1172

      Network

            MITRE ATT&CK Enterprise v6

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            Downloads

            memory/792-83-0x0000000000400000-0x00000000004D5000-memory.dmp

            memory/792-88-0x0000000000400000-0x00000000004D5000-memory.dmp

            memory/908-87-0x00000000021D0000-0x00000000022A2000-memory.dmp

            memory/1104-62-0x0000000004440000-0x000000000455B000-memory.dmp

            memory/1536-98-0x0000000000220000-0x0000000000224000-memory.dmp

            memory/1648-77-0x0000000000400000-0x0000000000537000-memory.dmp

            memory/1840-99-0x0000000000400000-0x0000000000406000-memory.dmp

            memory/1840-94-0x0000000000400000-0x0000000000406000-memory.dmp

            memory/1868-63-0x0000000075551000-0x0000000075553000-memory.dmp

            memory/1868-60-0x0000000000400000-0x0000000000537000-memory.dmp

            memory/1868-64-0x0000000000400000-0x0000000000537000-memory.dmp