Analysis

  • max time kernel
    152s
  • max time network
    152s
  • platform
    windows7_x64
  • resource
    win7-en-20211208
  • submitted
    08/12/2021, 15:47

General

  • Target

    mrkbajwnyr.txt.jar

  • Size

    185KB

  • MD5

    4a769959e2ee2785d32ef2161f28cd8b

  • SHA1

    e31b455b90081313e3b7405db3efe1582fe39daa

  • SHA256

    496536d34981fc4155772fe136930ef13cf16116a4df18e6261dd084fce40b21

  • SHA512

    8ef798581834a365f8a7649572c8683e9294cb950917b9c1e9b6ae60bf48b2e4d0e3be312843e398868f31835f276df24f4c5c2b6fb07b654322a8d5351815ca

Malware Config

Signatures

  • STRRAT

    STRRAT is a remote access tool than can steal credentials and log keystrokes.

  • suricata: ET MALWARE STRRAT CnC Checkin

    suricata: ET MALWARE STRRAT CnC Checkin

  • Drops startup file 1 IoCs
  • Loads dropped DLL 2 IoCs
  • Adds Run key to start application 2 TTPs 2 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.

  • Creates scheduled task(s) 1 TTPs 1 IoCs

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

  • Suspicious use of AdjustPrivilegeToken 64 IoCs
  • Suspicious use of WriteProcessMemory 36 IoCs

Processes

  • C:\Windows\system32\java.exe
    java -jar C:\Users\Admin\AppData\Local\Temp\mrkbajwnyr.txt.jar
    1⤵
    • Suspicious use of WriteProcessMemory
    PID:1668
    • C:\Program Files\Java\jre7\bin\java.exe
      "C:\Program Files\Java\jre7\bin\java.exe" -jar "C:\Users\Admin\mrkbajwnyr.txt.jar"
      2⤵
      • Drops startup file
      • Loads dropped DLL
      • Adds Run key to start application
      • Suspicious use of WriteProcessMemory
      PID:1732
      • C:\Windows\system32\cmd.exe
        cmd /c schtasks /create /sc minute /mo 30 /tn Skype /tr "C:\Users\Admin\AppData\Roaming\mrkbajwnyr.txt.jar"
        3⤵
        • Suspicious use of WriteProcessMemory
        PID:1968
        • C:\Windows\system32\schtasks.exe
          schtasks /create /sc minute /mo 30 /tn Skype /tr "C:\Users\Admin\AppData\Roaming\mrkbajwnyr.txt.jar"
          4⤵
          • Creates scheduled task(s)
          PID:1740
      • C:\Program Files\Java\jre7\bin\java.exe
        "C:\Program Files\Java\jre7\bin\java.exe" -jar "C:\Users\Admin\AppData\Roaming\mrkbajwnyr.txt.jar"
        3⤵
        • Loads dropped DLL
        • Suspicious use of WriteProcessMemory
        PID:1016
        • C:\Windows\system32\cmd.exe
          cmd.exe /c "wmic /node:. /namespace:'\\root\cimv2' path win32_logicaldisk get volumeserialnumber /format:list"
          4⤵
          • Suspicious use of WriteProcessMemory
          PID:1212
          • C:\Windows\System32\Wbem\WMIC.exe
            wmic /node:. /namespace:'\\root\cimv2' path win32_logicaldisk get volumeserialnumber /format:list
            5⤵
            • Suspicious use of AdjustPrivilegeToken
            PID:1220
        • C:\Windows\system32\cmd.exe
          cmd.exe /c "wmic /node:. /namespace:'\\root\cimv2' path win32_operatingsystem get caption,OSArchitecture /format:list"
          4⤵
          • Suspicious use of WriteProcessMemory
          PID:336
          • C:\Windows\System32\Wbem\WMIC.exe
            wmic /node:. /namespace:'\\root\cimv2' path win32_operatingsystem get caption,OSArchitecture /format:list
            5⤵
            • Suspicious use of AdjustPrivilegeToken
            PID:376
        • C:\Windows\system32\cmd.exe
          cmd.exe /c "wmic /node:. /namespace:'\\root\cimv2' path win32_operatingsystem get version /format:list"
          4⤵
          • Suspicious use of WriteProcessMemory
          PID:1104
          • C:\Windows\System32\Wbem\WMIC.exe
            wmic /node:. /namespace:'\\root\cimv2' path win32_operatingsystem get version /format:list
            5⤵
              PID:572
          • C:\Windows\system32\cmd.exe
            cmd.exe /c "wmic /node:localhost /namespace:'\\root\securitycenter' path antivirusproduct get displayname /format:list"
            4⤵
            • Suspicious use of WriteProcessMemory
            PID:768
            • C:\Windows\System32\Wbem\WMIC.exe
              wmic /node:localhost /namespace:'\\root\securitycenter' path antivirusproduct get displayname /format:list
              5⤵
                PID:1556

      Network

            MITRE ATT&CK Enterprise v6

            Replay Monitor

            Loading Replay Monitor...

            Downloads

            • memory/1016-139-0x0000000002110000-0x0000000002380000-memory.dmp

              Filesize

              2.4MB

            • memory/1668-72-0x0000000000230000-0x0000000000231000-memory.dmp

              Filesize

              4KB

            • memory/1668-113-0x0000000000230000-0x0000000000231000-memory.dmp

              Filesize

              4KB

            • memory/1668-101-0x0000000000230000-0x0000000000231000-memory.dmp

              Filesize

              4KB

            • memory/1668-77-0x0000000000230000-0x0000000000231000-memory.dmp

              Filesize

              4KB

            • memory/1668-55-0x000007FEFC3A1000-0x000007FEFC3A3000-memory.dmp

              Filesize

              8KB

            • memory/1668-107-0x0000000000230000-0x0000000000231000-memory.dmp

              Filesize

              4KB

            • memory/1668-56-0x0000000002250000-0x00000000024C0000-memory.dmp

              Filesize

              2.4MB

            • memory/1668-108-0x0000000000230000-0x0000000000231000-memory.dmp

              Filesize

              4KB

            • memory/1668-109-0x0000000000230000-0x0000000000231000-memory.dmp

              Filesize

              4KB

            • memory/1668-71-0x0000000000230000-0x0000000000231000-memory.dmp

              Filesize

              4KB

            • memory/1668-110-0x0000000000230000-0x0000000000231000-memory.dmp

              Filesize

              4KB

            • memory/1668-70-0x0000000000230000-0x0000000000231000-memory.dmp

              Filesize

              4KB

            • memory/1668-59-0x0000000000230000-0x0000000000231000-memory.dmp

              Filesize

              4KB

            • memory/1668-58-0x0000000000230000-0x0000000000231000-memory.dmp

              Filesize

              4KB

            • memory/1668-57-0x0000000002250000-0x00000000024C0000-memory.dmp

              Filesize

              2.4MB

            • memory/1668-117-0x0000000000230000-0x0000000000231000-memory.dmp

              Filesize

              4KB

            • memory/1668-111-0x0000000000230000-0x0000000000231000-memory.dmp

              Filesize

              4KB

            • memory/1668-115-0x0000000000230000-0x0000000000231000-memory.dmp

              Filesize

              4KB

            • memory/1668-114-0x0000000000230000-0x0000000000231000-memory.dmp

              Filesize

              4KB

            • memory/1668-106-0x0000000000230000-0x0000000000231000-memory.dmp

              Filesize

              4KB

            • memory/1732-121-0x0000000000220000-0x0000000000221000-memory.dmp

              Filesize

              4KB

            • memory/1732-122-0x0000000002100000-0x0000000002370000-memory.dmp

              Filesize

              2.4MB