Analysis

  • max time kernel
    149s
  • max time network
    145s
  • platform
    windows7_x64
  • resource
    win7-20230220-en
  • resource tags

    arch:x64arch:x86image:win7-20230220-enlocale:en-usos:windows7-x64system
  • submitted
    10-05-2023 01:36

General

  • Target

    7249a8d317ed6f5bd1e6374f602997ed.docx

  • Size

    10KB

  • MD5

    7249a8d317ed6f5bd1e6374f602997ed

  • SHA1

    5e9e5bb7cb643db46fcf86140a6705a7f23749ec

  • SHA256

    4c8ef08c0d896adae8f7f3012b7d7732e8e8950007ba8117a122440bcefcef8a

  • SHA512

    153b5042335f320a864e57ac30d049b2c5720c6c3d9e2e08d48da00234e335205971db711af2ca42e7ce0779ba81038fb2377f30a764de434ef14966cef885c0

  • SSDEEP

    192:ScIMmtPSi2EG/b/wLGbt0AOK1amWBXZVhhz03aHF:SPXST/0RAOeoJVh2al

Malware Config

Extracted

Family

remcos

Botnet

RemoteHost

C2

csc.mastercoa.co:55241

Attributes
  • audio_folder

    MicRecords

  • audio_record_time

    5

  • connect_delay

    0

  • connect_interval

    1

  • copy_file

    remcos.exe

  • copy_folder

    Remcos

  • delete_file

    false

  • hide_file

    false

  • hide_keylog_file

    false

  • install_flag

    false

  • keylog_crypt

    false

  • keylog_file

    logs.dat

  • keylog_flag

    false

  • keylog_folder

    remcos

  • mouse_option

    false

  • mutex

    Rmc-444WE8

  • screenshot_crypt

    false

  • screenshot_flag

    false

  • screenshot_folder

    Screenshots

  • screenshot_path

    %AppData%

  • screenshot_time

    10

  • startup_value

    Remcos

  • take_screenshot_option

    false

  • take_screenshot_time

    5

Signatures

  • Modifies WinLogon for persistence 2 TTPs 1 IoCs
  • Remcos

    Remcos is a closed-source remote control and surveillance software.

  • NirSoft MailPassView 3 IoCs

    Password recovery tool for various email clients

  • NirSoft WebBrowserPassView 3 IoCs

    Password recovery tool for various web browsers

  • Nirsoft 8 IoCs
  • Blocklisted process makes network request 1 IoCs
  • Downloads MZ/PE file
  • Abuses OpenXML format to download file from external location 2 IoCs
  • Executes dropped EXE 2 IoCs
  • Loads dropped DLL 2 IoCs
  • Uses the VBS compiler for execution 1 TTPs
  • Accesses Microsoft Outlook accounts 1 TTPs 1 IoCs
  • Suspicious use of SetThreadContext 4 IoCs
  • Drops file in Windows directory 1 IoCs
  • Office loads VBA resources, possible macro or embedded object present
  • Launches Equation Editor 1 TTPs 1 IoCs

    Equation Editor is an old Office component often targeted by exploits such as CVE-2017-11882.

  • Modifies Internet Explorer settings 1 TTPs 31 IoCs
  • Modifies registry class 64 IoCs
  • Runs ping.exe 1 TTPs 2 IoCs
  • Suspicious behavior: AddClipboardFormatListener 1 IoCs
  • Suspicious behavior: EnumeratesProcesses 64 IoCs
  • Suspicious behavior: MapViewOfSection 4 IoCs
  • Suspicious use of AdjustPrivilegeToken 3 IoCs
  • Suspicious use of SetWindowsHookEx 3 IoCs
  • Suspicious use of WriteProcessMemory 56 IoCs

Processes

  • C:\Program Files (x86)\Microsoft Office\Office14\WINWORD.EXE
    "C:\Program Files (x86)\Microsoft Office\Office14\WINWORD.EXE" /n "C:\Users\Admin\AppData\Local\Temp\7249a8d317ed6f5bd1e6374f602997ed.docx"
    1⤵
    • Abuses OpenXML format to download file from external location
    • Drops file in Windows directory
    • Modifies Internet Explorer settings
    • Modifies registry class
    • Suspicious behavior: AddClipboardFormatListener
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of SetWindowsHookEx
    • Suspicious use of WriteProcessMemory
    PID:1760
    • C:\Windows\splwow64.exe
      C:\Windows\splwow64.exe 12288
      2⤵
        PID:1860
    • C:\Program Files (x86)\Common Files\Microsoft Shared\EQUATION\EQNEDT32.EXE
      "C:\Program Files (x86)\Common Files\Microsoft Shared\EQUATION\EQNEDT32.EXE" -Embedding
      1⤵
      • Blocklisted process makes network request
      • Loads dropped DLL
      • Launches Equation Editor
      • Suspicious use of WriteProcessMemory
      PID:1692
      • C:\Users\Public\vbc.exe
        "C:\Users\Public\vbc.exe"
        2⤵
        • Executes dropped EXE
        • Suspicious use of SetThreadContext
        • Suspicious behavior: EnumeratesProcesses
        • Suspicious use of AdjustPrivilegeToken
        • Suspicious use of WriteProcessMemory
        PID:2044
        • C:\Windows\Microsoft.NET\Framework\v4.0.30319\AddInProcess32.exe
          "C:\Windows\Microsoft.NET\Framework\v4.0.30319\AddInProcess32.exe"
          3⤵
          • Loads dropped DLL
          • Suspicious use of SetThreadContext
          • Suspicious behavior: MapViewOfSection
          • Suspicious use of SetWindowsHookEx
          • Suspicious use of WriteProcessMemory
          PID:1572
          • C:\Windows\Microsoft.NET\Framework\v4.0.30319\AddInProcess32.exe
            C:\Windows\Microsoft.NET\Framework\v4.0.30319\AddInProcess32.exe /stext "C:\Users\Admin\AppData\Local\Temp\fvvmfei"
            4⤵
              PID:896
            • C:\Windows\Microsoft.NET\Framework\v4.0.30319\AddInProcess32.exe
              C:\Windows\Microsoft.NET\Framework\v4.0.30319\AddInProcess32.exe /stext "C:\Users\Admin\AppData\Local\Temp\qpafgwtjcly"
              4⤵
                PID:1888
              • C:\Windows\Microsoft.NET\Framework\v4.0.30319\AddInProcess32.exe
                C:\Windows\Microsoft.NET\Framework\v4.0.30319\AddInProcess32.exe /stext "C:\Users\Admin\AppData\Local\Temp\qpafgwtjcly"
                4⤵
                • Accesses Microsoft Outlook accounts
                PID:1780
              • C:\Windows\Microsoft.NET\Framework\v4.0.30319\AddInProcess32.exe
                C:\Windows\Microsoft.NET\Framework\v4.0.30319\AddInProcess32.exe /stext "C:\Users\Admin\AppData\Local\Temp\srfpypelqtqegv"
                4⤵
                • Suspicious use of AdjustPrivilegeToken
                PID:1020
              • C:\Users\Admin\AppData\Local\Temp\20ok.exe
                "C:\Users\Admin\AppData\Local\Temp\20ok.exe"
                4⤵
                • Executes dropped EXE
                PID:1984
                • C:\Windows\SysWOW64\cmd.exe
                  "cmd" /c ping 127.0.0.1 -n 36 > nul && REG ADD "HKCU\Software\Microsoft\Windows NT\CurrentVersion\Winlogon" /f /v "Shell" /t REG_SZ /d "explorer.exe,C:\Users\Admin\AppData\Roaming\fdhfggmmsn\sfghdjdfvbniop8t.exe,"
                  5⤵
                  • Suspicious use of WriteProcessMemory
                  PID:1104
                  • C:\Windows\SysWOW64\PING.EXE
                    ping 127.0.0.1 -n 36
                    6⤵
                    • Runs ping.exe
                    PID:1492
                  • C:\Windows\SysWOW64\reg.exe
                    REG ADD "HKCU\Software\Microsoft\Windows NT\CurrentVersion\Winlogon" /f /v "Shell" /t REG_SZ /d "explorer.exe,C:\Users\Admin\AppData\Roaming\fdhfggmmsn\sfghdjdfvbniop8t.exe,"
                    6⤵
                    • Modifies WinLogon for persistence
                    PID:1672
                • C:\Windows\SysWOW64\cmd.exe
                  "cmd" /c ping 127.0.0.1 -n 49 > nul && copy "C:\Users\Admin\AppData\Local\Temp\20ok.exe" "C:\Users\Admin\AppData\Roaming\fdhfggmmsn\sfghdjdfvbniop8t.exe" && ping 127.0.0.1 -n 49 > nul && "C:\Users\Admin\AppData\Roaming\fdhfggmmsn\sfghdjdfvbniop8t.exe"
                  5⤵
                  • Suspicious use of WriteProcessMemory
                  PID:664
                  • C:\Windows\SysWOW64\PING.EXE
                    ping 127.0.0.1 -n 49
                    6⤵
                    • Runs ping.exe
                    PID:808

        Network

        MITRE ATT&CK Matrix ATT&CK v6

        Execution

        Scripting

        1
        T1064

        Exploitation for Client Execution

        1
        T1203

        Persistence

        Winlogon Helper DLL

        1
        T1004

        Defense Evasion

        Modify Registry

        2
        T1112

        Scripting

        1
        T1064

        Discovery

        Remote System Discovery

        1
        T1018

        Collection

        Email Collection

        1
        T1114

        Replay Monitor

        Loading Replay Monitor...

        Downloads

        • C:\ProgramData\remcos\logs.dat
          Filesize

          320B

          MD5

          9a78e64ed4ec802ac092665ff4d983fc

          SHA1

          7d8c158e9e5d7ede81865809056f1405be441467

          SHA256

          19c33ee8d67a7e4ed9d639f20bb5a1f44e5e30beaaf77e4ff45887894ea711f4

          SHA512

          2f592e376ff8a310f1db7f42dc6000e5217403e428c3171651bbcfb18f00d7f6d19d6b95e8149110864ff9cd1e78812ac3be3d8f6e7d4c41141348810a6fa033

        • C:\Users\Admin\AppData\Local\Microsoft\Office\14.0\OfficeFileCache\LocalCacheFileEditManager\FSD-CNRY.FSD
          Filesize

          128KB

          MD5

          1d74ff0a8f40adf5fcd946cce16952b1

          SHA1

          2618b8be4108b038698a7b7712c1e966dd3c825d

          SHA256

          a84f0cd9167392b23d88df4e7f5ea76840dbdb16f953e671214df5ceda912567

          SHA512

          11045e082fe181422f4532450933a3a7fc0a46604a0c4d360a534e8cbaedfa4f5d18f5181940f49bd2423acc7d25fc8de71158dc7a082cb7b55749d0a00d2366

        • C:\Users\Admin\AppData\Local\Microsoft\Office\14.0\OfficeFileCache\LocalCacheFileEditManager\FSD-{4F69F92E-AAD9-4096-B639-C8D0CEA4312C}.FSD
          Filesize

          128KB

          MD5

          809cd3eea658076d3a2c08613b226716

          SHA1

          da933e552c2b7fc19bbadab35127003860d0f3cd

          SHA256

          414f355f988b3ae58a2aa79451c9d05181d63c2ab37cd5535523f97c09fea6b7

          SHA512

          188af3adf330a23ab58043ef364128db5966782cff35560b4aa062293e4bcddd25e440022c4fa66d9890a9cf6a255e2fc82c83e08077332f7d868d9ca237975b

        • C:\Users\Admin\AppData\Local\Microsoft\Windows\Temporary Internet Files\Content.IE5\S7FIT0B8\##############################################[1].doc
          Filesize

          22KB

          MD5

          54e110633d9eab07a128d77a2983d306

          SHA1

          ed8ad3d9cf7941cd3d3f5c585ba534dbe050a5af

          SHA256

          904be1f7a689b97de339c54ded763b7dc26acb941fee56e585aa9e6350f65f17

          SHA512

          771dd723f00d96910548a0d4a39a89914dc118ae6e4859373993bd6f117e9db191b477660a6898b05a9d9fe8d1d959fe712f53b6869dcfaeced9206950d32c93

        • C:\Users\Admin\AppData\Local\Temp\20ok.exe
          Filesize

          1.8MB

          MD5

          611e1fc8100044d0c7b4e8c194fe7cee

          SHA1

          a5131201b03969e007928fc21a3465c149824569

          SHA256

          77849aab387e345adfe8564247e7e8a44b00991a748387054ac6c534880cdfb1

          SHA512

          05044d8f0fe25bd1d14ef03c9b0efce2e2478cc2910c9c15ee6088fdf50c47ad353339a6abb4dbf4210f202cc50bb5c5cf6deb6ee5ca87211a6b4524fb200cce

        • C:\Users\Admin\AppData\Local\Temp\fvvmfei
          Filesize

          2B

          MD5

          f3b25701fe362ec84616a93a45ce9998

          SHA1

          d62636d8caec13f04e28442a0a6fa1afeb024bbb

          SHA256

          b3d510ef04275ca8e698e5b3cbb0ece3949ef9252f0cdc839e9ee347409a2209

          SHA512

          98c5f56f3de340690c139e58eb7dac111979f0d4dffe9c4b24ff849510f4b6ffa9fd608c0a3de9ac3c9fd2190f0efaf715309061490f9755a9bfdf1c54ca0d84

        • C:\Users\Admin\AppData\Local\Temp\fvvmfei
          Filesize

          2B

          MD5

          f3b25701fe362ec84616a93a45ce9998

          SHA1

          d62636d8caec13f04e28442a0a6fa1afeb024bbb

          SHA256

          b3d510ef04275ca8e698e5b3cbb0ece3949ef9252f0cdc839e9ee347409a2209

          SHA512

          98c5f56f3de340690c139e58eb7dac111979f0d4dffe9c4b24ff849510f4b6ffa9fd608c0a3de9ac3c9fd2190f0efaf715309061490f9755a9bfdf1c54ca0d84

        • C:\Users\Admin\AppData\Local\Temp\{4A5F7A84-D80E-44D2-9459-E97E2BBD0286}
          Filesize

          128KB

          MD5

          75bc3d3af2b0162d618da5600f724e73

          SHA1

          e876608db5486cd8424533ea4fb5ca3d92c83dbc

          SHA256

          e77043b12f164c2b92e56b664b0e11ca4c89cb77207b3ff3f8ee42591d08bc11

          SHA512

          66f412338e3fb0141ba7e03d81957bb8f4fbd5652ef5205b12032640eefc4f4c2e7c238fa6a130bd26e9fb1f75df71d58b12aae20d80cfd290bc094b095a4a22

        • C:\Users\Admin\AppData\Roaming\Microsoft\Templates\Normal.dotm
          Filesize

          20KB

          MD5

          e3e75650a67fd858ef2e06349bf6506f

          SHA1

          82b29e1146cf3f67566c5cd1cf14575760a7f0e4

          SHA256

          98092332b3ed6f6ecf0981b5816fe560224a1e52c50e864863992b17d28d64fe

          SHA512

          534defd166f643eaad470ca9e4e71b2dad2fe7117e3f4b0fe005191dca0a5019e8fb991de6c8f382cf122043cf8a92008184fb2900eb7ddab1b152c74dda28f1

        • C:\Users\Public\vbc.exe
          Filesize

          2.4MB

          MD5

          2c3948b46ad3f0972c57d86e00fe3ef0

          SHA1

          81cba7a7dd95391c34453f3dcf46639d273522b7

          SHA256

          a90db92cdebc3d71dfae9a9dfe1447b629db2724fd093d22e8f53e7aeab26a74

          SHA512

          10eabc8112c86ee850990ad21eb27e26f98914dfa71bf6ba744a1e1aa5cc74b82054ded9089070d2501f798cb03da25be3b531af3fa3af6b00927c19867f0601

        • C:\Users\Public\vbc.exe
          Filesize

          2.4MB

          MD5

          2c3948b46ad3f0972c57d86e00fe3ef0

          SHA1

          81cba7a7dd95391c34453f3dcf46639d273522b7

          SHA256

          a90db92cdebc3d71dfae9a9dfe1447b629db2724fd093d22e8f53e7aeab26a74

          SHA512

          10eabc8112c86ee850990ad21eb27e26f98914dfa71bf6ba744a1e1aa5cc74b82054ded9089070d2501f798cb03da25be3b531af3fa3af6b00927c19867f0601

        • C:\Users\Public\vbc.exe
          Filesize

          2.4MB

          MD5

          2c3948b46ad3f0972c57d86e00fe3ef0

          SHA1

          81cba7a7dd95391c34453f3dcf46639d273522b7

          SHA256

          a90db92cdebc3d71dfae9a9dfe1447b629db2724fd093d22e8f53e7aeab26a74

          SHA512

          10eabc8112c86ee850990ad21eb27e26f98914dfa71bf6ba744a1e1aa5cc74b82054ded9089070d2501f798cb03da25be3b531af3fa3af6b00927c19867f0601

        • \Users\Admin\AppData\Local\Temp\20ok.exe
          Filesize

          1.8MB

          MD5

          611e1fc8100044d0c7b4e8c194fe7cee

          SHA1

          a5131201b03969e007928fc21a3465c149824569

          SHA256

          77849aab387e345adfe8564247e7e8a44b00991a748387054ac6c534880cdfb1

          SHA512

          05044d8f0fe25bd1d14ef03c9b0efce2e2478cc2910c9c15ee6088fdf50c47ad353339a6abb4dbf4210f202cc50bb5c5cf6deb6ee5ca87211a6b4524fb200cce

        • \Users\Public\vbc.exe
          Filesize

          2.4MB

          MD5

          2c3948b46ad3f0972c57d86e00fe3ef0

          SHA1

          81cba7a7dd95391c34453f3dcf46639d273522b7

          SHA256

          a90db92cdebc3d71dfae9a9dfe1447b629db2724fd093d22e8f53e7aeab26a74

          SHA512

          10eabc8112c86ee850990ad21eb27e26f98914dfa71bf6ba744a1e1aa5cc74b82054ded9089070d2501f798cb03da25be3b531af3fa3af6b00927c19867f0601

        • memory/896-206-0x0000000000400000-0x0000000000478000-memory.dmp
          Filesize

          480KB

        • memory/896-185-0x0000000000400000-0x0000000000478000-memory.dmp
          Filesize

          480KB

        • memory/896-200-0x0000000000400000-0x0000000000478000-memory.dmp
          Filesize

          480KB

        • memory/896-194-0x0000000000400000-0x0000000000478000-memory.dmp
          Filesize

          480KB

        • memory/896-188-0x0000000000400000-0x0000000000478000-memory.dmp
          Filesize

          480KB

        • memory/1020-199-0x0000000000400000-0x0000000000424000-memory.dmp
          Filesize

          144KB

        • memory/1020-198-0x0000000000400000-0x0000000000424000-memory.dmp
          Filesize

          144KB

        • memory/1020-197-0x0000000000400000-0x0000000000424000-memory.dmp
          Filesize

          144KB

        • memory/1020-192-0x0000000000400000-0x0000000000424000-memory.dmp
          Filesize

          144KB

        • memory/1572-156-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-215-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-164-0x000000007EFDE000-0x000000007EFDF000-memory.dmp
          Filesize

          4KB

        • memory/1572-162-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-287-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-286-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-167-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-168-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-169-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-171-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-172-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-173-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-174-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-175-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-176-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-177-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-178-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-182-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-183-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-161-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-267-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-160-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-266-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-222-0x0000000010000000-0x0000000010019000-memory.dmp
          Filesize

          100KB

        • memory/1572-159-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-221-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-157-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-220-0x0000000010000000-0x0000000010019000-memory.dmp
          Filesize

          100KB

        • memory/1572-217-0x0000000010000000-0x0000000010019000-memory.dmp
          Filesize

          100KB

        • memory/1572-155-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1572-163-0x0000000000400000-0x0000000000480000-memory.dmp
          Filesize

          512KB

        • memory/1760-54-0x000000005FFF0000-0x0000000060000000-memory.dmp
          Filesize

          64KB

        • memory/1760-257-0x000000005FFF0000-0x0000000060000000-memory.dmp
          Filesize

          64KB

        • memory/1780-187-0x000000007EFDE000-0x000000007EFDF000-memory.dmp
          Filesize

          4KB

        • memory/1780-189-0x0000000000400000-0x0000000000457000-memory.dmp
          Filesize

          348KB

        • memory/1780-201-0x0000000000400000-0x0000000000457000-memory.dmp
          Filesize

          348KB

        • memory/1780-196-0x0000000000400000-0x0000000000457000-memory.dmp
          Filesize

          348KB

        • memory/1780-193-0x0000000000400000-0x0000000000457000-memory.dmp
          Filesize

          348KB

        • memory/1780-216-0x0000000000400000-0x0000000000457000-memory.dmp
          Filesize

          348KB

        • memory/2044-146-0x0000000000260000-0x0000000000278000-memory.dmp
          Filesize

          96KB

        • memory/2044-158-0x00000000058A0000-0x00000000058E0000-memory.dmp
          Filesize

          256KB

        • memory/2044-154-0x0000000000320000-0x0000000000326000-memory.dmp
          Filesize

          24KB

        • memory/2044-145-0x00000000002C0000-0x000000000030A000-memory.dmp
          Filesize

          296KB

        • memory/2044-143-0x00000000058A0000-0x00000000058E0000-memory.dmp
          Filesize

          256KB

        • memory/2044-147-0x00000000058A0000-0x00000000058E0000-memory.dmp
          Filesize

          256KB

        • memory/2044-142-0x0000000001210000-0x0000000001472000-memory.dmp
          Filesize

          2.4MB

        • memory/2044-152-0x00000000058A0000-0x00000000058E0000-memory.dmp
          Filesize

          256KB

        • memory/2044-153-0x0000000000550000-0x000000000056A000-memory.dmp
          Filesize

          104KB

        • memory/2044-166-0x00000000058A0000-0x00000000058E0000-memory.dmp
          Filesize

          256KB

        • memory/2044-165-0x00000000058A0000-0x00000000058E0000-memory.dmp
          Filesize

          256KB