Analysis

  • max time kernel
    65s
  • max time network
    117s
  • platform
    windows7_x64
  • resource
    win7-20230220-en
  • resource tags

    arch:x64arch:x86image:win7-20230220-enlocale:en-usos:windows7-x64system
  • submitted
    13-05-2023 22:48

General

  • Target

    build4.exe

  • Size

    165KB

  • MD5

    547933c1a8ea0eb111e619d70ca2c657

  • SHA1

    aca394a095c3951ace115ac621a67df1ff4d2e33

  • SHA256

    fdc83f58a30b80240c5887c6646324600f3896421059b80caddacfdb196287ea

  • SHA512

    5df1b41c5f19e304cc0758b175252c17cc6ccb1d3d91ba2f153138dfbd8e2ef3cd6efe8a136559c55952bdb43a7f206f7ba4e04674ee95363ca8409e48745c2b

  • SSDEEP

    1536:ROwwIJbzij3pPEOGFmd8Szav8IDYFUxT1DR5jPVSBSVG41AG9wL4yXacCwPIC6Xi:RyIlz2p8Yai3GNzDeeb4FzeDGwKSHqj

Score
10/10

Malware Config

Extracted

Family

gurcu

C2

https://api.telegram.org/bot6193093056:AAHzyNGUGS9aUG6CCx6ENLoXpCFLzEQywIQ/sendMessage?chat_id=1098292643

Signatures

  • Gurcu, WhiteSnake

    Gurcu is a malware stealer written in C#.

  • Deletes itself 1 IoCs
  • Executes dropped EXE 2 IoCs
  • Reads user/profile data of web browsers 2 TTPs

    Infostealers often target stored browser data, which can include saved credentials etc.

  • Looks up external IP address via web service 1 IoCs

    Uses a legitimate IP lookup service to find the infected system's external IP.

  • Enumerates physical storage devices 1 TTPs

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

  • Program crash 2 IoCs
  • Creates scheduled task(s) 1 TTPs 1 IoCs

    Schtasks is often used by malware for persistence or to perform post-infection execution.

  • Modifies system certificate store 2 TTPs 6 IoCs
  • Runs ping.exe 1 TTPs 1 IoCs
  • Suspicious use of AdjustPrivilegeToken 2 IoCs
  • Suspicious use of WriteProcessMemory 24 IoCs
  • Uses Task Scheduler COM API 1 TTPs

    The Task Scheduler COM API can be used to schedule applications to run on boot or at set times.

Processes

  • C:\Users\Admin\AppData\Local\Temp\build4.exe
    "C:\Users\Admin\AppData\Local\Temp\build4.exe"
    1⤵
    • Suspicious use of WriteProcessMemory
    PID:1376
    • C:\Windows\System32\cmd.exe
      "C:\Windows\System32\cmd.exe" /C chcp 65001 && ping 127.0.0.1 && schtasks /create /tn "build4" /sc MINUTE /tr "C:\Users\Admin\AppData\Local\NET.Framework\build4.exe" /rl HIGHEST /f && DEL /F /S /Q /A "C:\Users\Admin\AppData\Local\Temp\build4.exe" &&START "" "C:\Users\Admin\AppData\Local\NET.Framework\build4.exe"
      2⤵
      • Deletes itself
      • Suspicious use of WriteProcessMemory
      PID:1888
      • C:\Windows\system32\chcp.com
        chcp 65001
        3⤵
          PID:1476
        • C:\Windows\system32\PING.EXE
          ping 127.0.0.1
          3⤵
          • Runs ping.exe
          PID:1484
        • C:\Windows\system32\schtasks.exe
          schtasks /create /tn "build4" /sc MINUTE /tr "C:\Users\Admin\AppData\Local\NET.Framework\build4.exe" /rl HIGHEST /f
          3⤵
          • Creates scheduled task(s)
          PID:520
        • C:\Users\Admin\AppData\Local\NET.Framework\build4.exe
          "C:\Users\Admin\AppData\Local\NET.Framework\build4.exe"
          3⤵
          • Executes dropped EXE
          • Modifies system certificate store
          • Suspicious use of AdjustPrivilegeToken
          • Suspicious use of WriteProcessMemory
          PID:340
          • C:\Windows\system32\WerFault.exe
            C:\Windows\system32\WerFault.exe -u -p 340 -s 1616
            4⤵
            • Program crash
            PID:544
    • C:\Windows\system32\taskeng.exe
      taskeng.exe {E27A80E2-1632-4F4D-A8E7-B2DD30353251} S-1-5-21-3948302646-268491222-1934009652-1000:KXZDHPUW\Admin:Interactive:[1]
      1⤵
      • Suspicious use of WriteProcessMemory
      PID:1468
      • C:\Users\Admin\AppData\Local\NET.Framework\build4.exe
        C:\Users\Admin\AppData\Local\NET.Framework\build4.exe
        2⤵
        • Executes dropped EXE
        • Suspicious use of AdjustPrivilegeToken
        • Suspicious use of WriteProcessMemory
        PID:664
        • C:\Windows\system32\WerFault.exe
          C:\Windows\system32\WerFault.exe -u -p 664 -s 1808
          3⤵
          • Program crash
          PID:1552

    Network

    MITRE ATT&CK Enterprise v6

    Replay Monitor

    Loading Replay Monitor...

    Downloads

    • C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\Content\94308059B57B3142E455B38A6EB92015

      Filesize

      62KB

      MD5

      3ac860860707baaf32469fa7cc7c0192

      SHA1

      c33c2acdaba0e6fa41fd2f00f186804722477639

      SHA256

      d015145d551ecd14916270efad773bbc9fd57fad2228d2c24559f696c961d904

      SHA512

      d62ad2408c969a95550fb87efda50f988770ba5e39972041bf85924275baf156b8bec309ecc6409e5acdd37ec175dea40eff921ab58933b5b5b5d35a6147567c

    • C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\Content\94308059B57B3142E455B38A6EB92015

      Filesize

      62KB

      MD5

      3ac860860707baaf32469fa7cc7c0192

      SHA1

      c33c2acdaba0e6fa41fd2f00f186804722477639

      SHA256

      d015145d551ecd14916270efad773bbc9fd57fad2228d2c24559f696c961d904

      SHA512

      d62ad2408c969a95550fb87efda50f988770ba5e39972041bf85924275baf156b8bec309ecc6409e5acdd37ec175dea40eff921ab58933b5b5b5d35a6147567c

    • C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015

      Filesize

      304B

      MD5

      4b5d4791938249f7c21c6bcb3f65e0e9

      SHA1

      129b0a60eae8f8a20caec221a85a372a11d886a8

      SHA256

      65f3a0d5fbbd854991f6116d43c18abd67515f6cfcd9106ae926c14a8b26f95e

      SHA512

      5d57489a2c3f8c18be9baef099a03b8347422b2fe069d2b2a74c2552a434b4a70d9b1c290ff39f1abf6b8c6326b438f46480fc1c046062d274520026d259414d

    • C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015

      Filesize

      304B

      MD5

      bfdce064e6c219e6824ae0ad3d72803f

      SHA1

      b976a8048935eb1d24c36d22cdfd636357cc5482

      SHA256

      a9357fd7de95a3a6490a111ae888b3544b8f49367a9de1755305b51b98019723

      SHA512

      fa020f7f8460885af9f04fe0483507e175c9dbda163e9c9c03b05aa6423d24caffe4caf9aab02ffc8c1d2a3687ccfa16647038190bb5b987a4ee0ff600526966

    • C:\Users\Admin\AppData\Local\NET.Framework\build4.exe

      Filesize

      165KB

      MD5

      547933c1a8ea0eb111e619d70ca2c657

      SHA1

      aca394a095c3951ace115ac621a67df1ff4d2e33

      SHA256

      fdc83f58a30b80240c5887c6646324600f3896421059b80caddacfdb196287ea

      SHA512

      5df1b41c5f19e304cc0758b175252c17cc6ccb1d3d91ba2f153138dfbd8e2ef3cd6efe8a136559c55952bdb43a7f206f7ba4e04674ee95363ca8409e48745c2b

    • C:\Users\Admin\AppData\Local\NET.Framework\build4.exe

      Filesize

      165KB

      MD5

      547933c1a8ea0eb111e619d70ca2c657

      SHA1

      aca394a095c3951ace115ac621a67df1ff4d2e33

      SHA256

      fdc83f58a30b80240c5887c6646324600f3896421059b80caddacfdb196287ea

      SHA512

      5df1b41c5f19e304cc0758b175252c17cc6ccb1d3d91ba2f153138dfbd8e2ef3cd6efe8a136559c55952bdb43a7f206f7ba4e04674ee95363ca8409e48745c2b

    • C:\Users\Admin\AppData\Local\NET.Framework\build4.exe

      Filesize

      165KB

      MD5

      547933c1a8ea0eb111e619d70ca2c657

      SHA1

      aca394a095c3951ace115ac621a67df1ff4d2e33

      SHA256

      fdc83f58a30b80240c5887c6646324600f3896421059b80caddacfdb196287ea

      SHA512

      5df1b41c5f19e304cc0758b175252c17cc6ccb1d3d91ba2f153138dfbd8e2ef3cd6efe8a136559c55952bdb43a7f206f7ba4e04674ee95363ca8409e48745c2b

    • C:\Users\Admin\AppData\Local\Temp\Cab480C.tmp

      Filesize

      61KB

      MD5

      fc4666cbca561e864e7fdf883a9e6661

      SHA1

      2f8d6094c7a34bf12ea0bbf0d51ee9c5bb7939a5

      SHA256

      10f3deb6c452d749a7451b5d065f4c0449737e5ee8a44f4d15844b503141e65b

      SHA512

      c71f54b571e01f247f072be4bbebdf5d8410b67eb79a61e7e0d9853fe857ab9bd12f53e6af3394b935560178107291fc4be351b27deb388eba90ba949633d57d

    • C:\Users\Admin\AppData\Local\Temp\Tar48ED.tmp

      Filesize

      164KB

      MD5

      4ff65ad929cd9a367680e0e5b1c08166

      SHA1

      c0af0d4396bd1f15c45f39d3b849ba444233b3a2

      SHA256

      c8733c93cc5aaf5ca206d06af22ee8dbdec764fb5085019a6a9181feb9dfdee6

      SHA512

      f530dc0d024a5a3b8903ffaaa41b608a5ccdd6da4ba1949f2c2e55a9fca475fec5c8d2119b5763cabe7ef1c3788fb9dcac621869db51d65b1d83cfe404fb4c27

    • C:\Users\Admin\AppData\Local\d92pmiifqt\port.dat

      Filesize

      4B

      MD5

      49d4b2faeb4b7b9e745775793141e2b2

      SHA1

      3dae524e50058ba5db59f21a1e88a4afb176c122

      SHA256

      b0b03d744a85f4459c71437fe196dd925a299a06ae7a425615c903c97c36b8fb

      SHA512

      55d648b97149a610c92bd881b5f99e0dcb6fa5bab48de9184dbda98cab5a8d33c4e5c91b2fffbe5da8f404db0d65b840a868d63a8403a584a5b721086b52f821

    • memory/340-131-0x000000001B030000-0x000000001B0B0000-memory.dmp

      Filesize

      512KB

    • memory/340-63-0x000000001B030000-0x000000001B0B0000-memory.dmp

      Filesize

      512KB

    • memory/340-61-0x00000000001A0000-0x00000000001D0000-memory.dmp

      Filesize

      192KB

    • memory/664-134-0x0000000000690000-0x0000000000710000-memory.dmp

      Filesize

      512KB

    • memory/664-154-0x0000000000690000-0x0000000000710000-memory.dmp

      Filesize

      512KB

    • memory/1376-54-0x0000000000BB0000-0x0000000000BE0000-memory.dmp

      Filesize

      192KB

    • memory/1376-57-0x000000001B140000-0x000000001B1C0000-memory.dmp

      Filesize

      512KB