攻防世界 Reverse Mysterious

Mysterious
打开要输入password，随机输入123没有反应

拖进ida查看字符串

双击查看well done，交叉引用再反汇编，关键代码是几个if语句

if ( a2 == 16 )
  {
    DestroyWindow(hWnd);
    PostQuitMessage(0);
  }
  else if ( a2 == 273 )
  {
    if ( a3 == 1000 )
    {
      GetDlgItemTextA(hWnd, 1002, String, 260);//获取字符串
      strlen(String);
      if ( strlen(String) > 6 )//字符串长度要小于等于6
        ExitProcess(0);
      v4 = atoi(String);//字符串转整形
      Value = v4 + 1;//转成整形后再+1，也就是得到flag中会有123
      if ( v4 == 122 && String[3] == 120 && String[5] == 122 && String[4] == 121 ) //120,122,121转ASCII码分别为'x','y','z'
      {
        strcpy(Text, "flag");
        memset(v8, 0, sizeof(v8));
        v9 = 0;
        v10 = 0;
        _itoa(Value, Source, 10);
        strcat(Text, "{");
        strcat(Text, Source);
        strcat(Text, "_");
        strcat(Text, "Buff3r_0v3rf|0w");
        strcat(Text, "}");
        MessageBoxA(0, Text, "well done", 0);
      }
      SetTimer(hWnd, 1u, 0x3E8u, TimerFunc);
    }
    if ( a3 == 1001 )
      KillTimer(hWnd, 1u);
  }
  return 0;
}

分析后得到在程序中输入122xyz可以得到flag

标签：攻防,Reverse,Text,strcat,122,v4,hWnd,Mysterious,String
来源： https://blog.csdn.net/XFox_/article/details/119462142