# 枯燥的抽奖

接口请求了check.php

写脚本：

```
<?php

mt_srand($_SESSION['seed']);
$str_long1 = "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";

$str_show = 'faANNqh47O';

for ($value = 0; $value < strlen($str_show); $value++) {
    echo strpos($str_long1, substr($str_show, $value, 1)) . ' ' . strpos($str_long1, substr($str_show, $value, 1)) . ' 0 61  ';
}
```

用[php\_mt\_seed](https://www.openwall.com/php_mt_seed/)爆破

写个脚本代入就出了

```
<?php
mt_srand(50560444);

$str_long1 = "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
$str='';
$len1=20;
for ( $i = 0; $i < $len1; $i++ ){
    $str.=substr($str_long1, mt_rand(0, strlen($str_long1) - 1), 1);
}
echo $str;

?>
```

这题比较坑的是PHP版本必须在7.1以上，我拿着5.6去弄，就踩坑了，贼恶心，不够细心。


---

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