dede 修补XSS跨站脚本攻击

XSS又叫CSS (Cross Site Script) ，跨站脚本攻击。它指的是恶意攻击者往Web页面里插入恶意html代码，当用户浏览该页之时，嵌入其中Web里面的html代码会被执行，从而达到恶意 攻击用户的特殊目的。XSS属于被动式的攻击，因为其被动且不好利用，所以许多人常忽略其危害性。而本文主要讲的是利用XSS得到目标服务器的 shell。技术虽然是老技术，但是其思路希望对大家有帮助。

首先打开文件:/include/common.func.php
在文件中加入函数

function RemoveXSS($val) {
 $val = preg_replace('/([\x00-\x08,\x0b-\x0c,\x0e-\x19])/', '', $val);

 $search = 'abcdefghijklmnopqrstuvwxyz';
 $search .= 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
 $search .= '1234567890!@#$%^&*()';
 $search .= '~`";:?+/={}[]-_|\'\\';
 for ($i = 0; $i < strlen($search); $i++) {
 $val = preg_replace('/(&#[xX]0{0,8}'.dechex(ord($search[$i])).';?)/i', $search[$i], $val);
 $val = preg_replace('/(&#0{0,8}'.ord($search[$i]).';?)/', $search[$i], $val);
 }

 $ra1 = array('javascript', 'vbscript', 'expression', 'applet', 'meta', 'xml', 'blink', 'link', 'style', 'script', 'embed', 'object', 'iframe', 'frame', 'frameset', 'ilayer', 'layer', 'bgsound', 'title', 'base');
 $ra2 = array('onabort', 'onactivate', 'onafterprint', 'onafterupdate', 'onbeforeactivate', 'onbeforecopy', 'onbeforecut', 'onbeforedeactivate', 'onbeforeeditfocus', 'onbeforepaste', 'onbeforeprint', 'onbeforeunload', 'onbeforeupdate', 'onblur', 'onbounce', 'oncellchange', 'onchange', 'onclick', 'oncontextmenu', 'oncontrolselect', 'oncopy', 'oncut', 'ondataavailable', 'ondatasetchanged', 'ondatasetcomplete', 'ondblclick', 'ondeactivate', 'ondrag', 'ondragend', 'ondragenter', 'ondragleave', 'ondragover', 'ondragstart', 'ondrop', 'onerror', 'onerrorupdate', 'onfilterchange', 'onfinish', 'onfocus', 'onfocusin', 'onfocusout', 'onhelp', 'onkeydown', 'onkeypress', 'onkeyup', 'onlayoutcomplete', 'onload', 'onlosecapture', 'onmousedown', 'onmouseenter', 'onmouseleave', 'onmousemove', 'onmouseout', 'onmouseover', 'onmouseup', 'onmousewheel', 'onmove', 'onmoveend', 'onmovestart', 'onpaste', 'onpropertychange', 'onreadystatechange', 'onreset', 'onresize', 'onresizeend', 'onresizestart', 'onrowenter', 'onrowexit', 'onrowsdelete', 'onrowsinserted', 'onscroll', 'onselect', 'onselectionchange', 'onselectstart', 'onstart', 'onstop', 'onsubmit', 'onunload');
 $ra = array_merge($ra1, $ra2);

 $found = true;
 while ($found == true) {
 $val_before = $val;
 for ($i = 0; $i < sizeof($ra); $i++) {
 $pattern = '/';
 for ($j = 0; $j < strlen($ra[$i]); $j++) {
 if ($j > 0) {
 $pattern .= '(';
 $pattern .= '(&#[xX]0{0,8}([9ab]);)';
 $pattern .= '|';
 $pattern .= '|(&#0{0,8}([9|10|13]);)';
 $pattern .= ')*';
 }
 $pattern .= $ra[$i][$j];
 }
 $pattern .= '/i';
 $replacement = substr($ra[$i], 0, 2).'<x>'.substr($ra[$i], 2);
 $val = preg_replace($pattern, $replacement, $val);
 if ($val_before == $val) {
 $found = false;
 }
 }
 }
 return $val;
}

1. <p>
2.         搜索 <strong class="fc_03c">{dede:global name='keyword'/}</strong> 的结果
3.     </p>

修改为:

1. <p>
2.      搜索 <strong class="fc_03c">{dede:global name='keyword' function='RemoveXSS(@me)'/}</strong> 的结果
3.  </p>