Html Tags filter

aracnet · New Member Joined: Oct 31, 2004 Posts: 3

Once madman offered me the following script if you do not have magic quotes in mainfile.php.

I wanted to expand it for filtering scripts and tags. by renaming them like below . It does not work it doenst change the strings which has "script" in it. Where is the error?

Code:

reset($_REQUEST);
foreach ($_REQUEST as $seckey => $secvalue)
{
$secvalue = strtolower($secvalue);
if (get_magic_quotes_gpc()) $secvalue = stripslashes($secvalue);
$secvalue = str_replace('\\', '&'.'#92;', $secvalue);
$secvalue = str_replace('\'', '&'.'#39;', $secvalue);
$secvalue = str_replace('"', '&'.'quot;', $secvalue);
$secvalue = str_replace("\x00", '', $secvalue);
$secvalue = str_replace('script', 'scprt', $secvalue);
$secvalue = str_replace('style', 'styyle', $secvalue);

if (isset($_GET[$seckey])) $_GET[$seckey] = $secvalue;
if (isset($_POST[$seckey])) $_POST[$seckey] = $secvalue;
if (isset($_COOKIE[$seckey])) $_COOKIE[$seckey] = $secvalue;
if (isset($HTTP_GET_VARS[$seckey])) $HTTP_GET_VARS[$seckey] = $secvalue;
if (isset($HTTP_POST_VARS[$seckey])) $HTTP_POST_VARS[$seckey] = $secvalue;
if (isset($HTTP_COOKIE_VARS[$seckey])) $HTTP_COOKIE_VARS[$seckey] = $secvalue;
}

Also i am wondering how forum module in nuke can allow scripts inside [ code ] tag. Although there is a filter for scripots in mainfile.php as :

Code:

foreach ($_GET as $sec_key => $secvalue) {
if ((eregi("<[^>]*script*\"?[^>]*>", $secvalue)) ||
(eregi("<[^>]*object*\"?[^>]*>", $secvalue)) ||
(eregi("<[^>]*iframe*\"?[^>]*>", $secvalue)) ||
(eregi("<[^>]*applet*\"?[^>]*>", $secvalue)) ||
(eregi("<[^>]*meta*\"?[^>]*>", $secvalue)) ||
(eregi("<[^>]*style*\"?[^>]*>", $secvalue)) ||
(eregi("<[^>]*form*\"?[^>]*>", $secvalue)) ||
(eregi("<[^>]*img*\"?[^>]*>", $secvalue)) ||
(eregi("<[^>]*onmouseover*\"?[^>]*>", $secvalue)) ||
(eregi("$[^>]*\"?[^)]*$", $secvalue)) ||
(eregi("\"", $secvalue)) ||
(eregi("forum_admin", $sec_key)) ||
(eregi("inside_mod", $sec_key))) {
die ("<center><img src=images/logo.gif> The html tags you attempted to use are not allowed [ <a href=\"javascript:history.go(-1)\">Go Back</a> ]");
}
}

foreach ($_POST as $secvalue) {
if ((eregi("<[^>]*onmouseover*\"?[^>]*>", $secvalue)) || (eregi("<[^>]*script*\"?[^>]*>", $secvalue)) || (eregi("<[^>]*style*\"?[^>]*>", $secvalue))) {
die ("<center><img src=images/logo.gif> The html tags you attempted to use are not allowed [ <a href=\"javascript:history.go(-1)\">Go Back</a> ]");
}
}

I just want to make it same as in my other modules.[/quote]

Raven · Posted: Fri Apr 08, 2005 10:53 pm

Just a guess, but I see a possible typo

Code:

$secvalue = str_replace('script', 'scprt', $secvalue);

Did you mean scrpt instead of scprt?

aracnet · New Member Joined: Oct 31, 2004 Posts: 3

All i wanted to do is fillter all types of Requests in nuke(cookie,post or get).
For example is someone sends a string which includes "script" then i wanted to turn it with "scrpt" word.

Or at least i wanted to use [co de] funtion that is used as in forums module. Because if someone posts a string that includes "script" to my module it is automatically blocked by default nuke filter . Instead of it want to change string or hight as in forums .
I do not want to totally remove filter becasue as i know there are many modules and exploits still exits in nuke.