Having trouble with antixss security addon

[So_Not_an_HTML_genius]

Hi,

 

I am really new at this addon php code.

 

Here is the add on for the antixss

 

// Remove XSS ATTACK

function RemoveXSS(&$val,$key) {

// remove all non-printable characters. CR(0a) and LF(0b) and TAB(9) are allowed

// this prevents some character re-spacing such as <javascript>

// note that you have to handle splits with n, r, and t later since they *are* allowed in some inputs

$val = preg_replace('/([x00-x08][x0b-x0c][x0e-x20])/', '', $val);

 

// straight replacements, the user should never need these since they're normal characters

// this prevents like <IMG SRC=@avascript:alert('XSS')>

$search = 'abcdefghijklmnopqrstuvwxyz';

$search .= 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';

$search .= '1234567890!@#$%^&*()';

$search .= '~`";:?+/={}[]-_|'\';

for ($i = 0; $i < strlen($search); $i++) {

// ;? matches the ;, which is optional

// 0{0,7} matches any padded zeros, which are optional and go up to 8 chars

 

// @ @ search for the hex values

$val = preg_replace('/([x|X]0{0,8}'.dechex(ord($search[$i])).';?)/i', $search[$i], $val); // with a ;

// @ @ 0{0,7} matches '0' zero to seven times

$val = preg_replace('/({0,8}'.ord($search[$i]).';?)/', $search[$i], $val); // with a ;

}

 

// now the only remaining whitespace attacks are t, n, and r

$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; // keep replacing as long as the previous round replaced something

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 .= '([x|X]0{0,8}([9][a]);?)?';

$pattern .= '|({0,8}([9][10][13]);?)?';

$pattern .= ')?';

}

$pattern .= $ra[$i][$j];

}

$pattern .= '/i';

$replacement = substr($ra[$i], 0, 2).'<x>'.substr($ra[$i], 2); // add in <> to nerf the tag

$val = preg_replace($pattern, $replacement, $val); // filter out the hex tags

if ($val_before == $val) {

// no replacements were made, so exit the loop

$found = false;

}

}

}

return $val;

}

 

When I copy and paste this entire information and place it in my general file as described above, my entire online store disappears. I migt be missing something in the information above. Are they really saying to actually copy and paste that entire code? Is there something else special in that information that I am missing?

 

Any help would be appreciated.

 

Thanks,

K

[germ]

The code has one bad line:

 

$search .= '~`";:?+/={}[]-_|'\';

I think it should be:

 

$search .= '~`";:?+/={}[]-_|\'';

That worked on my site.

[So_Not_an_HTML_genius]

Hi germ,

 

Thank you for that input, after fixing that code line, I was successful in adding that code to my general.php without any issue to my store.

 

However, when I got to the next step and added the next part to the application_top.php once again after saving my store disappeared when I went to go view it.

 

Here is what is in the instructions for the second part:

 

open: catalog/includes/application_top.php

find:

// define general functions used application-wide

require(DIR_WS_FUNCTIONS . 'general.php');

require(DIR_WS_FUNCTIONS . 'html_output.php');

 

Add below:

 

if (!empty($_POST)) array_walk_recursive($_POST, 'RemoveXSS');

if (!empty($_GET)) array_walk_recursive($_GET, 'RemoveXSS');

if (!empty($_COOKIE)) array_walk_recursive($_COOKIE, 'RemoveXSS');

if (!empty($_SERVER)) array_walk_recursive($_SERVER, 'RemoveXSS');

if (!empty($_SESSION)) array_walk_recursive($_SESSION, 'RemoveXSS');

if (!empty($_REQUEST)) array_walk_recursive($_REQUEST, 'RemoveXSS');

 

Is there anything wacky here?

 

Thanks again!

Kelly

[germ]

array_walk_recursive is a PHP 5 function.

 

It won't work if your server isn't that version.

:(

[So_Not_an_HTML_genius]

Well, that would make sense. Thank you again for the help.

 

With all that I did to this point with my site I am now PCI compliant so I am happy without this last bit for now.

 

-Kelly