Language: PHP
Label: safe
CWE: CWE-79 \u2014 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

Code:
function HTMLPurifier($html, $config = null)
{
    static $purifier = false;
    if (!$purifier) {
        $purifier = new HTMLPurifier();
    }
    return $purifier->purify($html, $config);
}