    public function hasTag ($tag, array $oldTags=null, $refresh=false) {
        $oldTags = $oldTags === null ? $this->getTags ($refresh) : $oldTags;
        return in_array (strtolower (Tags::normalizeTag ($tag)), array_map (function ($tag) {
            return strtolower ($tag); 
        }, $oldTags));
    }
The software 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.