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:
    public function serialize()
    {
        $this->getDefinition('HTML');
        $this->getDefinition('CSS');
        $this->getDefinition('URI');
        return serialize($this);
    }