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 transform($attr, $config, $context)
    {
        if (!isset($attr[$this->attr])) {
            return $attr;
        }

        $width = $this->confiscateAttr($attr, $this->attr);
        // some validation could happen here

        if (!isset($this->css[$this->attr])) {
            return $attr;
        }

        $style = '';
        foreach ($this->css[$this->attr] as $suffix) {
            $property = "margin-$suffix";
            $style .= "$property:{$width}px;";
        }
        $this->prependCSS($attr, $style);
        return $attr;
    }