Language: Java
Label: vulnerable
CWE: CWE-611 \u2014 Improper Restriction of XML External Entity Reference
The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output.

Code:
	public static String xmlToString(Document model) {
		StringWriter s = new StringWriter();
		DOMSource domSource = new DOMSource(model);
		StreamResult streamResult = new StreamResult(s);
		TransformerFactory tf = TransformerFactory.newInstance();
		Transformer serializer;
		try {
			serializer = tf.newTransformer();
			serializer.setOutputProperty(OutputKeys.INDENT, "yes");
			serializer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "1");
			serializer.transform(domSource, streamResult);
		} catch (Exception e) {
			e.printStackTrace(new PrintWriter(s));
		}
		return s.toString();
	}