From 345a8534ff39cc9550cbacabe2b3fffe20293508 Mon Sep 17 00:00:00 2001 From: Thomas Lenz Date: Thu, 22 Jun 2017 14:26:15 +0200 Subject: implement a workaround to fix XXE and SSRF problems in an old XMLStreamParser implementation of a third party library --- .../java/at/gv/egiz/slbinding/SLUnmarshaller.java | 70 +++++++++++++++++++--- 1 file changed, 63 insertions(+), 7 deletions(-) (limited to 'utils/src/main/java/at/gv') diff --git a/utils/src/main/java/at/gv/egiz/slbinding/SLUnmarshaller.java b/utils/src/main/java/at/gv/egiz/slbinding/SLUnmarshaller.java index de1b2ddf..2d1808c8 100644 --- a/utils/src/main/java/at/gv/egiz/slbinding/SLUnmarshaller.java +++ b/utils/src/main/java/at/gv/egiz/slbinding/SLUnmarshaller.java @@ -25,7 +25,10 @@ package at.gv.egiz.slbinding; +import java.io.ByteArrayInputStream; import java.io.IOException; +import java.io.InputStreamReader; +import java.io.Reader; import java.net.URL; import java.util.Arrays; import java.util.Collection; @@ -38,6 +41,8 @@ import javax.xml.bind.JAXBException; import javax.xml.bind.UnmarshalException; import javax.xml.bind.Unmarshaller; import javax.xml.bind.ValidationEvent; +import javax.xml.parsers.DocumentBuilderFactory; +import javax.xml.parsers.ParserConfigurationException; import javax.xml.stream.XMLEventReader; import javax.xml.stream.XMLInputFactory; import javax.xml.stream.XMLStreamException; @@ -46,6 +51,7 @@ import javax.xml.transform.stream.StreamSource; import javax.xml.validation.Schema; import javax.xml.validation.SchemaFactory; +import org.apache.commons.io.IOUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.xml.sax.SAXException; @@ -237,17 +243,67 @@ public class SLUnmarshaller { public Object unmarshal(StreamSource source) throws XMLStreamException, JAXBException { ReportingValidationEventHandler validationEventHandler = new ReportingValidationEventHandler(); -// System.setProperty("javax.xml.stream.XMLInputFactory", "com.sun.xml.stream.ZephyrParserFactory"); -// System.setProperty("com.sun.xml.stream.ZephyrParserFactory", "com.sun.xml.stream.ZephyrParserFactory"); -// XMLInputFactory inputFactory = XMLInputFactory.newInstance("com.sun.xml.stream.ZephyrParserFactory", null); - + Reader inputReader = source.getReader(); + + if (inputReader instanceof InputStreamReader) { + DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); + + try { + dbf.setFeature("http://xml.org/sax/features/external-general-entities", false); + dbf.setFeature("http://xml.org/sax/features/external-parameter-entities", false); + dbf.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true); + dbf.setFeature("http://apache.org/xml/features/nonvalidating/load-external-dtd", false); + + } catch (ParserConfigurationException e) { + log.error("Can NOT set Xerces parser security features. -> XML parsing is possible insecure!!!! ", e); + + } + + try { + //create copy of input stream + InputStreamReader isReader = (InputStreamReader) inputReader; + String encoding = isReader.getEncoding(); + byte[] backup = IOUtils.toByteArray(isReader, encoding); + + //validate input stream + dbf.newDocumentBuilder().parse(new ByteArrayInputStream(backup)); + + //create new inputStreamReader for reak processing + inputReader = new InputStreamReader(new ByteArrayInputStream(backup), encoding); + + + } catch (SAXException e) { + log.error("XML data validation FAILED with msg: " + e.getMessage(), e); + throw new XMLStreamException("XML data validation FAILED with msg: " + e.getMessage(), e); + + + } catch (ParserConfigurationException e) { + log.error("XML data validation FAILED with msg: " + e.getMessage(), e); + throw new XMLStreamException("XML data validation FAILED with msg: " + e.getMessage(), e); + + } catch (IOException e) { + log.error("XML data validation FAILED with msg: " + e.getMessage(), e); + throw new XMLStreamException("XML data validation FAILED with msg: " + e.getMessage(), e); + + } + + } else { + log.error("!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!"); + log.error("Reader is not of type InputStreamReader -> can not make a copy of the InputStream --> extended XML validation is not possible!!! "); + log.error("!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!"); + + } + + //parse XML with original functionality XMLInputFactory inputFactory = XMLInputFactory.newInstance(); //disallow DTD and external entities inputFactory.setProperty(XMLInputFactory.SUPPORT_DTD, false); inputFactory.setProperty("javax.xml.stream.isSupportingExternalEntities", false); - XMLEventReader eventReader = inputFactory.createXMLEventReader(source.getReader()); + + + XMLEventReader eventReader = inputFactory.createXMLEventReader(inputReader); RedirectEventFilter redirectEventFilter = new RedirectEventFilter(); XMLEventReader filteredReader = inputFactory.createFilteredReader(eventReader, redirectEventFilter); @@ -255,8 +311,8 @@ public Object unmarshal(StreamSource source) throws XMLStreamException, JAXBExce unmarshaller.setEventHandler(validationEventHandler); unmarshaller.setListener(new RedirectUnmarshallerListener(redirectEventFilter)); - unmarshaller.setSchema(slSchema); - + unmarshaller.setSchema(slSchema); + Object object; try { log.trace("Before unmarshal()."); -- cgit v1.2.3