diff --git a/src/main/java/sirius/kernel/xml/XMLGenerator.java b/src/main/java/sirius/kernel/xml/XMLGenerator.java
index dcb80198..600b609f 100644
--- a/src/main/java/sirius/kernel/xml/XMLGenerator.java
+++ b/src/main/java/sirius/kernel/xml/XMLGenerator.java
@@ -16,6 +16,7 @@
 
 import javax.annotation.Nullable;
 import javax.annotation.ParametersAreNonnullByDefault;
+import javax.xml.XMLConstants;
 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;
 import javax.xml.parsers.ParserConfigurationException;
@@ -146,6 +147,7 @@ public static Document createDocument(@Nullable String namespaceURI,
                                           String qualifiedName,
                                           @Nullable DocumentType docType) throws ParserConfigurationException {
         DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
+        factory.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, true);
         DocumentBuilder builder = factory.newDocumentBuilder();
         DOMImplementation impl = builder.getDOMImplementation();
         return impl.createDocument(namespaceURI, qualifiedName, docType);
diff --git a/src/main/java/sirius/kernel/xml/XMLReader.java b/src/main/java/sirius/kernel/xml/XMLReader.java
index 46259bc7..a52e7cd4 100644
--- a/src/main/java/sirius/kernel/xml/XMLReader.java
+++ b/src/main/java/sirius/kernel/xml/XMLReader.java
@@ -17,6 +17,7 @@
 import sirius.kernel.commons.Strings;
 import sirius.kernel.health.Exceptions;
 
+import javax.xml.XMLConstants;
 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;
 import javax.xml.parsers.ParserConfigurationException;
@@ -63,7 +64,9 @@ public class XMLReader extends DefaultHandler {
      */
     public XMLReader() {
         try {
-            documentBuilder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
+            DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
+            documentBuilderFactory.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, true);
+            documentBuilder = documentBuilderFactory.newDocumentBuilder();
             taskContext = TaskContext.get();
         } catch (ParserConfigurationException exception) {
             throw Exceptions.handle(exception);
@@ -178,6 +181,7 @@ static class UserInterruptException extends RuntimeException {
     public void parse(InputStream stream, Function<String, InputStream> resourceLocator) throws IOException {
         try (stream) {
             SAXParserFactory factory = SAXParserFactory.newInstance();
+            factory.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, true);
             SAXParser saxParser = factory.newSAXParser();
             org.xml.sax.XMLReader reader = saxParser.getXMLReader();
             reader.setEntityResolver(new EntityResolver() {
diff --git a/src/main/java/sirius/kernel/xml/XMLStructuredInput.java b/src/main/java/sirius/kernel/xml/XMLStructuredInput.java
index 5e93e8aa..dda55017 100644
--- a/src/main/java/sirius/kernel/xml/XMLStructuredInput.java
+++ b/src/main/java/sirius/kernel/xml/XMLStructuredInput.java
@@ -14,6 +14,7 @@
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
+import javax.xml.XMLConstants;
 import javax.xml.namespace.NamespaceContext;
 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;
@@ -38,6 +39,7 @@ public class XMLStructuredInput implements StructuredInput {
     public XMLStructuredInput(InputStream inputStream, @Nullable NamespaceContext namespaceContext) throws IOException {
         try {
             DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
+            factory.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, true);
             if (namespaceContext != null) {
                 factory.setNamespaceAware(true);
             }