CVE-2026-6857

@@ -19,17 +19,28 @@
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
+import java.io.ObjectInputFilter;
 import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
 
 import org.apache.camel.support.DefaultExchangeHolder;
 import org.apache.camel.util.ClassLoadingAwareObjectInputStream;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * Utilities for {@link DefaultExchangeHolder} and the Infinispan Protostream marshaller.
  */
 final class DefaultExchangeHolderUtils {
 
+    /**
+     * Default deserialization filter that restricts which classes can be deserialized. Allows standard Java types and
+     * Apache Camel types. Can be overridden via the JVM system property {@code jdk.serialFilter}.
+     */
+    static final String DEFAULT_DESERIALIZATION_FILTER = "java.**;javax.**;org.apache.camel.**;!*";
+
+    private static final Logger LOG = LoggerFactory.getLogger(DefaultExchangeHolderUtils.class);
+
     private DefaultExchangeHolderUtils() {
         // Utility class
     }
@@ -46,6 +57,14 @@ static byte[] serialize(DefaultExchangeHolder holder) {
     static DefaultExchangeHolder deserialize(byte[] bytes) {
         try (ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
              ObjectInputStream ois = new ClassLoadingAwareObjectInputStream(bais)) {
+            ObjectInputFilter jvmFilter = ObjectInputFilter.Config.getSerialFilter();
+            if (jvmFilter != null) {
+                ois.setObjectInputFilter(jvmFilter);
+            } else {
+                LOG.debug("No JVM-wide deserialization filter set, applying default Camel filter: {}",
+                        DEFAULT_DESERIALIZATION_FILTER);
+                ois.setObjectInputFilter(ObjectInputFilter.Config.createFilter(DEFAULT_DESERIALIZATION_FILTER));
+            }
             return (DefaultExchangeHolder) ois.readObject();
         } catch (IOException | ClassNotFoundException e) {
             throw new RuntimeException(e);

@@ -0,0 +1,37 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.example.external;
+
+import java.io.Serializable;
+
+/**
+ * Serializable type living outside the {@code java.**}, {@code javax.**} and {@code org.apache.camel.**} packages, used
+ * to verify that the default deserialization allowlist rejects unknown classes.
+ */
+public final class NotAllowedSerializable implements Serializable {
+    private static final long serialVersionUID = 1L;
+
+    private final String value;
+
+    public NotAllowedSerializable(String value) {
+        this.value = value;
+    }
+
+    public String getValue() {
+        return value;
+    }
+}

@@ -0,0 +1,63 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.camel.component.infinispan.remote.protostream;
+
+import java.io.ByteArrayOutputStream;
+import java.io.ObjectOutputStream;
+
+import com.example.external.NotAllowedSerializable;
+import org.apache.camel.impl.DefaultCamelContext;
+import org.apache.camel.support.DefaultExchange;
+import org.apache.camel.support.DefaultExchangeHolder;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+public class DefaultExchangeHolderUtilsTest {
+
+    @Test
+    public void testDeserializeAcceptsDefaultExchangeHolder() {
+        DefaultCamelContext context = new DefaultCamelContext();
+        DefaultExchange exchange = new DefaultExchange(context);
+        exchange.getIn().setBody("hello");
+
+        DefaultExchangeHolder holder = DefaultExchangeHolder.marshal(exchange, true);
+        byte[] bytes = DefaultExchangeHolderUtils.serialize(holder);
+
+        DefaultExchangeHolder roundTripped = DefaultExchangeHolderUtils.deserialize(bytes);
+        assertNotNull(roundTripped);
+
+        DefaultExchange restored = new DefaultExchange(context);
+        DefaultExchangeHolder.unmarshal(restored, roundTripped);
+        assertEquals("hello", restored.getIn().getBody());
+    }
+
+    @Test
+    public void testDeserializeRejectsUnlistedType() throws Exception {
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        try (ObjectOutputStream oos = new ObjectOutputStream(baos)) {
+            oos.writeObject(new NotAllowedSerializable("blocked"));
+        }
+
+        RuntimeException thrown = assertThrows(RuntimeException.class,
+                () -> DefaultExchangeHolderUtils.deserialize(baos.toByteArray()));
+        Throwable cause = thrown.getCause();
+        assertNotNull(cause);
+    }
+}