diff --git a/plugins/json/src/main/java/org/apache/struts2/json/JSONWriter.java b/plugins/json/src/main/java/org/apache/struts2/json/JSONWriter.java
index 20f815c71..0e10ccf85 100644
--- a/plugins/json/src/main/java/org/apache/struts2/json/JSONWriter.java
+++ b/plugins/json/src/main/java/org/apache/struts2/json/JSONWriter.java
@@ -20,6 +20,7 @@
  */
 package org.apache.struts2.json;
 
+import com.opensymphony.xwork2.util.ProxyUtil;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.apache.struts2.json.annotations.JSON;
@@ -210,7 +211,7 @@ public class JSONWriter {
         BeanInfo info;
 
         try {
-            Class clazz = object.getClass();
+            Class clazz = ProxyUtil.ultimateTargetClass(object);
 
             info = ((object == this.root) && this.ignoreHierarchy)
                     ? getBeanInfoIgnoreHierarchy(clazz)