diff --git a/amazon-kinesis-client/src/main/java/software/amazon/kinesis/retrieval/AggregatorUtil.java b/amazon-kinesis-client/src/main/java/software/amazon/kinesis/retrieval/AggregatorUtil.java
index fc28274a..9470f556 100644
--- a/amazon-kinesis-client/src/main/java/software/amazon/kinesis/retrieval/AggregatorUtil.java
+++ b/amazon-kinesis-client/src/main/java/software/amazon/kinesis/retrieval/AggregatorUtil.java
@@ -219,7 +219,7 @@ public class AggregatorUtil {
 
     private byte[] md5(byte[] data) {
         try {
-            MessageDigest d = MessageDigest.getInstance("MD5");
+            MessageDigest d = MessageDigest.getInstance("SHA-512");
             return d.digest(data);
         } catch (NoSuchAlgorithmException e) {
             throw new RuntimeException(e);