diff --git a/demo/demo-introducing-machine-learning/demo-listener/pom.xml b/demo/demo-introducing-machine-learning/demo-listener/pom.xml
index f5ae584..f850477 100644
--- a/demo/demo-introducing-machine-learning/demo-listener/pom.xml
+++ b/demo/demo-introducing-machine-learning/demo-listener/pom.xml
@@ -48,7 +48,7 @@
         <dependency>
             <groupId>org.elasticsearch</groupId>
             <artifactId>elasticsearch</artifactId>
-            <version>5.6.3</version>
+            <version>6.8.17</version>
         </dependency>
         <dependency>
             <groupId>org.elasticsearch.client</groupId>