diff --git a/build.gradle b/build.gradle
index d64df02..bd39c2d 100644
--- a/build.gradle
+++ b/build.gradle
@@ -2,7 +2,7 @@
 
 buildscript {
     ext.jetty_version = '9.2.30.v20200428'
-    ext.kotlin_version = '1.6.10'
+    ext.kotlin_version = '1.6.21'
 
     repositories {
         google()