diff --git a/samples/sample-spring-boot-echo-kotlin/build.gradle.kts b/samples/sample-spring-boot-echo-kotlin/build.gradle.kts
index a16bdf460..459d77ba0 100644
--- a/samples/sample-spring-boot-echo-kotlin/build.gradle.kts
+++ b/samples/sample-spring-boot-echo-kotlin/build.gradle.kts
@@ -17,8 +17,8 @@
 plugins {
     id("sdk.java-library")
     id("sdk.spring-boot")
-    kotlin("jvm") version "1.9.20"
-    kotlin("plugin.spring") version "1.9.20"
+    kotlin("jvm") version "1.9.21"
+    kotlin("plugin.spring") version "1.9.21"
 }
 
 dependencies {