diff --git a/build.gradle b/build.gradle
index 21a25440..9f9ad2ad 100644
--- a/build.gradle
+++ b/build.gradle
@@ -134,7 +134,7 @@ dependencies {
     implementation "com.auth0:java-jwt:4.4.0"
     implementation "net.jodah:failsafe:2.4.4"
 
-    testImplementation "org.bouncycastle:bcprov-jdk15on:1.70"
+    testImplementation "org.bouncycastle:bcprov-jdk18on:1.78"
     testImplementation "org.mockito:mockito-core:4.8.1"
     testImplementation "com.squareup.okhttp3:mockwebserver:${okhttpVersion}"
     testImplementation "org.hamcrest:hamcrest:${hamcrestVersion}"