diff --git a/core/build.gradle b/core/build.gradle
index 4c494ee..46c6d37 100644
--- a/core/build.gradle
+++ b/core/build.gradle
@@ -13,7 +13,7 @@ compileJava {
 dependencies {
     api fileTree(dir: 'libs', include: ['*.jar'])
 
-    api 'com.google.guava:guava:20.0' //TODO ToStringHelper update for updating to ?
+    api 'com.google.guava:guava:23.0' //TODO ToStringHelper update for updating to ?
     api 'com.google.code.findbugs:jsr305:3.0.2'
     api 'com.madgag.spongycastle:core:1.58.0.0'
     api 'com.lambdaworks:scrypt:1.4.0'