JSIEVE-111 Upgrade Guava 18.0 -> 25.1-jre
diff --git a/pom.xml b/pom.xml
index 256b4af..0aa8147 100644
--- a/pom.xml
+++ b/pom.xml
@@ -84,7 +84,7 @@
         <commons-io.version>2.1</commons-io.version>
         <mockito-core.version>3.0.0</mockito-core.version>
         <assertj.version>1.7.1</assertj.version>
-        <guava.version>18.0</guava.version>
+        <guava.version>25.1-jre</guava.version>
         <mime4j.version>0.8.3</mime4j.version>
     </properties>