diff --git a/pom.xml b/pom.xml
index 113730e..d67970d 100644
--- a/pom.xml
+++ b/pom.xml
@@ -62,28 +62,28 @@
       <dependency>
         <groupId>junit</groupId>
         <artifactId>junit</artifactId>
-        <version>4.13</version>
+        <version>4.13.1</version>
         <scope>test</scope>
       </dependency>
 
       <dependency>
         <groupId>org.powermock</groupId>
         <artifactId>powermock-module-junit4</artifactId>
-        <version>${powermock.version}</version>
+        <version>2.0.7</version>
         <scope>test</scope>
       </dependency>
 
       <dependency>
         <groupId>org.powermock</groupId>
         <artifactId>powermock-api-mockito2</artifactId>
-        <version>${powermock.version}</version>
+        <version>2.0.7</version>
         <scope>test</scope>
       </dependency>
 
       <dependency>
         <groupId>org.assertj</groupId>
         <artifactId>assertj-core</artifactId>
-        <version>3.15.0</version>
+        <version>3.18.1</version>
         <scope>test</scope>
       </dependency>
     </dependencies>