diff --git a/WebGoat/webgoat-lessons/pom.xml b/WebGoat/webgoat-lessons/pom.xml
index 1d97b01..9e7bc08 100644
--- a/WebGoat/webgoat-lessons/pom.xml
+++ b/WebGoat/webgoat-lessons/pom.xml
@@ -86,7 +86,7 @@
         <dependency>
             <groupId>com.thoughtworks.xstream</groupId>
             <artifactId>xstream</artifactId>
-            <version>1.4.7</version>
+            <version>1.4.18</version>
         </dependency>
     </dependencies>
     <dependencyManagement>
diff --git a/WebGoat/webgoat-lessons/vulnerable-components/pom.xml b/WebGoat/webgoat-lessons/vulnerable-components/pom.xml
index cb0623e..e77b13a 100644
--- a/WebGoat/webgoat-lessons/vulnerable-components/pom.xml
+++ b/WebGoat/webgoat-lessons/vulnerable-components/pom.xml
@@ -12,7 +12,7 @@
         <dependency>
             <groupId>com.thoughtworks.xstream</groupId>
             <artifactId>xstream</artifactId>
-            <version>1.4.7</version>
+            <version>1.4.18</version>
         </dependency>
         <dependency>
             <groupId>cglib</groupId>