diff --git a/build.gradle b/build.gradle
index 17947e8f188497cd9c0a458ce23675709f9ac640..4980dde9598b95794ca285b052af0b3b3df0c017 100644
--- a/build.gradle
+++ b/build.gradle
@@ -49,7 +49,7 @@ project(":de.bmotionstudio.gef.editor") {
 	}
 
 	dependencies {
-		implementation group: "com.thoughtworks.xstream", name: "xstream", version: "1.4.19"
+		implementation group: "com.thoughtworks.xstream", name: "xstream", version: "1.4.20"
 		// Current versions of XStream depend on MXParser, but not any specific version of it.
 		// To avoid the version number changing unexpectedly and breaking the MANIFEST.MF classpath entries,
 		// hardcode a specific MXParser version here.
diff --git a/de.bmotionstudio.gef.editor/.classpath b/de.bmotionstudio.gef.editor/.classpath
index bb3c0f50653da482432818df3f15bb10c8fc9760..b1726716b11c97724f9c7436f66766692a39c40f 100644
--- a/de.bmotionstudio.gef.editor/.classpath
+++ b/de.bmotionstudio.gef.editor/.classpath
@@ -9,5 +9,5 @@
 	<classpathentry kind="output" path="bin"/>
 	<classpathentry exported="true" kind="lib" path="lib/dependencies/mxparser-1.2.2.jar"/>
 	<classpathentry exported="true" kind="lib" path="lib/dependencies/xmlpull-1.1.3.1.jar"/>
-	<classpathentry exported="true" kind="lib" path="lib/dependencies/xstream-1.4.19.jar"/>
+	<classpathentry exported="true" kind="lib" path="lib/dependencies/xstream-1.4.20.jar"/>
 </classpath>
diff --git a/de.bmotionstudio.gef.editor/META-INF/MANIFEST.MF b/de.bmotionstudio.gef.editor/META-INF/MANIFEST.MF
index 2a744d8b2f9575a8a11aa935ee07e42ab23886a8..34f3a964dc762c3186f8fd723373f127cfdd512f 100644
--- a/de.bmotionstudio.gef.editor/META-INF/MANIFEST.MF
+++ b/de.bmotionstudio.gef.editor/META-INF/MANIFEST.MF
@@ -151,7 +151,7 @@ Export-Package: de.bmotionstudio.gef.editor;
 Bundle-ClassPath: .,
  lib/dependencies/mxparser-1.2.2.jar,
  lib/dependencies/xmlpull-1.1.3.1.jar,
- lib/dependencies/xstream-1.4.19.jar,
+ lib/dependencies/xstream-1.4.20.jar,
  lib/ext/groovy-2.0.5.jar,
  lib/ext/asm-4.0.jar,
  lib/ext/antlr-2.7.7.jar