diff --git a/pom.xml b/pom.xml
index 86c6a91..936a4f7 100644
--- a/pom.xml
+++ b/pom.xml
@@ -118,7 +118,7 @@
       <dependency>
         <groupId>ch.qos.logback</groupId>
         <artifactId>logback-classic</artifactId>
-        <version>1.5.20</version>
+        <version>1.5.21</version>
       </dependency>
       <dependency>
         <groupId>commons-codec</groupId>