diff --git a/showcase/gapic-showcase/pom.xml b/showcase/gapic-showcase/pom.xml
index 331146b5d8..7398de2839 100644
--- a/showcase/gapic-showcase/pom.xml
+++ b/showcase/gapic-showcase/pom.xml
@@ -244,7 +244,7 @@
         <dependency>
           <groupId>ch.qos.logback</groupId>
           <artifactId>logback-core</artifactId>
-          <version>1.5.16</version>
+          <version>1.3.15</version>
           <scope>test</scope>
         </dependency>
       </dependencies>
@@ -288,7 +288,7 @@
         <dependency>
           <groupId>ch.qos.logback</groupId>
           <artifactId>logback-core</artifactId>
-          <version>1.2.13</version>
+          <version>1.3.15</version>
           <scope>test</scope>
         </dependency>
       </dependencies>
@@ -333,7 +333,7 @@
         <dependency>
           <groupId>ch.qos.logback</groupId>
           <artifactId>logback-core</artifactId>
-          <version>1.2.13</version>
+          <version>1.3.15</version>
           <scope>test</scope>
         </dependency>
       </dependencies>