diff --git a/dependency-check-utils/src/main/java/org/owasp/dependencycheck/utils/FileUtils.java b/dependency-check-utils/src/main/java/org/owasp/dependencycheck/utils/FileUtils.java
index <HASH>..<HASH> 100644
--- a/dependency-check-utils/src/main/java/org/owasp/dependencycheck/utils/FileUtils.java
+++ b/dependency-check-utils/src/main/java/org/owasp/dependencycheck/utils/FileUtils.java
@@ -60,7 +60,7 @@ public final class FileUtils {
      */
     public static String getFileExtension(String fileName) {
         final String fileExt = FilenameUtils.getExtension(fileName);
-        return null != fileExt ? fileExt.toLowerCase() : null;
+        return null == fileExt || fileExt.isEmpty() ? null : fileExt.toLowerCase();
     }
 
     /**
Demonstrating the benefit of commons-io instead of the simpler string dissection.