diff --git a/src/main/java/the/bytecode/club/bytecodeviewer/util/MiscUtils.java b/src/main/java/the/bytecode/club/bytecodeviewer/util/MiscUtils.java
index 8a5ea56b..3fb628c1 100644
--- a/src/main/java/the/bytecode/club/bytecodeviewer/util/MiscUtils.java
+++ b/src/main/java/the/bytecode/club/bytecodeviewer/util/MiscUtils.java
@@ -163,6 +163,9 @@ public class MiscUtils
 
     public static String getFileHeaderMagicNumber(byte[] fileContents)
     {
+        if(fileContents == null || fileContents.length < 4)
+            return StringUtils.EMPTY;
+        
         return String.format("%02X%02X%02X%02X", fileContents[0],
                 fileContents[1], fileContents[2],fileContents[3]);
     }