2 files changed, 8 insertions, 0 deletions
diff --git a/src/main/java/com/it_jaros/jscanner/CliDefaults.java b/src/main/java/com/it_jaros/jscanner/CliDefaults.java
index d521851..9331c29 100644
--- a/src/main/java/com/it_jaros/jscanner/CliDefaults.java
+++ b/src/main/java/com/it_jaros/jscanner/CliDefaults.java
@@ -1,6 +1,10 @@
 package com.it_jaros.jscanner;
 
 public class CliDefaults {
+    private CliDefaults() {
+        /* This utility class should not be instantiated */
+    }
+
     public static final String PORTS = "1-1024";
     public static final boolean BANNER_RECOGNITION = false;
     public static final boolean DISABLE_HOST_CHECK = false;
diff --git a/src/main/java/com/it_jaros/jscanner/Scanner.java b/src/main/java/com/it_jaros/jscanner/Scanner.java
index d44a4b0..7aeee03 100644
--- a/src/main/java/com/it_jaros/jscanner/Scanner.java
+++ b/src/main/java/com/it_jaros/jscanner/Scanner.java
@@ -83,6 +83,10 @@ public class Scanner implements AutoCloseable {
     }
 
     public List<ScanResult> runScan(Scan scan) {
+        if (scan == null) {
+            throw new IllegalArgumentException("Scan argument cannot be null");
+        }
+
         ScanState scanState = scan.state();
         scanState.getProgressBar().start();
         try (ExecutorService executor = Executors.newVirtualThreadPerTaskExecutor()) {