diff --git a/src/main/java/com/hierynomus/ntlm/functions/NtlmFunctions.java b/src/main/java/com/hierynomus/ntlm/functions/NtlmFunctions.java
index 64c8d806..d9374ffd 100644
--- a/src/main/java/com/hierynomus/ntlm/functions/NtlmFunctions.java
+++ b/src/main/java/com/hierynomus/ntlm/functions/NtlmFunctions.java
@@ -192,7 +192,9 @@ public byte[] getNTLMv2ClientChallenge(TargetInfo targetInformation) {
         ccBuf.putLong(nowAsFileTime); // Timestamp (8)
         ccBuf.putRawBytes(challengeFromClient); // ChallengeFromClient (8)
         ccBuf.putUInt32(0); // Reserved3 (4)
-        targetInformation.writeTo(ccBuf); // AvPairs (variable)
+        if (targetInformation != null) {
+            targetInformation.writeTo(ccBuf); // AvPairs (variable)
+        }
         ccBuf.putUInt32(0); // Last AV Pair indicator
 
         return ccBuf.getCompactData();
diff --git a/src/main/java/com/hierynomus/ntlm/messages/NtlmAuthenticate.java b/src/main/java/com/hierynomus/ntlm/messages/NtlmAuthenticate.java
index 983be829..e5222f28 100644
--- a/src/main/java/com/hierynomus/ntlm/messages/NtlmAuthenticate.java
+++ b/src/main/java/com/hierynomus/ntlm/messages/NtlmAuthenticate.java
@@ -124,12 +124,12 @@ public byte[] getVersion() {
         return plainBuffer.getCompactData();
     }
 
-    private int writeOffsettedByteArrayFields(Buffer.PlainBuffer buffer, byte[] array, int offset) {
-        byte[] _array = array != null ? array : EMPTY;
-        buffer.putUInt16(_array.length); // ArrayLen
-        buffer.putUInt16(_array.length); // ArrayMaxLen
+    private int writeOffsettedByteArrayFields(Buffer.PlainBuffer buffer, byte[] bytes, int offset) {
+        byte[] arr = bytes != null ? bytes : EMPTY;
+        buffer.putUInt16(arr.length); // ArrayLen
+        buffer.putUInt16(arr.length); // ArrayMaxLen
         buffer.putUInt32(offset); // ArrayOffset
-        return offset + _array.length;
+        return offset + arr.length;
     }
 
     private byte[] ensureNotNull(byte[] possiblyNull) {