diff --git a/lib/browser.js b/lib/browser.js
index e7debfb..652dc0c 100644
--- a/lib/browser.js
+++ b/lib/browser.js
@@ -222,8 +222,11 @@ exports.encodeBase64Packet = function(packet, callback) {
  */
 
 exports.decodePacket = function (data, binaryType, utf8decode) {
+  if (data === undefined) {
+    return err;
+  }
   // String data
-  if (typeof data == 'string' || data === undefined) {
+  if (typeof data == 'string') {
     if (data.charAt(0) == 'b') {
       return exports.decodeBase64Packet(data.substr(1), binaryType);
     }
diff --git a/lib/index.js b/lib/index.js
index e9dafd9..716b1d5 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -118,8 +118,11 @@ exports.encodeBase64Packet = function(packet, callback){
  */
 
 exports.decodePacket = function (data, binaryType, utf8decode) {
+  if (data === undefined) {
+    return err;
+  }
   // String data
-  if (typeof data == 'string' || data === undefined) {
+  if (typeof data == 'string') {
     if (data.charAt(0) == 'b') {
       return exports.decodeBase64Packet(data.substr(1), binaryType);
     }
diff --git a/test/parser.js b/test/parser.js
index da852d8..9a19394 100644
--- a/test/parser.js
+++ b/test/parser.js
@@ -129,6 +129,10 @@ module.exports = function(parser) {
       describe('decoding error handing', function () {
         var err = { type: 'error', data: 'parser error' };
 
+        it('should disallow empty payload', function () {
+          expect(decode(undefined)).to.eql(err);
+        });
+
         it('should disallow bad format', function () {
           expect(decode(':::')).to.eql(err);
         });