diff --git a/lib/attribute.js b/lib/attribute.js
index ed169fb..5a75217 100644
--- a/lib/attribute.js
+++ b/lib/attribute.js
@@ -71,12 +71,12 @@ Attribute.prototype.parse = function(ber) {
   ber.readSequence();
   this.type = ber.readString().toLowerCase();
 
-
-  if (ber.readSequence(Protocol.LBER_SET)) {
-    var end = ber.offset + ber.length;
-    while (ber.offset < end)
-      this.vals.push(ber.readString());
-
+  if (ber.peek() === Protocol.LBER_SET) {
+    if (ber.readSequence(Protocol.LBER_SET)) {
+      var end = ber.offset + ber.length;
+      while (ber.offset < end)
+        this.vals.push(ber.readString());
+    }
   }
 
   return true;