diff --git a/lib/SAML2/Assertion.php b/lib/SAML2/Assertion.php
index 571a74d1d078f92a95caba697c37dfbe854e1857..630a60abf4dc23fc85f5acc92eacc4ddebf173fa 100644
--- a/lib/SAML2/Assertion.php
+++ b/lib/SAML2/Assertion.php
@@ -663,6 +663,8 @@ class SAML2_Assertion implements SAML2_SignedElement {
 
 
 	public function decryptAttributes($key, array $blacklist = array()){
+		$firstAttribute = TRUE;
+
 		if($this->encryptedAttribute === null){
 			return;
 		}