diff --git a/lib/SimpleSAML/Store/SQL.php b/lib/SimpleSAML/Store/SQL.php
index 7b837c0644b1e1cd68e5029471f14b456e3ca3c8..85fd4245b3e05832fb9fcd96a46f8def5a5a6caa 100644
--- a/lib/SimpleSAML/Store/SQL.php
+++ b/lib/SimpleSAML/Store/SQL.php
@@ -252,6 +252,10 @@ class SimpleSAML_Store_SQL extends SimpleSAML_Store {
 		}
 		$value = urldecode($value);
 		$value = unserialize($value);
+
+                if ($value === FALSE) {
+                    return NULL;
+                }
 		return $value;
 	}