diff --git a/Step/Attributes/WebApiAuthorizeAttribute.cs b/Step/Attributes/WebApiAuthorizeAttribute.cs
index fc41d4b9..f8a71b45 100644
--- a/Step/Attributes/WebApiAuthorizeAttribute.cs
+++ b/Step/Attributes/WebApiAuthorizeAttribute.cs
@@ -22,6 +22,9 @@ namespace Step
         protected override bool IsAuthorized(HttpActionContext actionContext)
         {
             // Get token from headers
+            if (actionContext.Request.Headers.Authorization == null)
+                return false;
+
             string token = actionContext.Request.Headers.Authorization.ToString();