Fix rapid7#9307, credit to @r0610205

Author: wvu

modules/exploits/multi/http/bassmaster_js_injection.rb

@@ -124,7 +124,7 @@ def send_payload
       return true
 
     # incase we are not targeting the default app
-    elsif res and res.code == 500 and es.body !=~ /id/
+    elsif res and res.code == 500 and res.body !=~ /id/
       return true
     end
     return false