diff --git a/server/middleware/utils/createMutex.js b/server/middleware/utils/createMutex.js
index 9be3687..a83dd23 100644
--- a/server/middleware/utils/createMutex.js
+++ b/server/middleware/utils/createMutex.js
@@ -1,5 +1,5 @@
 function createMutex(doWork) {
-  const mutex = {};
+  const mutex = Object.create(null);
 
   return (key, payload, callback) => {
     if (mutex[key]) {