diff --git a/packages/binding-http/src/http-server.ts b/packages/binding-http/src/http-server.ts
index d8c00b536..60aed833b 100644
--- a/packages/binding-http/src/http-server.ts
+++ b/packages/binding-http/src/http-server.ts
@@ -307,9 +307,8 @@ export default class HttpServer implements ProtocolServer {
 
     private addUrlRewriteEndpoints(form: TD.Form, forms: Array<TD.Form>): void {
         if (this.urlRewrite) {
-            for (const inUri in this.urlRewrite) {
-                const toUri = this.urlRewrite[inUri];
-                if (form.href.endsWith(toUri)) {
+            for (const [inUri, toUri] of Object.entries(this.urlRewrite)) {
+                if (toUri != null && form.href.endsWith(toUri)) {
                     const form2: TD.Form = JSON.parse(JSON.stringify(form)); // deep copy
                     form2.href = form2.href.substring(0, form.href.lastIndexOf(toUri)) + inUri;
                     forms.push(form2);