diff --git a/cli/tests/unit_node/http_test.ts b/cli/tests/unit_node/http_test.ts
index 91e2f57030edc5..3573416f83b5a7 100644
--- a/cli/tests/unit_node/http_test.ts
+++ b/cli/tests/unit_node/http_test.ts
@@ -716,7 +716,9 @@ Deno.test(
     });
     // @ts-ignore it's a socket for real
     let serverSocket;
-    server.on("upgrade", (_req, socket, _head) => {
+    server.on("upgrade", (req, socket, _head) => {
+      // https://github.com/denoland/deno/issues/21979
+      assert(req.socket?.write);
       socket.write(
         "HTTP/1.1 101 Web Socket Protocol Handshake\r\n" +
           "Upgrade: WebSocket\r\n" +
diff --git a/ext/node/polyfills/http.ts b/ext/node/polyfills/http.ts
index fe589653447244..9356dde0ad5864 100644
--- a/ext/node/polyfills/http.ts
+++ b/ext/node/polyfills/http.ts
@@ -1637,6 +1637,8 @@ export class ServerImpl extends EventEmitter {
         const socket = new Socket({
           handle: new TCP(constants.SERVER, conn),
         });
+        // Update socket held by `req`.
+        req.socket = socket;
         this.emit("upgrade", req, socket, Buffer.from([]));
         return response;
       } else {