diff --git a/lib/socket.ts b/lib/socket.ts
index 4005462b4..dbcb9285c 100644
--- a/lib/socket.ts
+++ b/lib/socket.ts
@@ -250,7 +250,10 @@ export class Socket extends Emitter {
         break;
 
       case PacketType.CONNECT_ERROR:
-        super.emit("connect_error", packet.data);
+        const err = new Error(packet.data.message);
+        // @ts-ignore
+        err.data = packet.data.data;
+        super.emit("connect_error", err);
         break;
     }
   }
diff --git a/test/socket.ts b/test/socket.ts
index 8a1e44b3b..b27be71d5 100644
--- a/test/socket.ts
+++ b/test/socket.ts
@@ -177,7 +177,8 @@ describe("socket", function () {
   it("should fire an error event on middleware failure from custom namespace", (done) => {
     const socket = io("/no", { forceNew: true });
     socket.on("connect_error", (err) => {
-      expect(err).to.eql("Auth failed (custom namespace)");
+      expect(err).to.be.an(Error);
+      expect(err.message).to.eql("Auth failed (custom namespace)");
       socket.disconnect();
       done();
     });