140
votes

How to share cookies cross origin? More specifically, how to use the Set-Cookie header in combination with the header Access-Control-Allow-Origin?

Here's an explanation of my situation:

I am attempting to set a cookie for an API that is running on localhost:4000 in a web app that is hosted on localhost:3000.

It seems I'm receiving the right response headers in the browser, but unfortunately they have no effect. These are the response headers:

HTTP/1.1 200 OK
Access-Control-Allow-Origin: http://localhost:3000
Vary: Origin, Accept-Encoding
Set-Cookie: token=0d522ba17e130d6d19eb9c25b7ac58387b798639f81ffe75bd449afbc3cc715d6b038e426adeac3316f0511dc7fae3f7; Max-Age=86400; Domain=localhost:4000; Path=/; Expires=Tue, 19 Sep 2017 21:11:36 GMT; HttpOnly
Content-Type: application/json; charset=utf-8
Content-Length: 180
ETag: W/"b4-VNrmF4xNeHGeLrGehNZTQNwAaUQ"
Date: Mon, 18 Sep 2017 21:11:36 GMT
Connection: keep-alive

Furthermore, I can see the cookie under Response Cookies when I inspect the traffic using the Network tab of Chrome's developer tools. Yet, I can't see a cookie being set in in the Application tab under Storage/Cookies. I don't see any CORS errors, so I assume I'm missing something else.

Any suggestions?

Update I:

I'm using the request module in a React-Redux app to issue a request to a /signin endpoint on the server. For the server I use express.

Express server:

res.cookie('token', 'xxx-xxx-xxx', { maxAge: 86400000, httpOnly: true, domain: 'localhost:3000' })

Request in browser:

request.post({ uri: '/signin', json: { userName: 'userOne', password: '123456'}}, (err, response, body) => {
    // doing stuff
})

Update II:

I am setting request and response headers now like crazy now, making sure that they are present in both the request and the response. Below is a screenshot. Notice the headers Access-Control-Allow-Credentials, Access-Control-Allow-Headers, Access-Control-Allow-Methods and Access-Control-Allow-Origin. Looking at the issue I found at Axios's github, I'm under the impression that all required headers are now set. Yet, there's still no luck...

enter image description here

6
@PimHeijden take a look to this: developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest/… maybe the use of withCredentials is what you need?Kalamarico
Ok you are using request and i think this is not the best choice, take a look to this post and the answer, axios i think could be usefull to you. stackoverflow.com/questions/39794895/…Kalamarico
Thanks! I failed to notice that the request module is not meant for use in the browser. Axios seems to do a great job so far. I receive now both the header: Access-Control-Allow-Credentials:true and Access-Control-Allow-Origin:http://localhost:3000 (used to enable CORS). This seems right but the Set-Cookie header doesnt do anything...Pim Heijden
Same issue, but using directly Axios : stackoverflow.com/q/43002444/488666. While { withCredentials: true } is indeed required by Axios side, server headers have to be checked carefully as well (see stackoverflow.com/a/48231372/488666)Frosty Z
what server headers?Pim Heijden

6 Answers

219
votes

What you need to do

To allow receiving & sending cookies by a CORS request successfully, do the following.

Back-end (server): Set the HTTP header Access-Control-Allow-Credentials value to true. Also, make sure the HTTP headers Access-Control-Allow-Origin and Access-Control-Allow-Headers are set and not with a wildcard *.

Recommended Cookie settings per Chrome and Firefox update in 2021: SameSite=None and Secure. See MDN documentation

For more info on setting CORS in express js read the docs here

Front-end (client): Set the XMLHttpRequest.withCredentials flag to true, this can be achieved in different ways depending on the request-response library used:

Or

Avoid having to use CORS in combination with cookies. You can achieve this with a proxy.

If you for whatever reason don't avoid it. The solution is above.

It turned out that Chrome won't set the cookie if the domain contains a port. Setting it for localhost (without port) is not a problem. Many thanks to Erwin for this tip!

29
votes

Note for Chrome Browser released in 2020.

A future release of Chrome will only deliver cookies with cross-site requests if they are set with SameSite=None and Secure.

So if your backend server does not set SameSite=None, Chrome will use SameSite=Lax by default and will not use this cookie with { withCredentials: true } requests.

More info https://www.chromium.org/updates/same-site.

Firefox and Edge developers also want to release this feature in the future.

Spec found here: https://tools.ietf.org/html/draft-west-cookie-incrementalism-01#page-8

11
votes

In order for the client to be able to read cookies from cross-origin requests, you need to have:

  1. All responses from the server need to have the following in their header:

    Access-Control-Allow-Credentials: true

  2. The client needs to send all requests with withCredentials: true option

In my implementation with Angular 7 and Spring Boot, I achieved that with the following:


Server-side:

@CrossOrigin(origins = "http://my-cross-origin-url.com", allowCredentials = "true")
@Controller
@RequestMapping(path = "/something")
public class SomethingController {
  ...
}

The origins = "http://my-cross-origin-url.com" part will add Access-Control-Allow-Origin: http://my-cross-origin-url.com to every server's response header

The allowCredentials = "true" part will add Access-Control-Allow-Credentials: true to every server's response header, which is what we need in order for the client to read the cookies


Client-side:

import { HttpInterceptor, HttpXsrfTokenExtractor, HttpRequest, HttpHandler, HttpEvent } from "@angular/common/http";
import { Injectable } from "@angular/core";
import { Observable } from 'rxjs';

@Injectable()
export class CustomHttpInterceptor implements HttpInterceptor {

    constructor(private tokenExtractor: HttpXsrfTokenExtractor) {
    }

    intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
        // send request with credential options in order to be able to read cross-origin cookies
        req = req.clone({ withCredentials: true });

        // return XSRF-TOKEN in each request's header (anti-CSRF security)
        const headerName = 'X-XSRF-TOKEN';
        let token = this.tokenExtractor.getToken() as string;
        if (token !== null && !req.headers.has(headerName)) {
            req = req.clone({ headers: req.headers.set(headerName, token) });
        }
        return next.handle(req);
    }
}

With this class you actually inject additional stuff to all your request.

The first part req = req.clone({ withCredentials: true });, is what you need in order to send each request with withCredentials: true option. This practically means that an OPTION request will be send first, so that you get your cookies and the authorization token among them, before sending the actual POST/PUT/DELETE requests, which need this token attached to them (in the header), in order for the server to verify and execute the request.

The second part is the one that specifically handles an anti-CSRF token for all requests. Reads it from the cookie when needed and writes it in the header of every request.

The desired result is something like this:

response request

4
votes

For express, upgrade your express library to 4.17.1 which is the latest stable version. Then;

In CorsOption: Set origin to your localhost url or your frontend production url and credentials to true e.g

  const corsOptions = {
    origin: config.get("origin"),
    credentials: true,
  };

I set my origin dynamically using config npm module.

Then , in res.cookie:

For localhost: you do not need to set sameSite and secure option at all, you can set httpOnly to true for http cookie to prevent XSS attack and other useful options depending on your use case.

For production environment, you need to set sameSite to none for cross-origin request and secure to true. Remember sameSite works with express latest version only as at now and latest chrome version only set cookie over https, thus the need for secure option.

Here is how I made mine dynamic

 res
    .cookie("access_token", token, {
      httpOnly: true,
      sameSite: app.get("env") === "development" ? true : "none",
      secure: app.get("env") === "development" ? false : true,
    })
2
votes

Pim's answer is very helpful. In my case, I have to use

Expires / Max-Age: "Session"

If it is a dateTime, even it is not expired, it still won't send the cookie to the backend:

Expires / Max-Age: "Thu, 21 May 2020 09:00:34 GMT"

Hope it is helpful for future people who may meet same issue.

0
votes
  1. frontend

    `await axios.post(`your api`, data,{
        withCredentials:true,
    })
    await axios.get(`your api`,{
            withCredentials:true,
        });`
    
  2. backend

    var  corsOptions  = {
     origin: 'http://localhost:3000', //frontend url
     credentials: true}
    
    
    app.use(cors(corsOptions));
    const token=jwt.sign({_id:user_id},process.env.JWT_SECRET,{expiresIn:"7d"});
    res.cookie("token",token,{httpOnly:true});
    
    
    
    hope it will work.