CSRF, Token and Same-Origin Policy explained - cookies

So I know there are a lot of questions about CSRF (because I have read some of them) but there is one point I still don't understand. Let's imagine the following case:
I am logged in(with cookies) on my server where there is a page with a button 'Delete my account'. Which I don't want to press.
I visit a hacker's server:
a. My browser requests 'bad.html', which contains JS, with a callback function defined. It also has a script like:(thus avoiding the Same-Origin Policy problem)
var s = document.createElement('script');
s.src = 'url to "deleteAccountPage" of my server?'
s.src += 'callback=hackerCallback';
s.type = 'text/javascript';
document.body.appendChild(s);
b. Script is "appended" the browser will load the page and then call hackerCallback passing the page HTML text as parameter.
c. With this HTML, the callback can parse the token in there.
The hackerCallback now has the token, sends an Ajax request to my server on the "deleteMyAccount" page.
My account is now deleted, because the Token, the cookies and even the browser trace matches the ones registered by the server.
How do you avoid that behaviour ? I have read things about only allowing certain Headers on my server. This would cut short all Cross-Domain request on my server, however according to this link (http://blog.alexmaccaw.com/jswebapps-csrf) it is not enough... (Which I totally believe)
Thansk for the help
Seba-1511

You are using JSONP in order to make a cross domain request via a scr tag. The JSONP is only allowed for GET requests and you shouldn't have GET endpoints that make changes (not idempotent).
deleteAccount should be a POST endpoint that couldn't be requested via JSONP.
If you insist in use GET on deleteAccount you should use CSRF tokens or send the token in a header instead of a cookie (if you're using XHR requests)

Related

JMeter 5.4.1 Cookie Manager - User-Defined Cookie not added to request's cookies

Firstly, I did add the line CookieManager.check.cookies=false to jmeter.properties.
What I'm Trying to Do
I want to add a cookie to a request's existing cookies.
For example, I see the request has [edited]:
Cookie Data:
c1=sfasfsfsfsfs; c2=erqwerqwrr; c3=poiuopiupoi
Expected Results
I would like it to have:
Cookie Data:
c1=sfasfsfsfsfs; c2=erqwerqwrr; c3=poiuopiupoi; partner=favicon.ico
Here is what I tried:
BASE_URL_2 is a variable defined in the form qa.company.com.
Actual Results
Whatever I have tried so far has not made any change in the cookies.
What else shall I try?
Underlying Motivation
Recorded a Web session and played it back.
Added a RegEx Extractor to pull out a token and then added it to subsequent requests. That helped.
However, certain requests failed with an custom application exception Security violation, please refresh.
Probably session login state is not being passed, so the website thinks the call is "stale".
I've seen this on the GUI when the session expires and you try to click a button on the site.
On comparing the cookies seem in JMeter with what I saw in the Chrome Debugger, it was clear that there were more cookies in the running application than what I had in JMeter.
Are you sure you're using HTTPS protocol because if you have secure flag and using HTTP protocol - the cookie will not be sent.
Also remove = from partner= otherwise you will end up with partner==favicon.ico
Demo:
More information:
Using HTTP cookies
HTTP Cookie Manager Advanced Usage - A Guide

Why cookies appear in request header but not response header when visiting a new website?

This is a incognito window in chrome visiting oracle. Please notice that the request header already has cookie in the very request.
I also tried to use GuzzleHttp in php and postman. I can't get the cookie from anywhere.
Actually I am trying to crawl some other website, and that website has the same problem. I can't get the cookie so I got rejected.
Isn't cookie something that the server returns to the browser? Why in this case it is like the browse know the cookie in the first?
Http cookies are set once in a response by the server (with a Set-Cookie header), then they are included by the browser in each applicable subsequent request.
So it is perfectly normal that cookies your browser already obtained are present in the request but not in the response.
Cookies may also be set on browser side by Javascript, but that also can't happen before the first request (to at least retrieve that Javascript).

send a cookie with XMLHTTPRequest (TVMLJS)

I am developing an application for my AppleTV. The App will read movies from an online website that hasn't developed any API for this kind of thing.
I use XMLHTTPRequest to get the different URLs and have the user search for his movie, etc... Everything is working fine, except for a single request. To get the movie URL, I have to send a get request to a specific address (let's say http://example.com/getmovie.html) with a constant cookie (let's say mycookie=cookie).
I've tried using setRequestHeader:
var xhr = new XMLHttpRequest();
xhr.open("GET", url, false);
xhr.withCredentials = true;
xhr.setRequestHeader('Cookie', 'mycookie=cookie');
xhr.send();
But no cookie seems to be sent.
I also tried setting the cookie with Document.cookie like I would have probably done in a "normal" js script (running in my browser) but no luck either.
This is extremely frustrating, especially since I'm stuck so close to the end of my app.
I guess cross-origin might be the issue but I'm able to get URLs without issues if I don't have to set cookies, so I am a bit lost there.
Please let me know how I can get http://example.com/getmovie.html with a specific cookie header.
Thanks for your help
im sorry to inform you but the xmlHTTPRequest function of javascript does not allow a cookie header to be set for security reasons as shown here: Why cookies and set-cookie headers can't be set while making xmlhttprequest using setRequestHeader? the best way i could see you making that get request would be to a proxy server that you would be running. I believe that it is built this way to prevent you from setting cookies on domains that you do not own, furthermore i do not see an alternate resolution to this problem as no were in the docs i looked at was cookie persistence or management mentioned
In case someone has the same issue:
I didn't find a solution to sending a cookie with javascript. However, in my situation, the origin of the request didn't matter, only the cookie did. My solution was then to create a PHP file receiving the destination URL and the cookie content as parameters, and then sending the get request with the cookie as a request header. (more information about how to do so here: PHP GET Request, sending headers).
In my javascript I then use XMLHttpRequest to connect to my PHP file (hosted online) with simple get parameters and I then receive the response from the PHP. That trick of course won't work if the origin of the request matters (except if you host your file at home I guess, but in my case I want my application to work even if my WAMP isn't on).
Well... the problem here is the line xhr.setRequestHeader('Cookie', 'mycookie=cookie'); line just because the 'Cookie' header is reserved for the client browser to send the stored cookies. This means you are trying to do what the browser already does. When you send a any request, the client browser automatlycally will take all the cookies related to the site you are requesting and put them on the 'Cookie' header, you don't need to do anything else, if your cookie exist in your browser, it will be send.
Cordova how to send session cookie, allow credentials with XMLhttprequest:
// JS
var xhr = new XMLHttpRequest();
xhr.open('GET', 'http://example.com/ajax.php', true);
xhr.withCredentials = true;
xhr.onreadystatechange = function() {
if(xhr.readyState == 4 && xhr.status == 200) {
// alert(xhr.responseText);
// Get header from php server request if you want for something
var cookie = xhr.getResponseHeader("Cookie");
// alert("Cookie: " + cookie);
}
}
xhr.send();
// Php
// You can add cookie to header and get with (session works without it)
header('Cookie: PHPSESSID='.$_COOKIE['PHPSESSID']);
header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: GET, POST, OPTIONS');
header('Access-Control-Allow-Headers: Origin, Content-Type, Accept, Authorization, X-Request-With, Set-Cookie, Cookie, Bearer');
header('Access-Control-Allow-Credentials: true');
header('Access-Control-Max-Age: 86400');

Set-Cookie for a login system

I've run into a few problems with setting cookies, and based on the reading I've done, this should work, so I'm probably missing something important.
This situation:
Previously I received responses from my API and used JavaScript to save them as cookies, but then I found that using the set-cookie response header is more secure in a lot of situations.
I have 2 cookies: "nuser" (contains a username) and key (contains a session key). nuser shouldn't be httpOnly so that JavaScript can access it. Key should be httpOnly to prevent rogue scripts from stealing a user's session. Also, any request from the client to my API should contain the cookies.
The log-in request
Here's my current implementation: I make a request to my login api at localhost:8080/login/login (keep in mind that the web-client is hosted on localhost:80, but based on what I've read, port numbers shouldn't matter for cookies)
First the web-browser will make an OPTIONS request to confirm that all the headers are allowed. I've made sure that the server response includes access-control-allow-credentials to alert the browser that it's okay to store cookies.
Once it's received the OPTIONS request, the browser makes the actual POST request to the login API. It sends back the set-cookie header and everything looks good at this point.
The Problems
This set-up yields 2 problems. Firstly, though the nuser cookie is not httpOnly, I don't seem to be able to access it via JavaScript. I'm able to see nuser in my browser's cookie option menu, but document.cookie yeilds "".
Secondly, the browser seems to only place the Cookie request header in requests to the exact same API (the login API):
But, if I do a request to a different API that's still on my localhost server, the cookie header isn't present:
Oh, and this returns a 406 just because my server is currently configured to do that if the user isn't validated. I know that this should probably be 403, but the thing to focus on in this image is the fact that the "cookie" header isn't included among the request headers.
So, I've explained my implementation based on my current understanding of cookies, but I'm obviously missing something. Posting exactly what the request and response headers should look like for each task would be greatly appreciated. Thanks.
Okay, still not exactly what was causing the problem with this specific case, but I updated my localhost:80 server to accept api requests, then do a subsequent request to localhost:8080 to get the proper information. Because the set-cookie header is being set by localhost:80 (the client's origin), everything worked fine. From my reading before, I thought that ports didn't matter, but apparently they do.

question about cookie

I'm stuck in a cookie related question. I want to write a program that can automate download the attachments of this forum. So I should maintain the cookies this site send to me. When I send a GET request in my program to the login page, I got the cookie such as Set-Cookie: sso_sid=0589a967; domain=.it168.com in my program. Now if I use a cookie viewer such as cookie monster and send the same GET request, my program get the same result, but the cookie viewer shows that the site also send me two cookies which are:
testcookie http://get2know.it/myimages/2009-12-27_072438.jpg and token http://get2know.it/myimages/2009-12-27_072442.jpg
My question is: Where did the two cookie came from? Why they did not show in my program?
Thanks.
Your best bet to figure out screen-scraping problems like this one is to use Fiddler. Using Fiddler, you can compare exactly what is going over the wire in your app vs. when accessing the site from a browser. I suspect you'll see some difference between headers sent by your app vs. headers sent by the browser-- this will likley account for the difference you're seeing.
Next, you can do one of two things:
change your app to send exactly the headers that the browser does (and, if you do this, you should get exactly the response that a real browser gets).
using Fiddler's "request builder" feature, start removing headers one by one and re-issuing the request. At some point, you'll remove a header which makes the response not match the response you're looking for. That means that header is required. Continue for all other headers until you have a list of headers that are required by the site to yield the response you want.
Personally, I like option #2 since it requires a minimum amount of header-setting code, although it's harder initially to figure out which headers the site requires.
On your actual question of why you're seeing 2 cookies, only the diagnosis above will tell you for sure, but I suspect it may have to do with the mechanism that some sites use to detect clients who don't accept cookies. On the first request in a session, many sites will "probe" a client to see if the client accepts cookies. Typically they'll do this:
if the request doesn't have a cookie on it, the site will redirect the client to a special "cookie setting" URL.
The redirect response, in addition to having a Location: header which does the redirect, will also return a Set-Cookie header to set the cookie. The redirect will typically contain the original URL as a query string parameter.
The server-side handler for the "cookie setter" page will then look at the incoming cookie. If it's blank, this means that the user's browser is set to not accept cookies, and the site will typically redirect the user to a "sorry, you must use cookies to use this site" page.
If, however, there is a cookie header send to the "cookie setter" URL, then the client does in fact accept cookies, and the handler will simply redirect the client back to the original URL.
The original URL, once you move on to the next page, may add an additional cookie (e.g. for a login token).
Anyway, that's one way you could end up with two cookies. Only diagnosis with Fiddler (or a similar tool) will tell you for sure, though.