CODEWITHSUNDEEP
security
bigpotato
bigpotato

Reputation: 27557

Web security: What prevents a hacker from spoofing a bank's site and grabbing data before form submission? (with example)

  1. Assume http://chaseonline.chase.com is a real URL with a web server sitting behind it, i,e, this URL revolves to an IP address or probably several so that there can be a lot of identical servers that allows load balancing from client requests.

  2. I guess that probably Chase buys up URLs that are "close" in the URL namespace(<<< how to define the term "namespace"? Lexicographically?? I think the latter is not trivial (because it depends on a post that one defines on top of URL strings ... never mind this comment).

  3. Suppose that given of the URLs (http://mychaseonline.chase.com, http://chaseonline.chase.ua, http://chaseonline.chase.ru, etc.) is "free" (not bought). I buy one of these free URLs, write my phishing/spoofing server that sits behind my URL and renders the following screen => https://chaseonline.chase.com/

  4. I work to get my URL indexed (hopefully) at least as high or higher than the real one (http://chaseonline.chase.com). Chance is (hopefully) most bank clients/users won't notice my bogus URLs and I start collecting . I then use my server as a client in relationship to the real bank server http://chaseonline.chase.com, log in and using my collection/list of <user id, password> tuples to login to each <user id, password> to create mischief.

Is this a cross-site request forgery? How would one prevent this from occurring?

Upvotes: 2

Views: 180

Answers (2)

MSalters
MSalters

Reputation: 180295

There's nothing cross-site about this. It's a simple forgery.

It fails for a number of reasons: lack of security (your site isn't HTTPS), malware protection vendors explicitly check against this kind of abuse, Google won't rank your forgery above highly popular sites, and finally banks with a real sense of security use 2 Factor Authentication. The login token you'd get for my bank account is valid for a few seconds, literally, and can't be used for anything but logging in.

Upvotes: 2

Gavin Miller
Gavin Miller

Reputation: 43875

What I'm hearing in your description is a phishing attack albeit with slightly more complexity. Let's address some of this points

2) Really hard to get all the urls, especially when you take into consideration different variations such as unicode, or even just simple kerning hacks. For example the R and N in kerning looks a lot like an m when you look quickly. Welcome to chаse.rnobile.com! So with that said, I'd guess that most companies just buy the obvious domains.

4) Getting your url indexed higher than the real one, I'll posit is impossible. Google et al. are likely sophisticated enough to catch that type of thing from happening. One approach to getting above chase in SERP would be to buy adwords for something like "Bank Online With Chase." But there again, I'd assume that the search engines have a decent filtering/fraud prevention mechanism to catch this type of thing.

Mostly you'd be better off to keep your server from being indexed since that would simply attract attention. Because this type of thing will be shut down, I presume most phishing attacks go for large numbers of small 'fish' (larger ROI) or small numbers of large 'fish' (think targeted phishing attacks of execs, bank employees, etc.)

I think you offer up an interesting idea in point 4, that there's nothing to stop a man-in-the-middle attack from occurring wherein your site delegates out to the target site for each request. The difficulty in that approach is that you'd spend a ton of resources on creating a replica website. When you think of most hacking as being a business, trying to maximize your ROI then a lot of the "this is what I'd do if I were a hacker" ideas go way.

If I were to do this type of thing, I'd provide a login facade, have the user provide me their credentials, and then redirect to the main site on POST to my server. This way I get your credentials and you think there's just been an error on the form. I'm then free to pull all the information off of your banking site at my leisure.

Upvotes: 2

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