I tend to have just a browser window open, with many and many tabs (once they summed up to 27…) without any particular order, and the last phishing like technique is scaring me.

You know, the bad guys are always scratching their heads to find new way to hurt the good guys. Their new trick has been called “nabtabbing” and it is a sort of improved or revisited phishing technique.

From Azarask:

How The Attack Works

1. A user navigates to your normal looking site.
2. You detect when the page has lost its focus and hasn’t been interacted with for a while.
3. Replace the favicon with the Gmail favicon, the title with “Gmail: Email from Google”, and the page with a Gmail login look-a-like. This can all be done with just a little bit of Javascript that takes place instantly.
4. As the user scans their many open tabs, the favicon and title act as a strong visual cue—memory is malleable and moldable and the user will most likely simply think they left a Gmail tab open. When they click back to the fake Gmail tab, they’ll see the standard Gmail login page, assume they’ve been logged out, and provide their credentials to log in. The attack preys on the perceived immutability of tabs.
5. After the user has entered their login information and you’ve sent it back to your server, you redirect them to Gmail. Because they were never logged out in the first place, it will appear as if the login was successful.

We’ll call this new type of phishing attack “tabnabbing“.

Targeted Attacks

There are many ways to potentially improve the efficacy of this attack.

Using my CSS history miner you can detect which site a visitor uses and then attack that site (although this is no longer possible in Firefox betas). For example, you can detect if a visitor is a Facebook user, Citibank user, Twitter user, etc., and then switch the page to the appropriate login screen and favicon on demand.

Even more deviously, there are various methods to know whether a user is currently logged into a service. These methods range from timing attacks on image loads, to seeing where errors occur when you load an HTML webpage in a script tag*. Once you know what services a user is currently logged in to, the attack becomes even more effective.

[*] Think looking for the exact error thrown when embedding <script src=”http://gmail.com”/> it will be differ depending on if the user is logged in or logged out.

You can make this attack even more effective by changing the copy: Instead of having just a login screen, you can mention that the session has timed out and the user needs to re-authenticate. This happens often on bank websites, which makes them even more susceptible to this kind of attack.



Attack Vector

Every time you include a third-party script on your page, or a Flash widget, you leave yourself wide open for an evil doer to use your website as a staging ground for this kind of attack. If you are the evil doer, you can have this behavior only occur once in a while, and only if the user uses a targeted service. In other words, it could be hard to detect.

You can also use a cross-site scripting vulnerabilities to force the attack to be performed by other websites. And for browsers that do not support changing the favicon, you can use a location.assign call to navigate the page to a controlled domain with the correct favicon. As long as the user wasn’t looking at the tab when the refresh occurred (which they won’t be), they’ll have no idea what hit them. Combine this with look-alike Unicode domain names and even the most savvy user will have trouble detecting anything is amiss.

Thus, while you are going here and there in your browser tabs mess, one of the site change itself (including the tab icon…) pretending to be another site, and asking for your login and password. It’s not strange that a site will ask your login and password more than once, thus you will think this is a legit request and you will be ****ed.

To see this attack in action open a new tab and visit the link where they describe this new kind of phishing; then move to another tab. You will see the tab you left changing itself to mimic GMail.

I tried this on my PC and it worked with Firefox but not with Chrome, but it worked on the Opera browser installed on my Touc Pro2, as you can see in the images below (only the tab icon didn’t change).

Before the attack

Moving to another tab and going back shows the site changed (the icon didn’t, though)  

Scaring, especially when it says:

Every time you include a third-party script on your page, or a Flash widget, you leave yourself wide open for an evil doer to use your website as a staging ground for this kind of attack.

So, time to be more careful with those tabs…

Link: Azarask

Via:  Ilium Software Twitter

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