Nowadays everyone will be familiar with phishing attacks. It is basically the process of obtaining confidential information from a person by communicating with the victim (using emails, phone calls etc.) posing as someone else. The typical phishing attack includes creating a fake login page, storing them in a server and emailing the victim with the fake login page link. Now a new research paper from InfoSec student, Henning Klevjer shows how a hacker can create phishing attacks without the need for storing the fake login page on a server.
This method uses URI or universal resource identifier which is basically a string of characters that are used to identify a name or a resource. Using URI, the required data (the code for login page in this case) is stored within the URI with the following scheme
Here <data> will contain the fake login page. The procedure for creating a phishing URI starts with creating a login page using the code from the original page. The original code is modified accordingly so that the entered data such as password are sent to a location as desired by the hacker. This page is then encoded using a scheme called Base64. Base64 is a method of encoding binary data to ASCII format which will increase the data size by around 33%. The next and the final step is to append this information to the URI.
The final URI will be extremely long and suspicious looking one. But as all browsers support legacy URI schemes, it will be rendered properly, as long as it doesn’t extend more than the maximum URL limit allowed by the browser.
Although, the large URI can be masked using a URL shortening service, Henning states that this method has some major limitations thanks to implementation of data URIs in Chrome and Internet Explorer.
You can read more about this method here(PDF).
Via: Naked Security