VeriSign tips to protect from a man-in-the-middle attack

(18/03/2009)

In light of a new man-in-the-middle (MITM) type of attack, VeriSign Inc. is providing simple tips end users and businesses can use to effectively thwart the online threat.

The MITM attack relies on a user being fooled into going to the wrong Web site. Common techniques for fooling visitors include phishing e-mails, false wireless hotspots, and most recently poisoning of insecure DNS servers. The scheme uses a fraudulent server to intercept communications between a user’s browser and a legitimate Web site, and then acts as a proxy, collecting sensitive information over HTTP (not HTTPS) between the browser and the fraudulent server.

What makes this attack different than previous MITM attacks is that the fraudulent site attempts to leverage false visual cues, namely replacing the fraudulent site’s favicon with a padlock icon, which has traditionally been recognised as a visual cue to signify an SSL-protected site. But while this scheme is capable of reproducing the padlock, it is not capable of recreating the legitimate HTTPS indicator or the even more noticeable green glow in the address bar of high security Web browsers, where the site is secured with an Extended Validation SSL Certificate.

To help protect from a MITM attack, VeriSign offers the following tips to end users and businesses.

End users:
* Look for the “green glow”: Man-in-the-middle and phishing attacks in the wild today can be combated through Extended Validation (EV) SSL Certificates and to notice when there is an absence of green. EV SSL Certificates definitively confirm the identity of the organisation that owns the Web site. Online criminals do not have access to EV SSL Certificates for the sites they're counterfeiting and therefore cannot spoof the green glow that shows that an authenticated Web site is secure.
* Download the latest version of high security Web browsers such as Internet Explorer 7 or higher, FireFox 3 or higher, Google Chrome, Safari or Opera.
* Take advantage of authentication credentials such as tokens and other forms of two factor authentication for sensitive accounts.
* Treat e-mails from unknown senders with a high degree of skepticism, and don’t click links to access secure sites (type in the Web address into the browser).

Businesses:
* Adopt EV SSL and educate customers on what the green or glow means. Put the EV SSL Certificate on your home page and every other page where a secure transaction takes place.
* Don’t offer logins on pages that are not already in an SSL session.
* Offer two factor authentication to customers as an optional way to add another layer of security when accessing accounts.
* Don’t include links in e-mails to customers, and encourage them to download the latest version of their favourite browsers.

“Though online criminals have been using low-authentication SSL Certificates in phishing and man-in-the-middle types of attacks for years, the Black Hat presentation last week is a good reminder for end users to remain vigilant when transacting online,” said Tim Callan, vice president of product marketing for VeriSign. “Security threats come in many forms and staying a step ahead requires education on the end-user side and a comprehensive, layered security approach from Web sites to help ensure that users have a secure experience.”

Related topics:  Hacking and intrusion prevention   Internet and Web security 

Print version | Email to a friend | Related articles

Data breaches: Trends, costs and best practices gives you all the latest information on securing personal and corporate data, key recommendations for immediate action to improve data security, and how to respond to data breaches.

Other Security news and resources