Research has shown that most people are unable to tell whether they are at an authentic website that is using SSL encryption (see The Emperor’s New Security Indicators). This is part of the reason people are so susceptible to phishing. Web browsers provide enough information to tell if SSL is on, but it is presented in a poor manner (as a small lock icon). Other bad security practices, like the website embedding its own lock icon and saying “secure login”, make matters even worse.

The problem is that people tend to notice glaring differences, but do not take explicit steps to check for security. They shouldn’t have to. Firefox 3 tries to improve SSL indicators for “Extended Verification” certificates by displaying the company name in green to the left of the URL along with the fav-icon. It looks like this:

Unfortunately, this indicator is still just text, plus an insecure/unsigned fav-icon. One must deliberately read it to verify the site’s identity, so it is likely to go unnoticed if the user is at a different site, just like like previous security indicators. If a hacker can compromise any site that has an EV certificate using cross-site scripting (a common problem on many sites), then he can create a believable phishing page. Sure, the company name will be different, but the fav-icon could presumably be spoofed and the address bar will still have the green indicator.

 Firefox 3 SSL indicators for EV certificates are a much better than previous indicators, but there is still room for improvement. The problem is that there isn’t a striking visual difference between the security indicators for different sites with EV certificates. Confusion is possible, especially if one can spoof the fav-icon. What I propose is that each site with an EV certificate also sign a logo for display in place of the hostname. The logo should also be a registered trademark, which, by law, must be clearly different from other trademarks. In fact, the test for trademark violation is “confusion,” so using registered trademarks for EV certificates guarantees (legally) that there will be no visual confusion. Here is an example of what, in my mind, SSL indicators should look like:

This way, any deviation from PayPal.com would immediately stand out to the user and serve as a much better indicator not only of SSL, but also the identity of the current site.

This article covers a topic that is somewhat unrelated to computer security. However, Internet advertising does share some similarities with one security issue: phishing. Both cost-per-click (CPC) ads and phishing attacks use social engineering to elicit participation from the user. The main difference between phishing and advertising is that the former aims to deceive and defraud the user, while the latter tries to sell an actual product. This article discusses an approach for effective ad placement on social networks (Facebook, in particular). Some of the same principles could also be applied to deliver better context-aware phishing attacks or spam, which are described in a recent paper from our research group available here.

(more…)