Extended Validation (EV) SSL certificates have been touted by Certificate Authorities and browser vendors as a solution to the poor validation standards for issuing traditional SSL certificates. It was previously thought that EV certificates are not affected by attacks that allow malicious hackers to obtain a non-EV SSL certificate, such as the MD5 collision attack or the widely publicized failures of some CAs to validate domain ownership before issuing certificates.
Unfortunately, it turns out that the security offered by EV certificates is not any better than the security of even the cheapest $12 SSL certificate. In this talk we will show how any attacker who can obtain a non-EV SSL certificate for a website can perform completely transparent man-in-the-middle attacks on any SSL connection to that site, even if the website is protected is by an EV certificate and the users are diligently inspecting all information contained in the SSL certificates.
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