Extended Validation Certificate

In 2005 Melih Abdulhayoglu, CEO of the Comodo Group , convened the first meeting of the organization that became the CA/Browser Forum, hoping to improve standards for issuing SSL/TLS certificates.[3] On June 12, 2007, the CA/Browser Forum officially ratified the first version of the Extended Validation (EV) SSL Guidelines, which took effect immediately. The formal approval successfully brought to a close more than two years of effort and provided the infrastructure for trusted website identity on the Internet. Then, in April 2008, the forum announced version 1.1 of the guidelines, building on the practical experience of its member CAs and relying-party application software suppliers gained in the months since the first version was approved for use.

Most major browsers created special user interface indicators for pages loaded via HTTPS secured by an EV certificate soon after the creation of the standard. This includes Microsoft Edge 12, Google Chrome 1.0, Internet Explorer 7.0, Firefox 3, Safari 3.2, Opera 9.5.[4] Furthermore, some mobile browsers, including Safari for iOS, Windows Phone, Firefox for Android, Chrome for Android, and iOS, added such UI indicators. Usually, browsers with EV support display the validated identity—usually a combination of organization name and jurisdiction—contained in the EV certificate's 'subject' field.

In most implementations, the enhanced display includes:

• The name of the company or entity that owns the certificate;
• A lock symbol, also in the address bar, that varies in color depending on the security status of the website.

By clicking on the lock symbol, the user can obtain more information about the certificate, including the name of the certificate authority that issued the EV certificate.

In August 2019, Google Chrome 76 and Firefox 70 browsers announced plans to redesign user interfaces to remove emphasis for EV certificates.[5] Firefox 70 removed the distinction in the omnibox or URL bar (EV and DV certificates are displayed similarly with just a lock icon), but the details about certificate EV status are accessible in the more detailed view that opens after click on the lock icon.[6]

The legal entity names are not unique, therefore an attacker who wants to impersonate an entity might incorporate a different business with the same name (but, e.g., in a different state or country) and obtain a valid certificate for it, but then use the certificate to impersonate the original site. In one demonstration, a researcher incorporated a business called "Stripe, Inc." in Kentucky and showed that browsers display it similarly to how they display certificate of payment processor "Stripe, Inc." incorporated in Delaware. Researcher claimed the demonstration setup took about an hour of his time, US$100 in legal costs and US$77 for the certificate. Also, he noted that "with enough mouse clicks, [user] may be able to [view] the city and state [where entity is incorporated], but neither of these are helpful to a typical user, and they will likely just blindly trust the [EV certificate] indicator".[17]

Since EV certificates are being promoted and reported[18] as a mark of a trustworthy website, some small business owners have voiced concerns[19] that EV certificates give undue advantage to large businesses. The published drafts of the EV Guidelines[20] excluded unincorporated business entities, and early media reports[19] focused on that issue. Version 1.0 of the EV Guidelines was revised to embrace unincorporated associations as long as they were registered with a recognized agency, greatly expanding the number of organizations that qualified for an Extended Validation Certificate. A list of EV certificates with price and features comparison is available for small business to select a cost-effective certificate.

In 2006, researchers at Stanford University and Microsoft Research conducted a usability study[21] of the EV display in Internet Explorer 7. Their paper concluded that "participants who received no training in browser security features did not notice the extended validation indicator and did not outperform the control group", whereas "participants who were asked to read the Internet Explorer help file were more likely to classify both real and fake sites as legitimate".

While proponents of EV certificates claim they help against phishing attacks,[22] security expert Peter Gutmann states the new class of certificates restore a CA's profits which were eroded due to the race to the bottom that occurred among issuers in the industry. Gutmann calls this phenomenon "PKI-Me-Harder".

The introduction … of so-called high-assurance or extended validation (EV) certificates that allow CAs to charge more for them than standard ones, is simply a case of rounding up twice the usual number of suspects—presumably somebody’s going to be impressed by it, but the effect on phishing is minimal since it is not fixing any problem that the phishers are exploiting. Indeed, cynics would say that this was exactly the problem that certificates and CAs were supposed to solve in the first place, and that “high-assurance” certificates are just a way of charging a second time for an existing service. A few years ago certificates still cost several hundred dollars, but now that the shifting baseline of certificate prices and quality has moved to the point where they can be obtained for $9.95 (or even for nothing at all) the big commercial CAs have had to reinvent themselves by defining a new standard and convincing the market to go back to the prices paid in the good old days.

This deja-vu-all-over-again approach can be seen by examining Verisign’s certificate practice statement (CPS), the document that governs its certificate issuance. The security requirements in the EV-certificate 2008 CPS are (except for minor differences in the legalese used to express them) practically identical to the requirements for Class 3 certificates listed in Verisign’s version 1.0 CPS from 1996. EV certificates simply roll back the clock to the approach that had already failed the first time it was tried in 1996, resetting the shifting baseline and charging 1996 prices as a side-effect. There have even been proposals for a kind of sliding-window approach to certificate value in which, as the inevitable race to the bottom cheapens the effective value of established classes of certificates, they’re regarded as less and less effective by the software that uses them…[23]