DV Certificate details:
Certificate Domain Validation checking warning
Comodo Dragon uses advanced domain validation technology originally developed in Comodo Verification Engine. It performs additional analysis of a domain's SSL certificate to warn about those that been issued with Domain Only Validation.
History behind Certificate validations:
An important motivation for using digital certificates with SSL was to add trust to online transactions by requiring website operators to undergo vetting with a certificate authority (CA) in order to get an SSL certificate. However, commercial pressures have led some CAs to introduce "domain validation only" SSL certificates for which minimal verification is performed of the details in the certificate.
Most browsers' user interfaces did not clearly differentiate between low-validation certificates and those that have undergone more rigorous vetting. Since any successful SSL connection causes the padlock icon to appear, users are not likely to be aware of whether the website owner has been validated or not. As a result, fraudsters (including phishing websites) have started to use SSL to add perceived credibility to their websites.
By establishing stricter issuing criteria and requiring consistent application of those criteria by all participating CAs, EV SSL certificates are intended to restore confidence among users that a website operator is a legally established business or organization with a verifiable identity.