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DigiCert Revocation Incident (CNAME Domain Validation)
will be revoking certificates that did not have proper Domain Control Verification (DCV). Before issuing a certificate to a customer, DigiCert validates the customer’s control or ownership over the domain name for which they are requesting a certificate using one of several methods approved by the CA/Browser Forum (CABF).
Failing to include the underscore is considered a security risk because there is potential for a collision between an actual domain and the subdomain used for verification. As a result, domain validations that used this method where customers did not add the underscore prefix were non-compliant. We apologize if this causes a business disruption to you and are standing by to assist you with validating your domain and issuing replacement certificates immediately.
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