Overview#
Domain Validated Certificate the lowest and most common
Certificate Level Of Assurance issued from a
Certificate Authority checks the
Control of the applicant to use a specific
DNS Domain.
No company identity information is vetted and no information is displayed other than encryption information within the Secure Site Seal.
Domain Validated Certificate is simply for confidentiality, (e.g. encryption)
Domain Validated Certificate#
Domain Validated Certificate is the lowest
Certificate Level Of Assurance and usually consists only of "
Domain Control Validation"
Registration Authority (or
Certificate Authority)
MUST only issue a
certificate after performing Domain Control Validation (DCV). One way of validating domain ownership is through
HTTP validation, done by uploading a text file to a specific
HTTP endpoint on the
Website they want to secure. Another DCV method is done using
email verification, where an email with a validation code link is sent to the administrative contact for the
DNS Domain.
HTTP Validation #
Suppose Alice buys the
DNS Domain name aliceswonderland.com and wants to get a dedicated
certificate for this domain.
Alice chooses to use
Lets encrypt as their
Certificate Authority. First, Alice must generate their own
Private Key and create a
Certificate Signing Request (
CSR). She sends the
CSR to Let’s Encrypt, but the
Certificate Authority won’t issue a certificate for that
CSR and
Private Key until they know
Alice owns aliceswonderland.com.
Alice can then choose to prove that she owns this domain through
HTTP validation.
When Let’s Encrypt performs DCV over HTTP, they require Alice to place a randomly named file in the /.Well-known/acme-challenge path for her website. The CA must retrieve the text file by sending an HTTP GET request to http://aliceswonderland.com/.well-known/acme-challenge/<random_filename>. An expected value must be present on this endpoint for DCV to succeed.
For HTTP validation, Alice would upload a file to http://aliceswonderland.com/.well-known/acme-challenge/YnV0dHNz
where the body contains:
curl http://aliceswonderland.com/.well-known/acme-challenge/YnV0dHNz
GET /.well-known/acme-challenge/YnV0dHNz
Host: aliceswonderland.com
HTTP/1.1 200 OK
Content-Type: application/octet-stream
YnV0dHNz.TEST_CLIENT_KEY
The CA instructs them to use the
Base64 token YnV0dHNz. TEST_CLIENT_KEY in an account-linked key that only the certificate requestor and the CA know. The CA uses this field combination to verify that the certificate requestor actually owns the domain. Afterwards, Alice can get her certificate for her website!
More Information#
There might be more information for this subject on one of the following: