CAA

Cybersecurity / 24 Sep 2026 / 6 min read

CAA Records Constrain Public Certificate Issuance

A public certificate authority does more than validate control of a DNS name. Before issuing a certificate, a CA that follows the CAA specification also checks DNS for a Certification Authority Authorization policy relevant to each requested name. That policy can narrow the set of issuers permitted to create certificates for the domain. CAA is an issuance control, not a replacement for domain-control validation. An authorized CA still has to apply its normal validation and issuance requirements. The record adds another decision: even after validation succeeds, is this issuer permitted by the domain’s published CAA policy?

Cybersecurity CAA

Cybersecurity / 24 Sep 2026 / 4 min read

CAA Narrows Certificate Issuance to Authorized CAs

Public certificate authorities validate control of a domain name before issuing a certificate, but domain control is not the only policy a domain operator can publish. Certificate Authority Authorization (CAA), specified in RFC 8659, adds a DNS-based signal that states which CAs are permitted to issue for a name. CAA does not replace domain-control validation. It adds another decision point before issuance: a conforming CA checks the applicable CAA policy and proceeds only when that policy permits the CA to issue the requested certificate.

Cybersecurity CAA

Cybersecurity / 23 Sep 2026 / 4 min read

CAA Records Restrict Certificate Authority Issuance

CAA Records Restrict Certificate Authority Issuance A public certificate authority can issue a certificate only after satisfying its validation and policy requirements. DNS Certification Authority Authorization adds another control: the domain holder can publish a CAA resource record set that states which issuers are authorized for a name. CAA is an issuance constraint, not a replacement for domain-control validation. An authorized CA still has to perform the validation required by its certificate policy. Conversely, successful domain validation does not permit a compliant CA to disregard an applicable CAA restriction.

Cybersecurity PKI

Cybersecurity / 22 Sep 2026 / 6 min read

CAA Records Constrain Certificate Authority Issuance

CAA Records Constrain Certificate Authority Issuance A certificate authority can validate control of a domain and still face a separate policy question: is this CA authorized by the domain operator to issue for that name? Certification Authority Authorization, or CAA, gives the DNS namespace a record type for expressing that constraint. CAA operates before certificate issuance. A participating public CA checks the relevant DNS CAA policy and evaluates whether its issuer identity is authorized. The mechanism does not make a certificate trusted, revoke an existing certificate, or tell a browser to reject a certificate after issuance. It narrows the set of issuers that should create new certificates for the domain.

Cybersecurity DNS

Cybersecurity / 21 Sep 2026 / 5 min read

DNS CAA Narrows Which CAs May Issue Certificates

DNS CAA Narrows Which CAs May Issue Certificates A publicly trusted certificate authority can issue a certificate only after completing the validation required by its policy and the applicable ecosystem rules. DNS Certification Authority Authorization (CAA) adds another control: a domain can publish which CAs are authorized to issue certificates for that DNS namespace. CAA does not replace domain-control validation, certificate transparency, or certificate verification by clients. It constrains issuance at the CA side. A CA processing a request checks the relevant CAA policy before issuance and must not issue when the policy forbids it.

Cybersecurity PKI

Cybersecurity / 15 Sep 2026 / 7 min read

CAA Records Constrain Public Certificate Issuance at the DNS Boundary

CAA Records Constrain Public Certificate Issuance at the DNS Boundary A public certificate can pass every browser check after issuance even if the domain operator never intended to use the certificate authority that created it. The Web PKI has several controls for detecting or responding to bad issuance, but DNS Certification Authority Authorization (CAA) acts earlier: it gives a domain holder a way to state which issuers are permitted to create certificates for a name.

Cybersecurity DNS

Cybersecurity / 14 Sep 2026 / 7 min read

CAA Records Narrow Certificate Issuance Authority

CAA Records Narrow Certificate Issuance Authority A public certificate authority can validate control of a domain correctly and still be the wrong authority for that domain’s operating policy. DNS Certification Authority Authorization, or CAA, addresses that gap by giving a domain operator a published way to constrain which certificate authorities are permitted to issue certificates for its names. Domain-control validation establishes that an applicant can satisfy a validation method. CAA expresses a separate authorization decision: among the public certificate authorities capable of performing validation, which ones may proceed with issuance for this domain?

Cybersecurity TLS