RFC 9495 · PROPOSED STANDARD · 2023

Certification Authority Authorization Processing for Email Addresses

Overview

RFC 9495, “Certification Authority Authorization Processing for Email Addresses”, is a Proposed Standard document published in October 2023 by C. Bonnell. The canonical text is published by the RFC Editor.

Abstract

The Certification Authority Authorization (CAA) DNS resource record (RR) provides a mechanism for domains to express the allowed set of Certification Authorities that are authorized to issue certificates for the domain. RFC 8659 contains the core CAA specification, where Property Tags that restrict the issuance of certificates that certify domain names are defined. This specification defines a Property Tag that grants authorization to Certification Authorities to issue certificates that contain the id-kp-emailProtection key purpose in the extendedKeyUsage extension and at least one rfc822Name value or otherName value of type id-on-SmtpUTF8Mailbox that includes the domain name in the subjectAltName extension.

Abstract as published in the RFC, via rfc-editor.org.

What “Proposed Standard” means

An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.

Read this RFC

The canonical text of RFC 9495 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

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