RFCs about S/MIME | RFC Editor

S/MIME (Secure/Multipurpose Internet Mail Extensions) secure email
S/MIME version 3.1 introduced a mechanism to provide end-to-end cryptographic protection of email message headers. However, few implementations generate messages using this mechanism, and several legacy implementations have revealed rendering or security issues when handling such a message.
This document updates the S/MIME specification (RFC 8551) to offer a different mechanism that provides the same cryptographic protections but with fewer downsides when handled by legacy clients. Furthermore, it offers more explicit usability, privacy, and security guidance for clients when generating or handling email messages with cryptographic protection of message headers.
The Header Protection scheme defined here is also applicable to messages with PGP/MIME (Pretty Good Privacy with MIME) cryptographic protections.
S/MIME version 3.1 introduced a mechanism to provide end-to-end cryptographic protection of email message headers. However, few implementations generate messages using this mechanism, and several legacy implementations have revealed rendering or security issues when handling such a message.
This document updates the S/MIME specification (RFC 8551) to offer a different mechanism that provides the same cryptographic protections but with fewer downsides when handled by legacy clients. Furthermore, it offers more explicit usability, privacy, and security guidance for clients when generating or handling email messages with cryptographic protection of message headers.
The Header Protection scheme defined here is also applicable to messages with PGP/MIME (Pretty Good Privacy with MIME) cryptographic protections.
The S/MIME development community benefits from sharing samples of signed or encrypted data. This document facilitates such collaboration by defining a small set of X.509v3 certificates and keys for use when generating such samples.
The S/MIME development community benefits from sharing samples of signed or encrypted data. This document facilitates such collaboration by defining a small set of X.509v3 certificates and keys for use when generating such samples.
This document specifies an extension to "The JSON Meta Application Protocol (JMAP) for Mail" (RFC 8621) for returning the S/MIME signature verification status.
This document specifies an extension to "The JSON Meta Application Protocol (JMAP) for Mail" (RFC 8621) for returning the S/MIME signature verification status.
This document specifies identifiers and challenges required to enable the Automated Certificate Management Environment (ACME) to issue certificates for use by email users that want to use S/MIME.
This document specifies identifiers and challenges required to enable the Automated Certificate Management Environment (ACME) to issue certificates for use by email users that want to use S/MIME.
This document specifies conventions for X.509 certificate usage by Secure/Multipurpose Internet Mail Extensions (S/MIME) v4.0 agents. S/MIME provides a method to send and receive secure MIME messages, and certificates are an integral part of S/MIME agent processing. S/MIME agents validate certificates as described in RFC 5280 ("Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile"). S/MIME agents must meet the certificate-processing requirements in this document as well as those in RFC 5280. This document obsoletes RFC 5750.
This document specifies conventions for X.509 certificate usage by Secure/Multipurpose Internet Mail Extensions (S/MIME) v4.0 agents. S/MIME provides a method to send and receive secure MIME messages, and certificates are an integral part of S/MIME agent processing. S/MIME agents validate certificates as described in RFC 5280 ("Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile"). S/MIME agents must meet the certificate-processing requirements in this document as well as those in RFC 5280. This document obsoletes RFC 5750.
This document defines Secure/Multipurpose Internet Mail Extensions (S/MIME) version 4.0. S/MIME provides a consistent way to send and receive secure MIME data. Digital signatures provide authentication, message integrity, and non-repudiation with proof of origin. Encryption provides data confidentiality. Compression can be used to reduce data size. This document obsoletes RFC 5751.
This document defines Secure/Multipurpose Internet Mail Extensions (S/MIME) version 4.0. S/MIME provides a consistent way to send and receive secure MIME data. Digital signatures provide authentication, message integrity, and non-repudiation with proof of origin. Encryption provides data confidentiality. Compression can be used to reduce data size. This document obsoletes RFC 5751.
Mobile messaging applications used with the Session Initiation Protocol (SIP) commonly use some combination of the SIP MESSAGE method and the Message Session Relay Protocol (MSRP). While these provide mechanisms for hop-by-hop security, neither natively provides end-to-end protection. This document offers guidance on how to provide end-to-end authentication, integrity protection, and confidentiality using the Secure/Multipurpose Internet Mail Extensions (S/MIME). It updates and provides clarifications for RFCs 3261, 3428, and 4975.
Mobile messaging applications used with the Session Initiation Protocol (SIP) commonly use some combination of the SIP MESSAGE method and the Message Session Relay Protocol (MSRP). While these provide mechanisms for hop-by-hop security, neither natively provides end-to-end protection. This document offers guidance on how to provide end-to-end authentication, integrity protection, and confidentiality using the Secure/Multipurpose Internet Mail Extensions (S/MIME). It updates and provides clarifications for RFCs 3261, 3428, and 4975.
This document describes how to use secure DNS to associate an S/MIME user's certificate with the intended domain name, simi