RFC 7633 · PROPOSED STANDARD · 2015

X.509v3 Transport Layer Security Feature Extension

Overview

RFC 7633, “X.509v3 Transport Layer Security Feature Extension”, is a Proposed Standard document published in October 2015 by P. Hallam-Baker. The canonical text is published by the RFC Editor.

Abstract

The purpose of the TLS feature extension is to prevent downgrade attacks that are not otherwise prevented by the TLS protocol. In particular, the TLS feature extension may be used to mandate support for revocation checking features in the TLS protocol such as Online Certificate Status Protocol (OCSP) stapling. Informing clients that an OCSP status response will always be stapled permits an immediate failure in the case that the response is not stapled. This in turn prevents a denial-of-service attack that might otherwise be possible.

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 7633 is hosted at rfc-editor.org. Available in TXT,HTML.

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