RFC 9155 · PROPOSED STANDARD · 2021

Deprecating MD5 and SHA-1 Signature Hashes in TLS 1.2 and DTLS 1.2

Overview

RFC 9155, “Deprecating MD5 and SHA-1 Signature Hashes in TLS 1.2 and DTLS 1.2”, is a Proposed Standard document published in December 2021 by L. Velvindron, K. Moriarty, A. Ghedini. It updates RFC 5246. The canonical text is published by the RFC Editor.

Abstract

The MD5 and SHA-1 hashing algorithms are increasingly vulnerable to attack, and this document deprecates their use in TLS 1.2 and DTLS 1.2 digital signatures. However, this document does not deprecate SHA-1 with Hashed Message Authentication Code (HMAC), as used in record protection. This document updates RFC 5246.

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 9155 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

Relationships to other RFCs
This RFC updates
RFC 5246
Other RFCs from 2021

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