Hardening DNSSEC against collision weaknesses in SHA-1 and other cryptographic hash algorithms

Document Type Expired Internet-Draft (individual)
Author Tony Finch 
Last updated 2020-09-10 (latest revision 2020-03-09)
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This Internet-Draft is no longer active. A copy of the expired Internet-Draft can be found at


DNSSEC deployments have often used the SHA-1 cryptographic hash algorithm to provide authentication of DNS data. This document explains why SHA-1 is no longer secure for this purpose, and deprecates its use in DNSSEC signatures. This document updates RFC 8624.


Tony Finch (dot@dotat.at)

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)