Public Key Pinning Extension for HTTP

Document Type Replaced Internet-Draft (individual)
Authors Chris Evans  , Chris Palmer 
Last updated 2011-12-05 (latest revision 2011-11-14)
Replaces draft-evans-palmer-hsts-pinning
Replaced by RFC 7469
Stream (None)
Intended RFC status (None)
Expired & archived
pdf htmlized (tools) htmlized bibtex
Stream Stream state (No stream defined)
Consensus Boilerplate Unknown
RFC Editor Note (None)
IESG IESG state Replaced by draft-ietf-websec-key-pinning
Telechat date
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This Internet-Draft is no longer active. A copy of the expired Internet-Draft can be found at


This memo describes an extension to the HTTP protocol allowing web host operators to instruct user agents (UAs) to remember ("pin") the hosts' cryptographic identities for a given period of time. During that time, UAs will require that the host present a certificate chain including at least one Subject Public Key Info structure whose fingerprint matches one or more of the pinned fingerprints for that host. By effectively reducing the scope of authorities who can authenticate the domain during the lifetime of the pin, pinning may reduce the incidence of man-in-the-middle attacks due to compromised Certification Authorities and other authentication errors and attacks.


Chris Evans (
Chris Palmer (

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