RFC 8446, "The Transport Layer Security (TLS) Protocol Version 1.3", August 2018

Errata ID: 6143
Status: Reported
Type: Technical
Publication Format(s) : TEXT
Reported By: Ben Smyth
Date Reported: 2020-04-29

Section 4.2.7 says:

As of TLS 1.3, servers are permitted to send the "supported_groups"
extension to the client.

Notes:

It is unclear whether servers are permitted to send the "supported_groups" extension to
the client without solicitation, i.e., when the client does not first send the extension to the
server. Clarification would be useful.

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