[TLS] [Technical Errata Reported] RFC8446 (8908)

RFC Errata System <rfc-editor@rfc-editor.org> Thu, 07 May 2026 19:00 UTC

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Date: Thu, 07 May 2026 12:00:15 -0700
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CC: albin.johansson@vector.com, tls@ietf.org, rfc-editor@rfc-editor.org
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Subject: [TLS] [Technical Errata Reported] RFC8446 (8908)
Archived-At: <https://mailarchive.ietf.org/arch/msg/tls/Nplw03abrNLh6qpI0UXUF4I9jJs>

The following errata report has been submitted for RFC8446,
"The Transport Layer Security (TLS) Protocol Version 1.3".

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You may review the report below and at:
https://www.rfc-editor.org/errata/eid8908

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Type: Technical
Reported by: Albin Johansson <albin.johansson@vector.com>

Section: 4.2.7

Original Text
-------------
struct {
    NamedGroup named_group_list<2..2^16-1>;
} NamedGroupList;

Corrected Text
--------------
struct {
    NamedGroup named_group_list<2..2^16-2>;
} NamedGroupList;

Notes
-----
The specified maximum legal length of the named_group_list vector in the NamedGroupList structure is 2^16-1 bytes. This is invalid because NamedGroup is an enum that occupies two bytes, but 2^16-1 is not an exact multiple of the element size (2 bytes), as required in Section 3.4. It appears that the intended upper bound should be 2^16-2 bytes instead.

AD note: This is scheduled for the bis document via https://github.com/tlswg/tls13-spec/pull/1380 

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--------------------------------------
RFC8446 (draft-ietf-tls-tls13-28)
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Title               : The Transport Layer Security (TLS) Protocol Version 1.3
Publication Date    : August 2018
Author(s)           : E. Rescorla
Category            : PROPOSED STANDARD
Source              : Transport Layer Security
Stream              : IETF

[TLS] [Technical Errata Reported] RFC8446 (8908) RFC Errata System