[Gen-art] draft-ietf-ipsecme-ikev2-downgrade-prevention-05 ietf last call Genart review

[Linda Dunbar via Datatracker <[e-mail]>]

Document: draft-ietf-ipsecme-ikev2-downgrade-prevention
Title: Downgrade Prevention for the Internet Key Exchange Protocol Version 2
(IKEv2) Reviewer: Linda Dunbar Review result: Ready with Nits

I am the assigned Gen-ART reviewer for this draft. The General Area
Review Team (Gen-ART) reviews all IETF documents being processed
by the IESG for the IETF Chair.  Please treat these comments just
like any other last call comments.

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Document: draft-ietf-ipsecme-ikev2-downgrade-prevention-??
Reviewer: Linda Dunbar
Review Date: 2026-06-12
IETF LC End Date: 2026-06-12
IESG Telechat date: Not scheduled for a telechat

Summary: This draft updates IKEv2 by adding a negotiation signal and modified
AUTH transcript so both peers authenticate the same full IKE_SA_INIT
conversation, preventing attackers from silently downgrading the connection to
weaker key exchange methods or stripped extensions

Major issues: None

Minor issues: None

Nits/editorial comments:

- Section 6 says the responder includes the notification “regardless of whether
it was received in the request or not,” and later says the modified
authentication calculation is used only if a peer both sent and received the
notification. Just wondering what to do when only one direction contains the
notification.

- Section 4: s/Having these preconditions the goal of the attacker is to
eavesdrop/Given these preconditions, the goal of the attacker is to eavesdrop/

- should expand PQ/T on the first use.

Best regards,
Linda Dunbar