Re: [COSE] Security consideration -- signing recommened in addition to encryption
Hannes Tschofenig <hannes.tschofenig@gmx.net> Sat, 04 March 2023 16:57 UTC
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Date: Sat, 04 Mar 2023 17:57:10 +0100
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To: Laurence Lundblade <lgl@island-resort.com>, cose <cose@ietf.org>
References: <FBE8F6FB-5951-4864-8F69-359067A0ED56@island-resort.com>
From: Hannes Tschofenig <hannes.tschofenig@gmx.net>
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Subject: Re: [COSE] Security consideration -- signing recommened in addition to encryption
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Hi Laurence, thanks for the feedback. Could you say a bit more about the use case you have in mind where authenticity is not required? Ciao Hannes Am 03.03.2023 um 21:22 schrieb Laurence Lundblade: > The COSE HPKE draft has this security consideration: > > The COSE_Encrypt structure MUST be authenticated using COSE > constructs like COSE_Sign, COSE_Sign1, COSE_MAC, or COSE_MAC0. > > It is really good this text is there, but I’d like to tweak it a bit: > > * Change MUST to SHOULD because there are (theoretically) cases > where authenticity is not needed. Perhaps some comment that most > use cases will need authenticity to defend against forgery attacks > — the attacker is likely to have access to the recipients public > key. (Also prefer to avoid 2119 terms belong in security > considerations). > * Say that the AEAD in HPKE base_mode is not a substitute for the > authenticity provided by COSE_Sign and such. > > > LL > > > _______________________________________________ > COSE mailing list > COSE@ietf.org > https://www.ietf.org/mailman/listinfo/cose
- [COSE] Security consideration -- signing recommen… Laurence Lundblade
- Re: [COSE] Security consideration -- signing reco… Hannes Tschofenig
- Re: [COSE] Security consideration -- signing reco… Laurence Lundblade