It might be helpful if the authors could describe how they have addressed the 
feedback received?

From my point of view, there are still many problems with this document. 
AFAICT, almost none of the points I’ve raised previously have been addressed. 
Although the document no longer deprecates encryption algorithms, it still 
contains problematic statements about them, and clauses like this one in 
section 3.1:

"Each of these multiple algorithms must be independently fully specified. The 
operations performed by each of them MUST NOT vary when used alongside other 
algorithms. So for instance, for JOSE, alg values and enc values MUST each be 
fully specified, and their behaviors MUST NOT depend upon one another."

These requirements would make ECDH-ES with direct key agreement unusable, 
because it includes the “enc” value in the KDF context info, so very directly 
depends on the specific content encryption algorithm. (And this kind of context 
inclusion absolutely *should* be done for security). IMO most of section 3 is 
wrong or misleading and should be removed entirely. 

Section 5 should say how implementations that want to support old and new 
algorithms for a transition period should handle this: publish the same key 
twice with different “alg” values, remove the “alg” field entirely (not a good 
idea), etc.

Section 6.1 on RSA states:

"This is not a problem in practice, because RSA libraries accommodate keys of 
different sizes without having to use different code. Therefore, for example, 
there are not known cases in the wild where it would be useful to have 
different algorithm identifiers for RSASSA-PKCS1-v1_5 with SHA-256 and 2048-bit 
keys versus 4096-bit keys or 8192-bit keys. Therefore, the RSA signature 
algorithms are not replaced by this specification.”

But, as I’ve pointed out multiple times now, this is not the case. Many 
FIPS-compliant HSMs limit RSA key sizes, e.g.: 

https://thalesdocs.com/gphsm/ptk/5.9/docs/Content/PTK-C_Admin/Sec_Policies_User_Roles/Typ_Sec_Policies/FIPS.htm
 
<https://thalesdocs.com/gphsm/ptk/5.9/docs/Content/PTK-C_Admin/Sec_Policies_User_Roles/Typ_Sec_Policies/FIPS.htm>
"RSA: must be 2048, 3072, or 4096 bits”

I’m not pointing this out because I think we need to specify RSA key sizes in 
algorithm identifiers, but to again point out that the definition of 
“fully-specified” that this draft proposed is arbitrary and inconsistent. As 
I’ve said many times before, I would have far less concern about a document 
that simply registers Ed25519/Ed448 and marks EdDSA as discouraged.

The first paragraph of the security considerations section 7 is outright wrong 
and should be removed. There is no additional attack surface before these 
changes. If anything, this spec introduces more attack surface!

Appendix A is entirely opinion and should be removed - there is no consensus 
about which combinations of ECDH-ES algorithms should be considered and this 
document shouldn’t make any statement about it.

— Neil

> On 21 Aug 2024, at 15:10, Karen ODonoghue <[email protected]> wrote:
> 
> JOSE working group members,
> 
> This email initiates a second working group last call for the Fully
> Specified Algorithms document:
> https://datatracker.ietf.org/doc/draft-ietf-jose-fully-specified-algorithms/
> 
> The authors have updated the draft based on WGLC comments and
> discussions at IETF 120, and the chairs have polled the working group
> about the readiness for WGLC. Seeing no opposition, we've decided to
> proceed with a second WGLC.
> 
> Please review the document in detail and reply to this message
> (keeping the subject line intact) with your opinion on the readiness
> of this document for publication and any additional comments that you
> have.
> 
> This will be a three week WGLC. Please submit your responses by 13
> September 2024.
> 
> Thank you,
> Karen (for the JOSE WG chairs)
> 
> _______________________________________________
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