Hi Ben,

I appreciate the clarity on the decision, but I do believe that the
rationale and justification of it are inconsistent - internally to the
message itself, with the public discussion, and with Mozilla's stated
values, goals, and past public statements. I hope to highlight these, in
the event that these were oversights in the evaluation process and worthy
of reconsideration.

# Inconsistent internally

Within the message, you note that the primary purpose is
> We use an open, public, and transparent procedure, and we evaluate the
risks to users’ security and privacy

and later state:
> While the risks presented by a root and an intermediate may be very
similar, they are not identical. For example, a root certificate can issue
other CA certificates, which introduces the risk that a CA certificate will
be mis-issued. While the intermediate CA certificates proposed here cannot
be used to issue CA certificates, and can only be used to issue DV server
certificates.

Unfortunately, this suggestion of "less risk" is both technically flawed,
and inconsistent with the explanation of the rationale. To focus
exclusively on the latter, the message later states:
> Because GoDaddy is putting its own root at risk, such reviews have gone
beyond the minimum requirements of Mozilla and the CA/Browser Forum's
Baseline Requirements

This suggests that the conclusion is based on the assumption that, should
Certainly have issues, GoDaddy would be appropriate to distrust. As
discussed in previous messages, this clearly demonstrates the significantly
greater risk posed by the existence of an intermediate, and shows that the
ability to issue sub-CAs is entirely orthogonal to the risk remediation
process, namely, sanction against GoDaddy. GoDaddy represents one of the
largest CAs in Mozilla's program, and it seems unlikely that Mozilla is
willing to take action except in the most egregious of scenarios, due to
the end-user impact. If this is the statement, then it seems Certainly
poses high risk to users, because it can "take out" GoDaddy. Alternatively,
if this is not the statement, then it shows the inconsistency in the
conclusion in that GoDaddy is under very little functional risk, and thus
has less incentive to perform adequate review - as highlighted by Andrew
Ayer's review, my review, and Certainly's own disclosed incidents thus far.

Notably, while Certainly has noted it's using Boulder, it's worth
highlighting that both Certainly and GoDaddy failed to discover issues with
that implementation until reported by another CA [1]. This should raise
questions about the degree of thoroughness and correctness of the review
performed - of code, practice, and policy - and highlight the questionable
nature of relying on GoDaddy's assertions.

# Inconsistent with the public discussion

Without repeating your excellent summary of the discussion thus far, it
shows that there is limited support in the community for continuing
forward. While understandably, the role of Mozilla is to weigh many
different viewpoints, and not just count by number and volume (length), it
should raise some degree of concern that the emphasis of risk that exists
here seems unaddressed. Much of this seems to be dismissed under the basis
that GoDaddy has performed an analysis sufficient for Mozilla to ignore its
own extant policies and procedures for managing CA risk, which also seems
inconsistent with the degree of public discussion and transparency.

For example, although GoDaddy has shared their process, there's been no
substantive response to the concerns raised by Andrew Ayer that discusses
procedurally how this was overlooked. Although we have the response from
Wayne Thayer regarding the intent, it highlights the possibility that both
GoDaddy and Certainly are operating on certain undocumented assumptions
about the interpretation of language and/or requirements that would
normally be part of a public discussion during review. This, equally,
should raise questions about the degree of thoroughness and correctness of
the review performed.

# Inconsistent with Mozilla's stated values, goals, and past statements

The nature of risk presented here certainly raises questions with respect
to Principles 4 and 8 [2]. I think it's questionable to suggest that
GoDaddy's internal review satisfies those. From examining the spreadsheet
[3], it's also clear that GoDaddy's primary review was conducted not with
the same Mozilla principles in mind, but rather, whether there was
consistency and/or conflict with GoDaddy's (Starfield's) CP/CPS. This an
important step for cross-signing, but it does not address the same goals,
nor ensure the same perspectives. The additional documents [4] supplied are
very clearly forms of self-review, and lack both transparency and
accountability that demonstrate a commitment to these principles.

With respect to past statements, it's difficult to reconcile the glowing
remarks about the value of audits, and the diligence provided by
third-parties (e.g. GoDaddy), with Mozilla's statement of concerns with
respect to proposals such as the eIDAS Regulation [5], or its justification
for its root store [6]. For instance, in the concerns regarding the EU
Trust List, it's highlighted that there are concerns with transparency,
audits, and risk management. There is no transparency into the ongoing
GoDaddy supervision, only in the conclusion, which denies users appropriate
transparency into the discussions and interpretations, as highlighted
above. While Mozilla highlighted concerns with the irregularity of the
audits in [5], past concerns raised by Mozilla [7] have highlighted there
is far more to supervising CAs and minimizing risk than audits alone.
However, your statement in favor of positive dispensation for Certainly
seems to rest largely, if not entirely, on an assumption that audits are
alone sufficient. And in terms of risk management, this thread has shown a
number of ways in which Mozilla is failing to fully consider its risk
management. These risk management concerns are echoed in [6] about the
value of the root store, but this reply seems to separate out the selection
of roots from those of intermediates, as if intermediates aren't an
intrinsic part of both the value of, and risk to, Mozilla's policies and
practices highlighted in that post.

Equally, when one considers the super-CA policy, [8], it suggests that if
one wants to start a super-CA, the process is rather to add the super-CA as
a root first, before signing subordinates, such that newly-added
subordinates can use the expedited process and bypass the review currently
required if there is an existing parent/subordinate relationship.

# Conclusion

Ultimately, Mozilla's decisions for its programs are Mozilla's, and there
is no question that there is incredible value in the transparency of this
discussion, and value in the opportunity to participate in it. However, the
conclusion seems to argue that audits and basicConstraints are sufficient
to mitigate risk to end users, such that it's not necessary for Mozilla to
perform a careful, detailed, and diligent review. It also seems to discount
the numerous concerns raised by participants about the process.

I appreciate the discussion with respect to the wiki, but note that it's
been even longer that concerns have been raised around such cross-signing
events (e.g. [9], [10]), to which Mozilla did not substantively respond.
Originally proposed as part of Policy 2.8, it now seems to have been
adopted in full independent of that, and it leaves it ambiguous whether
current proposals [11] are advocating for a Mozilla-led review, or whether
they're instead weakening the intent of both policy and language to being
led by CAs.

My biggest concern, however, remains that it's difficult to see the
distinction Mozilla is making here, with respect to delegating and
deferring to GoDaddy, and how that squares with concerns it has raised
delegating and deferring to other organizations, whether super-CA operators
([8]) or the European Trust Lists ([5], [7]). Mozilla is, functionally,
outsourcing the oversight and compliance, and it's unclear the value that
Mozilla, or users, derive from this process, other than expediting the
inclusion of CAs. Can Mozilla articulate why it cannot substitute "EU
Supervisory Bodies" in for "GoDaddy" in the rationale to continue, and thus
automatically adopt the European Trust Lists, provided it also has the
ability to remove? It's difficult to see, based on the stated rationale,
why it could not, and that's concerning.

As I said, I have no objections if the view is that such subordinate CAs
should be moved to the front of the queue for prioritization, provided that
the same processes occur and without any predisposition towards including
the CA. The rigorous vetting [12] that Mozilla has endorsed [13] does not
appear to be performed here, or appears to be performative rather than
substantive, and that remains a concern.


[1] https://bugzilla.mozilla.org/show_bug.cgi?id=1752452
[2] https://www.mozilla.org/en-US/about/manifesto/
[3] https://bugzilla.mozilla.org/attachment.cgi?id=9266000
[4] https://bugzilla.mozilla.org/attachment.cgi?id=9266001
[5]
https://blog.mozilla.org/netpolicy/files/2020/09/Mozilla-Attachment-to-the-European-Commission-Review-of-eIDAS.pdf
[6]
https://blog.mozilla.org/security/2019/02/14/why-does-mozilla-maintain-our-own-root-certificate-store/
[7] https://www.ccadb.org/documents/TSP_Technical_Best_Practices_eIDAS.pdf
[8] https://wiki.mozilla.org/CA/Subordinate_CA_Checklist#Super-CAs
[9]
https://groups.google.com/a/mozilla.org/g/dev-security-policy/c/AA5G1bzOwZQ/m/-L7Q_bdABQAJ
[10]
https://groups.google.com/a/mozilla.org/g/dev-security-policy/c/AA5G1bzOwZQ/m/mS5rard2BQAJ
[11]
https://groups.google.com/a/mozilla.org/g/dev-security-policy/c/r9ZeggoH9KA/m/NZwE3TuYAwAJ
[12] https://www.eff.org/document/eidas-letter-2022
[13]
https://blog.mozilla.org/en/security/mozilla-eff-cybersecurity-experts-publish-letter-on-dangers-of-article-452-eidas-regulation/

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