Hello TAG!

I'm requesting a TAG review of Secur<em>er</em> Contexts.

Secure Context's threat model encompasses the transport layer. This proposal would extend it to include attackers with the ability to inject code into a victim's document (by tricking either the server or client-side code), and attackers who seek to include a victim's resources into a context where they may be vulnerable to side-channel attacks. This extension of the threat model would allow us to likewise extend the [SecureContext] IDL attribute to express new requirements for new mitigations.

• Explainer: https://github.com/mikewest/securer-contexts/
• Security and Privacy self-review: This is not a new feature in the typical sense, but a discussion of the ways in which I'd like us to collectively be able to restrict new (and existing!) features. I think it would feed into the self-review process, as opposed to being directly subject to it (but I'm happy to fill out the questionnaire if y'all disagree about its relevance).
• Primary contacts (and their relationship to the specification):
  • Mike West (@mikewest, Google)
• Organization/project driving the design: Moi.
• External status/issue trackers for this feature (publicly visible, e.g. Chrome Status): None yet. This seems solidly architectural in nature, so I came to y'all first. I intend to send it to WebAppSec (and Twitter, I suppose) directly after filing this bug.

Further details:

• I am passingly familiar with the TAG's API Design Principles, and in particular its discussion of Secure Contexts in Section 2.10.
• The group where the work on this design is being done (or is intended to be done in the future): WICG -> WebAppSec + IDL
• Existing major pieces of multi-stakeholder review or discussion of this design: None.
• Major unresolved issues with or opposition to this design: None.
• This work is being funded by: Google, via my paychecks.

You should also know that the TAG was the venue in which Secure Contexts began (hello, @diracdeltas!).

We'd prefer the TAG provide feedback as (please delete all but the desired option) review feedback as a comment in this issue, @-notifying @mikewest.

:heart: