On Thu, Apr 01, 2021 at 01:32:08PM -0700, Martin Duke via Datatracker wrote: > Martin Duke has entered the following ballot position for > draft-ietf-oauth-access-token-jwt-12: No Objection > > When responding, please keep the subject line intact and reply to all > email addresses included in the To and CC lines. (Feel free to cut this > introductory paragraph, however.) > > > Please refer to https://www.ietf.org/iesg/statement/discuss-criteria.html > for more information about IESG DISCUSS and COMMENT positions. > > > The document, along with other ballot positions, can be found here: > https://datatracker.ietf.org/doc/draft-ietf-oauth-access-token-jwt/ > > > > ---------------------------------------------------------------------- > COMMENT: > ---------------------------------------------------------------------- > > (2.1) "...can use any signing algorithm." I presume there ought to be some > qualifiers on allowed algorithms? > > (4) and (5) "This specification > does not provide a mechanism for identifying a specific key as the > one used to sign JWT access tokens." > > I don't understand; there's a key ID right there in the token header?
The concern here is about identifying keys authorized to sign JWS access tokens. The server-provided metadata that lists such keys has a single bucket that covers keys used for signing different things, so you don't get any security benefit from key isolation, and a compromise of any of the (other) keys listed by the server would allow the attacker to sign JWT access tokens that are accepted as valid. So in a sense this is not about which key was actually used, but rather which key is supposed to be used. > (4) I presume it's important that any resouree server rejection of the token > should be constant-time. Is this somewhere in the RFC tree, or do we need to > explicitly say it here and/or in Security Considerations? (A good question, but I don't actually have the answer handy in memory.) -Ben _______________________________________________ OAuth mailing list OAuth@ietf.org https://www.ietf.org/mailman/listinfo/oauth
