- From: Erik Nygren <erik+ietf@nygren.org>
- Date: Mon, 11 Mar 2019 22:52:55 -0400
- To: "ietf-http-wg@w3.org Group" <ietf-http-wg@w3.org>
- Cc: Rich Salz <rsalz@akamai.com>, Brian Sniffen <bsniffen@akamai.com>, "Bishop, Mike" <mbishop@akamai.com>, Erik Nygren - Work <nygren@akamai.com>
- Message-ID: <CAKC-DJh4oT3qE98BWj393A8LYcL6U2hxuChvVC6L4=RZHqJgFw@mail.gmail.com>
This draft on "Best practices for TLS Downgrade" is intended as a starting point for discussion on a topic that many people would like to ignore but which introduces risk into the ecosystem. We'd like to bring some co-authors onboard (especially from other CDNs and browsers/OSes) and incorporate lessons learned elsewhere as well. While "don't downgrade!" is almost always the "correct" solution, it isn't always viable. Getting alignment on best practices may at least help provide better visibility into the associated risks, such as by exposing to clients when an insecure downgrade to cleartext is happening and by stripping request data most likely leak private information. Feedback and suggestions for additions are most welcome, and we're also interested in discussing more in Prague. Erik ---------- Forwarded message --------- From: <internet-drafts@ietf.org> Date: Mon, Mar 11, 2019 at 4:08 PM Subject: I-D Action: draft-richsalz-httpbis-https-downgrade-00.txt To: <i-d-announce@ietf.org> A New Internet-Draft is available from the on-line Internet-Drafts directories. Title : Best practices for TLS Downgrade Authors : Brian Sniffen Mike Bishop Erik Nygren Rich Salz Filename : draft-richsalz-httpbis-https-downgrade-00.txt Pages : 8 Date : 2019-03-11 Abstract: Content providers delivering content via CDNs will sometimes deliver content over HTTPS (or both HTTPS and HTTP) but configure the CDN to pull from the origin over cleartext and unauthenticated HTTP. From the perspective of a client, it appears that their requests and associated responses are delivered over HTTPS, while in reality their requests are being sent across the network in-the-clear and responses are delivered unauthenticated. This exposes user request data to pervasive monitoring [RFC7258]; it also means response data may be tampered with by active adversaries. Terminating TLS connections on a load balancer and contacting a backend over cleartext has long been common within data centers, but doing this TLS termination and downgrade to HTTP at a CDN introduces additional risk when the unprotected traffic is sent over the general Internet, sometimes across national boundaries. While it would be nice to say "never do this," customer demand, content provider use-cases, and market forces today make it impossible for CDNs to not support downgrade. However, following a set of best practices can provide visibility into when this is happening and can reduce some of the risks. The IETF datatracker status page for this draft is: https://datatracker.ietf.org/doc/draft-richsalz-httpbis-https-downgrade/ There are also htmlized versions available at: https://tools.ietf.org/html/draft-richsalz-httpbis-https-downgrade-00 https://datatracker.ietf.org/doc/html/draft-richsalz-httpbis-https-downgrade-00 Please note that it may take a couple of minutes from the time of submission until the htmlized version and diff are available at tools.ietf.org. Internet-Drafts are also available by anonymous FTP at: ftp://ftp.ietf.org/internet-drafts/ _______________________________________________ I-D-Announce mailing list I-D-Announce@ietf.org https://www.ietf.org/mailman/listinfo/i-d-announce Internet-Draft directories: http://www.ietf.org/shadow.html or ftp://ftp.ietf.org/ietf/1shadow-sites.txt
Received on Tuesday, 12 March 2019 09:26:20 UTC