- From: Peter Eckersley <pde@eff.org>
- Date: Tue, 12 Jul 2016 16:43:53 -0700
- To: Brad Hill <hillbrad@gmail.com>
- Cc: Chris Palmer <palmer@google.com>, Tanvi Vyas <tanvi@mozilla.com>, "public-webappsec@w3.org" <public-webappsec@w3.org>, Mike West <mkwst@google.com>, Richard Barnes <rbarnes@mozilla.com>, Christoph Kerschbaumer <ckerschbaumer@mozilla.com>, "dveditz@mozilla.com" <dveditz@mozilla.com>
On Tue, Jul 12, 2016 at 08:42:42PM +0000, Brad Hill wrote: > I understand the value; I guess I would leave it up to UA implementers. We > currently have implementations in Chrome, Firefox and Safari. Would those > implementers be interested in adding a mode with fallback? On what > timeline? Should we try to do this before moving Upgrade Insecure Requests > to Proposed Recommendation? I'm curious to hear Tanvi and Mike's thoughts on this (not sure who worked on the Safari implementation), but just personally I think it would be a mistake to proceed further with a version of the UIR spec that's a double-edged sword for site operators. I think we need to have a version of it that strictly helps to mitigate mixed content situations without making some of them worse. Mike, if it were helpful, I'd be happy to draft a spec PR for this. > > On Wed, Jul 6, 2016 at 7:15 PM Peter Eckersley <pde@eff.org> wrote: > > > On Fri, Jul 01, 2016 at 07:41:14PM +0000, Brad Hill wrote: > > > I agree it creates no new vulnerabilities, but I question the benefits. > > > > > > Yes, user agents do and will continue to block insecure scripts. This is > > > exactly the crux. If you got a new cert for your http site that depends > > on > > > external scripts to render important user experiences, make buttons > > click, > > > or just measure the ads that pay to keep you in business, you can't start > > > sending users to the https version yet if those scripts don't upgrade. > > > This is why I think that it's not realistic to think that Certbot could > > > just start flipping the switch automatically. Modern web apps depend > > > deeply on scripts and things will break. > > > > There are few possible switches here: (1) enable existing UIR, (2) enable > > an > > HTTP -> HTTPS redirect (3) enable UIR-FB-passive-mixed-content-only (4) > > enable > > UIR-FB-all-mixed-content (5) enable CSP reporting to > > https://report-uri.io or some similar service. > > > > Currently we offer switches (1) and (2). We'd like to flip (1) by default, > > but cannot because it breaks HTTP images on some HTTPS pages that would > > otherwise work fine (but trigger Chrome's triangle warning). If (3) > > existed, > > we could and would flip it safely as the default for Certbot users who ask > > for > > security settings automation. > > > > We still couldn't and wouldn't flip (2) by default. And we wouldn't flip > > (4) > > by default, but it would be nice to be able to offer it as a prominent > > feature, especially in the form of a single switch that combines (2) (4) > > and > > (5) together (conditional on the client UA being new enough to support > > (4)). > > > > > > > > > > > > Certainly there is some population of sites that could benefit from > > > UIR-FB. If the cost to implement is very cheap, let's do it. If it's > > not, > > > we should try to understand a bit how big that population is. > > > > > > On Fri, Jul 1, 2016 at 11:59 AM Chris Palmer <palmer@google.com> wrote: > > > > > > > I'm less concerned about non-secure script in an otherwise-secure page, > > > > because good UAs block it outright anyway. Point your favorite browser > > at > > > > https://mixed-script.badssl.com/, for example. Desktop Firefox and > > Chrome > > > > refuse to load the non-secure script, but have an option to let the > > person > > > > load it anyway (with suitably frightening messaging); Safari and > > Chrome for > > > > iOS, and it seems Safari for desktop, don't even have that option. IE > > makes > > > > it a bit too easy to load the non-secure script for my tastes, but > > even so > > > > it's safe by default. And most browsers do still distinguish > > fully-secure > > > > page-loads from those that have some mixed display content. > > > > > > > > So, assuming a good UA, UIR-FB seems to be much more of a win for HTTPS > > > > deployment than a safety risk. > > > > > > > > My boundless optimism ;) allows me to hope that the slowness of the 2 > > > > round-trips (as Tanvi mentioned) would be incentive enough for > > > > some/many/most site operators to use UIR-FB only as a temporary aid > > and not > > > > a permanent mode of deployment. Surely, some will leave it permanent, > > so > > > > we'd still have to do all the usual outreach and evangelism. > > > > > > > > I don't relish latency, evangelism, or complexity, but I don't see that > > > > UIR-FB creates a new vulnerability, and the benefits could be > > substantial. > > > > > > > > -- > > Peter Eckersley pde@eff.org > > Chief Computer Scientist Tel +1 415 436 9333 x131 > > Electronic Frontier Foundation Fax +1 415 436 9993 > > -- Peter Eckersley pde@eff.org Chief Computer Scientist Tel +1 415 436 9333 x131 Electronic Frontier Foundation Fax +1 415 436 9993
Received on Tuesday, 12 July 2016 23:44:19 UTC