[keycloak-dev] Avoid older user agents?

[Stian Thorgersen]

----- Original Message -----
> From: "Bill Burke" <bburke at redhat.com>
> To: "Stian Thorgersen" <stian at redhat.com>
> Cc: "Gabriel Cardoso" <gcardoso at redhat.com>, keycloak-dev at lists.jboss.org
> Sent: Wednesday, 7 August, 2013 12:39:52 PM
> Subject: Re: [keycloak-dev] Avoid older user agents?
> 
> 
> 
> On 8/7/2013 4:45 AM, Stian Thorgersen wrote:
> >
> >
> > ----- Original Message -----
> >> From: "Bill Burke" <bburke at redhat.com>
> >> To: "Gabriel Cardoso" <gcardoso at redhat.com>
> >> Cc: keycloak-dev at lists.jboss.org
> >> Sent: Tuesday, 6 August, 2013 5:04:39 PM
> >> Subject: Re: [keycloak-dev] Avoid older user agents?
> >>
> >> For SSO login, we should support as old as possible (no javascript,
> >> backward compatible to HTML 4? 3? 2? I don't know you tell me....).
> >
> > HTML4 transitional is fine, pretty much covers 99.9999% of browsers in use
> > today. We can use JavaScript as long as it's progressive enhancements (for
> > example autofocus or placeholder replacement). The biggest issue is around
> > css/style and testing that it's "pixel perfect", there's several websites
> > out there that can help with this. There may be an official list of
> > browsers Redhat supports, but I would think recent versions of Chrome,
> > Firefox, Safari, Opera (these are all generally updated and there's very
> > few old versions around). For IE6 is announced dead by MS themselves, and
> > IE7 has a relatively low usage, so I would think IE8 is sufficient. That's
> > not to say it won't work with older browsers, it may just look a bit crap.
> >
> >>
> >> For admin UI, we can be more restrictive, IMO.  The admin UI, is not
> >> just a UI though.  It is a set of REST services that can be called from
> >> javascript (or whatever langage/platform you want).  For security
> >> reasons we might want to restrict the types of browsers that can make
> >> these REST requests.
> >
> > I'm wondering if limiting on agent header is false security as it can be
> > easily changed.
> >
> 
> I was thinking more of XSS.  If somebody has logged into Keycloak with
> an old browser.  We're protecting the user, not preventing a direct
> attack.  Am I right here?

XSS is what I'm thinking about, as the malicious code could just set the user-agent header on any XHR requests to mimic a new "safe" browser. BTW I'm not expert and I'm just speculating ;)

> 
> > Checking user agent before setting HttpOnly is also IMO not necessary as
> > most browsers do (in fact IE does all the way back to 6 and Firefox to
> > 3!). Anyone that still uses a browser that doesn't support it today are
> > using a heavily out of date (and unsupported browser) so it will be
> > riddled with vulnerabilities in any case.
> >
> 
> No, we would always set HttpOnly.  The cookie spec allows for arbitrary
> values.

Sorry, I worded that incorrectly. I meant that we could just create the cookie in any case (always with HttpOnly) as it seems to me that >99% browsers are covered. 

A browser that is very vulnerable to XSS attacks might not even need a cookie to get the required info?

> 
> I just think its so important to think of any security vulnerability and
> close it up.  If we get one security hack, our credibility takes a huge hit.

IMO if someone uses an old browser with known vulnerabilities it's the browser that was hacked, not Keycloak. I guess this is the meat of what I'm trying to say.

What about a warning message on the login screen if someone uses an old unsupported browser?

> 
> 
> --
> Bill Burke
> JBoss, a division of Red Hat
> http://bill.burkecentral.com
>