Do you realize that these application are asking users for their password in this moment? That seems to me even worse than oauth with these "caviots"
On Tue, Oct 22, 2013 at 7:54 PM, Chris Steipp csteipp@wikimedia.org wrote:
On Tue, Oct 22, 2013 at 10:33 AM, Petr Bena benapetr@gmail.com wrote:
I am basically interested only in oauth that can be used by remote applications / processes running on user's PC, which isn't available yet
This is the second most requested feature that we don't support yet.
We've been looking at options for it. All solutions would basically require we make a second class of OAuth Consumers. This has precedence: OAuth 2 makes the distinction between "confidential" and "public" consumers, and Twitter's xAuth has to be specifically enabled on your OAuth Consumer. We're debating making a similar distinction for our OAuth Consumers, but we don't want to get into the situation where we need to give lots of caviots to our users that, "Yes, this OAuth thing is secure, as long as Consumers of this type are doing these things, but these other ones also need to do these other things...".
On Tue, Oct 22, 2013 at 7:18 PM, Chris Steipp csteipp@wikimedia.org wrote:
On Tue, Oct 22, 2013 at 1:57 AM, Merlijn van Deen <valhallasw@arctus.nl wrote:
Hi Chris,
On 22 October 2013 05:45, Chris Steipp csteipp@wikimedia.org wrote:
OAuth does not support this, since the results of an api call using OAuth signatures aren't signed (only the request from the OAuth consumer is signed), so it's possible that an attacker could forge a response back to the application, and the application would think a different user was logged in. This is less likely if you're using
https
for
your api calls, but it's surprisingly hard to get https right [1],
even
if
you trust all your CA's.
(...)
This is a common issue is being addressed by the OpenID Connect
extension
to OAuth2, which allows the application to request information about
the
person doing the authorization, and the result is signed by the
server to
prevent tampering.
(...)
I'm a bit confused by this -- I was under the impression https would be enough to confirm I'm actually talking to the WMF's servers. The main argument in [1] against just using https seems to be it's easy to ignore invalid certificates. Is there another reason why it's dangerous to
assume
you're talking to mw.o if the certificates check out?
That's correct. The issue is more that we (the security community) keep finding code out there that doesn't correctly handle the verification ( http://www.cs.utexas.edu/~shmat/shmat_ccs12.pdf was one of the popular surveys of the subject). It's often the underlying libraries at fault (errors parsing the certificates, or the revocation lists, that fail
open),
or common programming mistakes (like how mediawiki set CURLOPT_SSL_VERIFYHOST to true, instead of 2, for a very long time). But if you accept that your current libraries are probably flawed, and so you keep your libraries up to date, and you're careful about how you're doing the verification at the application layer, you *should* be fine.
Basically, I'm not quite sure whether using OIDC will help alleviate
this
problem - you get a response back, but you still have to check the signature! And with the ease of not checking the signature, you're basically back to the same problem with not checking the ssl
certificate.
Correct. Hopefully, applications that really need to know the identity
of a
user (like UTRS) will go through the bother of checking the signature (in both OpenID Connect, and the intermediate solution I'm proposing, this is an HMAC signature using a pre-established secret, so it should be easy enough that the effort is worth the security).
Nonetheless, I think it's useful to add an authentication mechanism that follows a standard - which is clearly not the case with the current 'api.php?meta=userinfo' calls.
Merlijn
[1]
http://blog.astrumfutura.com/2010/10/do-cryptographic-signatures-beat-ssltls...
Wikitech-l mailing list Wikitech-l@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikitech-l
Wikitech-l mailing list Wikitech-l@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikitech-l
Wikitech-l mailing list Wikitech-l@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikitech-l
Wikitech-l mailing list Wikitech-l@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikitech-l