Fraudulent *.google.com certificate issued

Posted Aug 30, 2011 19:12 UTC (Tue) by dkg (subscriber, #55359)
In reply to: Fraudulent *.google.com certificate issued by butlerm
Parent article: Fraudulent *.google.com certificate issued

intercepting, re-encrypting, and forwarding a large fraction of Google's HTTPS traffic would be a bit of a trick too.

Unless, of course, the adversary is doing a more targeted attack against a specific network they happen to be upstream of.

In that case, they can ignore all the rest of the traffic, and focus their resources on compromising traffic coming out of a network segment they are interested in.

But my larger concern here isn't about Google being compromised. That's bad, but (as the current situation shows) Google actually has the resources and infrastructure to potentially catch when something is going wrong. What about smaller sites? Google vs. a medium-sized government is like King Kong vs. Godzilla. It's not clear who would win. But what if one of these titans turns their focus on small fry? Our current infrastructure suggests a sorry future for the hope of a free and autonomous global network.

Fraudulent *.google.com certificate issued

Posted Aug 30, 2011 19:38 UTC (Tue) by raven667 (subscriber, #5198) [Link] (3 responses)

How does that work in practice? Wouldn't you need to have a key signed by the next highest upstream authority to make this work, or do clients not do any checking if the key for com. changes between requests? Wouldn't the only sure-fire way to do spoofing for foobix.com. be to have a shadow root with its own complete key infrastructure for all possible zones all the way down to the one that is being spoofed? You aren't going to be able to re-use any of the legitimate public key material because the trust relationships won't be compatible with the spoofed resources, right?

As long as clients don't accept the upstream keys in the hierarchy changing between requests, to spoof one child domain you have to spoof them all, right?

Fraudulent *.google.com certificate issued

Posted Aug 30, 2011 22:53 UTC (Tue) by jebba (guest, #4439) [Link] (2 responses)

I'm not certain of it, but it appears to me that x86_64 Firefox in Fedora 14/15 doesn't check the intermediate certs:
https://bugzilla.redhat.com/show_bug.cgi?id=732144

Fraudulent *.google.com certificate issued

Posted Aug 31, 2011 0:29 UTC (Wed) by cesarb (subscriber, #6266) [Link] (1 responses)

Did you check if Firefox had cached the intermediate certificates? It can make things appear to work, but when you try with another computer which has not visited yet any site which uses the same intermediate certificate, it will fail.

(I believe Firefox switched to also caching intermediate certificates because, since Internet Explorer caches intermediate certificates, a lot of people forgot to put the whole chain on their servers, and it "worked" on IE but failed - as it should - on Firefox.)

Fraudulent *.google.com certificate issued

Posted Aug 31, 2011 1:35 UTC (Wed) by jebba (guest, #4439) [Link]

Good suggestion. I believed I would have blown out my ~/.mozilla in the various tests, but I'll confirm that.