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Black Hat Presentation Highlights SSL Encryption Flaws
nk497 writes "Hackers at the Black Hat conference have shown that SSL encryption isn't as secure as online businesses would like us to think. Independent hacker Moxie Marlinspike showed off several techniques to fool the tech behind the little padlock on your screen. He claimed that by using a real world attack on several secure websites such as PayPal, Gmail, Ticketmaster and Facebook, he garnered 117 email accounts, 16 credit card numbers, seven PayPal logins and 300 other miscellaneous secure logins."
Come on, this does not highlight vulnerabilities of SSL, but errors in implementing it for specific platforms. This was always a weak point.
If you don't implement the security, you're not secure. The author claims that some browsers don't check to see that an intermediate certificate is actually authorized to sign other certificates. So naturally there's a simple attack based on that, but it doesn't really show a flaw in SSL.
The author also complains about companies which post secure forms on non-secure pages, which is a valid complaint but is also a case of "You're using it wrong" rather than a problem with the protocols. Most users are never going to check for the lock (or whatever), so the basic problem will be with us forever, but banks don't have to screw it up by putting login forms on non-secure pages normally. Yes, it's convenient to have a login on a home page, and yes it would consume too many resources to make every home page hit into an https hit, but security ought to count for something, particularly with a bank.
It looks like there are a couple of things, but their main one is a man-in-the-middle attack based on the user not paying attention to the browser's SSL flags. See the difference between page 61 and 62 of their presentation: https://www.blackhat.com/presentations/bh-dc-09/Marlinspike/BlackHat-DC-09-Marlinspike-Defeating-SSL.pdf
They show on page 69 how it looks once they substitute a lock image for the favicon (if they had wanted to be Extra Evil, they'd have given their fake favicon a blue background, which would have made firefox 3 look exactly like it was SSL protected, except for the S missing in the URL)
They then proceed to show how allowing unicode in the hostname continues to confuse and confound people. Register a cert for *.foo.com, then set up a hostname of www.google.com[unicodeslashlike]login[unicodeslashlike]blah[unicodeslashlike]blah[unicodeslashlike]blah.foo.com and presto, you have a valid certificate for a site that looks more or less like https://www.google.com/login/blah/blah/blah.foo.com, except that it's not hosted by google.
Basically all of these are attacks on the end user, what you do or don't do on the server won't change a thing.
If I have been able to see further than others, it is because I bought a pair of binoculars.
End-to-end encryption is required at all levels of the internet. Until that is available, the internet will never be secure, because someone will be able to read the non-encrypted data you send and reply with a fake response.