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Re: [tor-talk] Using passwords with TOR

> And a follow-up question if I may - how do you verify that the ssl
> connection is to the site you want & not something else?   eg:
> http://www.wired.com/threatlevel/2010/03/packet-forensics/
> What's the defense against that type of attack?

Well if CA's are giving intermediate CA's to adversaries, and those
adversaries are issuing certs MITM on the fly in hardware... then
yeah, you've got major problems.

Same for if the apps are bundling random CA's as trusted.

And for CA's issuing certs (same subject, different hash) on demand.

The traditional answer to all such things is still:
- Verify and enforce the cert fingerprint, ignore the CA stuff.
- Verify and enforce the DNS.
- Hope your adversaries don't pass on the above attacks and then
simply obtain the real cert and redirect your IP traffic to themselves.

But you watch your hop count, latency and server particulars right?
Then your adversary mimics those, so...

The only defense you have left is context, particularly human
factors. Whether in real time (a recognized voice, video, data
challenge, etc), and perhaps aided by crypto chained back to a
former, known good, session (ZRTP, etc). You're not supposed to
pass sensitive data unless you know who's on the other end of the
channel first.

Even via Tor, people who don't have anything to worry about, generally
don't have anything to worry about, unless their padlock icon is
broken. If your money, etc, is siphoned, with a good icon (via the
above weaknesses), and you can't get it back with an affadavit,
choose another financial provider.
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