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CloudFlare's Heartbleed challenge cracked

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Re: CloudFlare's Heartbleed challenge cracked

#21

Love to see a post on how it was done and the tools he used.

Same here. I was trying other ways in instead of Heartbleed, and made no progress. On the positive side, I wasn't expecting Cloudflare to be vulnerable to a timing attack anyway.

EDIT He won't reveal it for a week. Good on him. https://twitter.com/indutny/status/454790640078176256

Re: CloudFlare's Heartbleed challenge cracked

#22
post #19

Earlier quoted context omitted.

Putting that mapping in /etc/hosts lets your machine skip DNS lookup for that hostname, and just use his IP for that domain name. Then, your browser checks the received certificate against the authenticated TLS connection, and sees that all is well, allowing you to connect without a warning. Since the browser does not warn of a certificate mismatch, he must have a valid certificate for 'cloudflarechallenge.com'. QED.

But seems like only the http connection is working, i get a warning in Chrome when visiting https://cloudflarechallenge.com . Isn't that the only situation where the key would be checked. That's the part that doesn't make sense.

Try https://www.cloudflarechallenge.com/

Re: CloudFlare's Heartbleed challenge cracked

#23
post #19

Earlier quoted context omitted.

Putting that mapping in /etc/hosts lets your machine skip DNS lookup for that hostname, and just use his IP for that domain name. Then, your browser checks the received certificate against the authenticated TLS connection, and sees that all is well, allowing you to connect without a warning. Since the browser does not warn of a certificate mismatch, he must have a valid certificate for 'cloudflarechallenge.com'. QED.

But seems like only the http connection is working, i get a warning in Chrome when visiting https://cloudflarechallenge.com . Isn't that the only situation where the key would be checked. That's the part that doesn't make sense.

Subdomains are separate domains, and you put www.cloudflarechallenge.com in your hosts, so when going to the domain without the www subdomain your entry in the hosts is not used.

Either go to https://www.cloudflarechallenge.com or remove the www subdomain from your hosts entry.

Re: CloudFlare's Heartbleed challenge cracked

#24
post #19

Earlier quoted context omitted.

Putting that mapping in /etc/hosts lets your machine skip DNS lookup for that hostname, and just use his IP for that domain name. Then, your browser checks the received certificate against the authenticated TLS connection, and sees that all is well, allowing you to connect without a warning. Since the browser does not warn of a certificate mismatch, he must have a valid certificate for 'cloudflarechallenge.com'. QED.

But seems like only the http connection is working, i get a warning in Chrome when visiting https://cloudflarechallenge.com . Isn't that the only situation where the key would be checked. That's the part that doesn't make sense.

Try setting 'www.cloudflarechallenge.com' in /etc/hosts instead, and when visiting the URL hit - to ensure your browser isn't caching anything.

I see Indutny's blog for 'https://www.cloudflarechallenge.com'[/etc/hosts mapped to 165.225.128.15] in both FF and Chrome.

Re: CloudFlare's Heartbleed challenge cracked

#25
post #11

We have reached out via twitter to this invidiual as to coordinate the delivery of the $10,000 bounty we offered. If anyone is already in contact with them please direct them to https://news.ycombinator.com/item?id=7572530

Somehow I totally missed your bounty offer. Not that I was going to win if I had seen it, but where was it mentioned?

Re: CloudFlare's Heartbleed challenge cracked

#26
post #11

We have reached out via twitter to this invidiual as to coordinate the delivery of the $10,000 bounty we offered. If anyone is already in contact with them please direct them to https://news.ycombinator.com/item?id=7572530

Somehow I totally missed your bounty offer. Not that I was going to win if I had seen it, but where was it mentioned?

(at least) in a comment near the top in the hn annoncement thread for the challenge

Re: CloudFlare's Heartbleed challenge cracked

#27
post #3

https://twitter.com/indutny/status/454767565991325697 How do you not love this guy.

> How do you not love this guy.

Me? Insane jealousy.

(Although I do like that he made me google up the X-Men And Teen Titans cover art to confirm the source of his Twitter pic.)

Re: CloudFlare's Heartbleed challenge cracked

#29
post #10
post #6

Earlier quoted context omitted.

On the other hand, if anyone asks me to justify all that "unproductive time" this week, I don't need to handwave and explanations any more.

I was lucky, my boss understood pretty quickly how big a deal it was. My project manager didn't, though, but he did pretty quick when I cracked our dev server and told him his password for a couple of services. It was fun playing pen tester and getting paid for it this week :)

Do you guys store passwords in plain text? Shouldn't you only be able to get password hashes from a vulnerable server? I might be reading too much into your statement, but I'd like to know if I'm misunderstanding the situation.

Re: CloudFlare's Heartbleed challenge cracked

#30
The important thing to know here is that you not only have to change your current certs you ALSO HAVE TO REVOKE THE OLD ONE.

If you only change your current cert to get a new key but you don't go through the revocation process of the old certificate if someone managed to get the old one they can still use it for a MiTM attack - as both certs would be valid to any client.

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