Iran forged the wrong SSL certificate • Hacker News Board

Re: Iran forged the wrong SSL certificate

#11

Post by InclinedPlane » Thu, Sep 01, 2011, 8:44 AM UTC

fletchowns wrote: post #5

How come it's just one CA that is needed to ensure the trust of a domain, especially one as important as *.google.com? It seems like it's only a matter of time before something like this happens again.

The idea is that all CA's are effectively fully trustworthy. The public keys for the CA's certs are loaded into browsers. When a specific SSL cert is created the private key is generated by the buyer (and never revealed) then the public key for that is sent to the CA and signed. In this way a link of trust is created between the CA and whoever bought the SSL cert.

Now, when a browser is used to go to a website using SSL it will ask that site for its cert, which contains the public key and the digital signature from the CA. If the cert is signed by a CA that the browser trusts then the browser in turn trusts that specific cert. The browser then uses the public key to encrypt a message to the site containing information for encrypting return transmissions to the browser.

The point being, all CA's are on an equal playing field, and fully trusted. The moment any one CA is no longer fully trustworthy or the moment its private key is no longer secure the whole system fails.

Re: Iran forged the wrong SSL certificate

#12

Post by [deleted] » Thu, Sep 01, 2011, 8:49 AM UTC

InclinedPlane wrote: post #11

fletchowns wrote: post #5

How come it's just one CA that is needed to ensure the trust of a domain, especially one as important as *.google.com? It seems like it's only a matter of time before something like this happens again.

The idea is that all CA's are effectively fully trustworthy. The public keys for the CA's certs are loaded into browsers. When a specific SSL cert is created the private key is generated by the buyer (and never revealed) then the public key for that is sent to the CA and signed. In this way a link of trust is created between the CA and whoever bought the SSL cert. Now, when a browser is used to go to a website using…

[deleted]

Re: Iran forged the wrong SSL certificate

#13

Post by robtoo » Thu, Sep 01, 2011, 8:55 AM UTC

We don't know that they didn't get a forged certificate for ssl.google-analytics.com.

Diginotar haven't (AFAIK) released even a partial list of affected domains, other than admitting that there were quite a lot of them.

Re: Iran forged the wrong SSL certificate

#14

Post by mike-cardwell » Thu, Sep 01, 2011, 8:57 AM UTC

I'm not a big fan of handing over the security of my website to third parties by letting them inject arbitrary code into my pages, eg Google Analytics. A lot of people seem to do it without giving it any consideration though.

You have to weigh up the pros and cons I agree. However, do you need that like button which works by including javascript from facebook.com, or can you live without it? Even better, can you do something alternative which allows you to have a like button, but without including third party script?

Re: Iran forged the wrong SSL certificate

#15

Post by oldstrangers » Thu, Sep 01, 2011, 8:57 AM UTC

All this SSL spoofing of late coincides nicely with the adoption of "always on https" by facebook/google/twitter/et al.

Re: Iran forged the wrong SSL certificate

#16

Post by TobiHeidi » Thu, Sep 01, 2011, 8:59 AM UTC

Just by having a forged SSL Certificate for ssl.google-analytics.com how can they supply their javscript ? The request still goes to the google servers and not to any evil-democracy-suppressors.gov.ir

So sure if they could reroute the request to their servers evil things could be done. But they can NOT. Or am i missing something ?

Re: Iran forged the wrong SSL certificate

#17

Post by derrida » Thu, Sep 01, 2011, 8:59 AM UTC

A solution: http://www.convergence.io

Re: Iran forged the wrong SSL certificate

#18

Post by kahawe » Thu, Sep 01, 2011, 9:00 AM UTC

Can anyone explain to me how I can open up a CA and get my CA certs distributed with browsers and JVMs and what not? Is there some sort of "IANA" that approves and manages this and why would they approve all sort of shady CAs which clearly are a dangerous weak link in the whole SSL construct.

Re: Iran forged the wrong SSL certificate

#19

Post by cperciva » Thu, Sep 01, 2011, 9:00 AM UTC

TobiHeidi wrote: post #16

Just by having a forged SSL Certificate for ssl.google-analytics.com how can they supply their javscript ? The request still goes to the google servers and not to any evil-democracy-suppressors.gov.ir So sure if they could reroute the request to their servers evil things could be done. But they can NOT. Or am i missing something ?

I don't think the Iranian government has any difficulty forcing telecommunications companies to install filtering / interception boxes.

Re: Iran forged the wrong SSL certificate

#20

Post by arethuza » Thu, Sep 01, 2011, 9:01 AM UTC

cperciva wrote: post #2

Paging tptacek, please come to the white courtesy phone and explain that SSL is the greatest thing since sliced bread. ;-)

As far as I can see this isn't a fundamental problem with SSL, but the fact that most environments come pre-installed with certificates for CAs that aren't really worthy of trust.

[Edit: Certainly looking through the list of Trusted Root CA certs on this machine I have no idea who 95% of these organisations are - I also have a certificate installed by a proxy so it can intercept any SSL traffic and inspect the contents].