Hacker News Reader

Comment by rdl | Hacker News Reader

I'm a bit confused why they didn't remove TURKTRUST entirely. It's pretty obvious that they issued to a government under some kind of incentive or coercion, and thus became a MITM threat.

I'm sure every reasonably sized government already has either a root key or an intermediate key, but there should at least be enough penalty when you get caught publicly to deter it -- at least raise the cost of being caught enough that governments won't use their CA powers without fear they might be putting the capability at risk each time.

View on HN

Obviously they don't blacklist the CA because doing so would break the sites of all of their customers. That's a very high-cost action, and the cost is borne by people not involved in the security situation. You do it only in an emergency. The system has an existing mechanism in place: revoke the cert, (though see the post by mrb above which argues that the revocation was done incorrectly).

Longer term, yes: I think looking at punishing TURKTRUST in some way, including revoking their CA, makes sense.

But isn't this exactly a high cost situation? Send a loud and clear message that CAs are entrusted with an enormous level of trust, and they damn well better make sure that their procedures are water tight, at the risk of losing their business overnight.

Maybe "cost" is the wrong metric to argue about. My point was that we have a situation where a bad cert was issued, and the correct treatment for it, barring special circumstance, is to use the process designed to revoke bad certs.

Punishing CAs is a laudable goal, but just immediately revoking a CA will result in worse security.

If TURKTRUST is immediately revoked, then all existing sites using it are toast, despite them not being compromised. That just tells users that SSL errors are not to be trusted, that you should just click through.

Hopefully, they remove TURKTRUST from signing future certificates. That way existing customers continue to work, but they can't do more damage, and the lesson is taught. Although, I don't think that's built-in to the cert system, it'd be a decent addition.

They could give them one month or even three months so their client have time to get their certs replaced, that's not terribly important. But in a broader sense, yes, they were compromised - they had an entity vouch for them that apparently vouched with a blank cheque.

If the CA issues certs like that they actually are compromised.

that logic is always going to apply , meaning effectively, you are never going to be able to remove their CA cert, because its always going to break their customer's sites. So no matter how glaring the security problems a CA is never getting delisted. The PKI model as it exists is broken beyond repair.

https://bugzilla.mozilla.org/show_bug.cgi?id=647959

No, Diginotar had their CA removed from several browsers and went bust https://en.wikipedia.org/wiki/DigiNotar

CA death penalty for someone like TURKTRUST matters to users a lot less than CA death penalty for a global CA like Verisign or Entrust. I'd rather get the policy demonstrated with a regional CA (or ideally a small/enterprise CA) and made clear enough to make all other CAs suitably cautious.

Mozilla removed the CA, rather than just blacklisting the intermediate certificates: https://blog.mozilla.org/security/2013/01/03/revoking-trust-...

We need a solution to this. It comes up every time a ca misbehaves.

How hard would it be to allow a website to have multiple certs? If Turktrust's important customers had redundancy, we could pull less painfully.

Or for less rollout, could browsers acknowledge turktrust only as a root for .tr hosts? That would contain the damage, but probably not hit many legitimate customers.

Then you would just have two attack vectors; compromise either of the private keys and you can be the MITM.

Considering the private keys are probably stored in the same place, I wouldn't consider it an additional attack vector.

You could use the same key and just submit multiple reqs to different CAs. This wouldn't be any worse than having one, and would be a way to have a "backup cert" in case a CA screws up.

You can already MITM if you compromise any CA's private key.

I'm afraid that was my response. I doubt I'll need them, and I'll re-evaluate if I ever do, but as far as I'm concerned TurkTrust is not a valid CA. Here's how on Windows (you can't delete them, they come back with the next CA update):

IE, Chrome & everything else that uses the OS:

  runas /user:Administrator "mmc certmgr.msc" 
  (might also work as another Admin user if you disabled the real Administrator account)

  Expand "Trusted Root Certification Authorities"

  Double-click on TURKTRUST certificate

  Click "Details" tab and "Edit Properties..." button

  Click "Disable all purposes for this certificate"

  Repeat for each TURKTRUST certificate in turn

FireFox/Thunderbird & everyone else that reinvented the wheel:

   Click "Options" -> "Advanced" and choose the "Encryption" tab

   Click "View Certificates" button

   Choose "Authorities" tab

   Click on each TURKTRUST certificate in turn and press "Delete or Distrust"...

It's ridiculous that there are well over 300 trusted root CA certificates distributed with Windows 7. Does anyone have a minimal set for the Western world? I don't want to trust Turkey, or Korea, or China, implicitly by default - I'll decide who I trust as and when I have to.

Isn't Turkey west enough for you ... Or a great west wall should build. ??

It's not whether I think Turkey is "West" or "East", it's more than I just don't interact with Turkish websites - so why should I broaden the attack surface of my browser unnecessarily? I realise that the CA -> domain mapping is a poor approximation, but it's the best we've got.

I have a feeling that _firatto is Turkish ("Firat" is a common Turkish name - I know because I'm Turkish!) so he may have taken offense to what you inadvertently implied about Turkey not being part of "The West". :)

My fault for being lazy and using it as a shorthand for "all countries between longitudes 120W and 30E", give or take a few degrees. No offence intended, I just don't live there!

Istanbul is 28°58'E.

Actually, and first of all I believe -want, feel- as a part of mother earth -Gaia- .. And 'west' refers a vision in my mind. Not a geographical place.

Let me explain my offended part: I'm managing some servers on AWS Ireland zone, I have big list firewall rules, not copied and pasted somewhere else, I started all open, and slowly most of China, Taiwan, Korea, Russia ... being blocked -at least SMTP, SMPTS ports- .

I'm sure there're some Turkish people may be involved cyber crime, But most of computer related people I know of is a hard worker, dependable, honest... This is the point of mine being offended..I don't mind not being included in a political society. And sorry for being offended ..:) PLUR.. Peace Love Unity Respect

I don't think he necessarily meant his comment as a slight against the Turkish people, though perhaps he worded it poorly.

What he is saying makes sense if you generalize it too. Most Turkish people probably don't need their browsers to trust certificates from a Panamanian CA, and most Panamanians probably don't need to trust certificates from a Finnish CA. That shouldn't be taken as suggesting anything negative about Panamanians or Finns; it's all about removing trust relationships that are not necessary for users.

Eh, "western world" is a nebulous term. For example, most people would implicitly refer to Australia as a western country, despite geographically being about as east as Japan (a fully industrialized and modern society).

From my relatively uninformed perspective, I would say that Turkey kind of straddles the line between east and west. They are not a primarily English speaking country, they are not (yet?) in the EU nor would I normally think of them as particularly "Europey" (as I would Switzerland; "Europey" is probably just a measure of how "western Europe" a country is.).

My perspective is probably being influenced by history quite a bit as well: http://en.wikipedia.org/wiki/File:Theodosius_I%27s_empire.pn...

Having just moved from Britain to Singapore, I can tell you that for the people here, Turkey looks very much like a part of Europe.

>>I'll decide who I trust as and when I have to.

Check out Convergence, which sounds like exactly what you are looking for. http://convergence.io/index.html

Thanks for sharing how to do this on desktops.

My frustration is with mobile devices. Given the huge proliferation of devices incl. idevices in recent years, it's annoying that we do not have the same options.

I just tried looking for a way to disable said CA in iOS and can't find a way to do so. Maybe someone else has figured this out. Halp?

Users will not understand that TURKTRUST did something wrong. They just see that Chrome is broken. More abstractly, one of the problems of the CA system is, that no one has any incentive to do the right thing. CAs will try to hide a breach in the chain of trust, since discovering the coverup is no worse for them than discovering the original breach. And blacklisting a CA in a browser will degrade the user experience, so browser vendors are reluctant to do so.

I don't generally like the "strikes and you're out" analogy, but in cases such as this, I find myself favoring a "one strike and you're out" policy. Or zero strikes, if we could force through effective audits.

If nothing else, maybe this would put the fear of [entity] into the organizations in question. The erstwhile incompetent ones. The malicious ones, we just need to give the boot, already.

pretty obvious?

I wouldn't call it fairly obvious, but according to this comment -> http://news.ycombinator.com/item?id=5003707 -> the CAs issued included "*.EGO.GOV.TR," which then created the fake Google certificate. If a government entity got access and then did this, you could establish a link between TurkTrust & the government for creating the CA.

That being said, I'd hope that someone researches and figures out why the certificates were issued, to whom, and for what purpose.

Well, with the help of Google Translate, it appears to be the public transit body of the city of Ankara. If I was an evil government body, I'd ask for my intermediate CA cert to be issued in the name of JohnDoesInconspicuousWidgets.com, not a government organisation.

It's obvious because they issued and discovered it was being used for google.com certs.

If it had been innocuously issued, no one would have attempted to issue google.com certs.

Google is in a better position to detect evil google.com certs in use. There's every reason to suspect other evil certs were issued and in use as well (although google.com is probably the most attractive mainstream target; compromising gmail is important to most intelligence and police agencies).

Reply on news.ycombinator.com