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An update on attempted man-in-the-middle attacks
- fragsworth 15y agoThis seems like a very expensive, targeted, specific attack. The perpetrators will likely succeed (or have already succeeded) at breaking into their intended target. Someone high-profile in Iran is probably going to get screwed as a result.
- gst 15y agoThat does not necessarily need to be the case. I don't know how the CA in question works, but for many CAs it's sufficient to be able to receive mails at the postmaster address of the domain in order to receive a certificate. So basically you only need to find a single CA that uses this techniques and which uses a DNS server vulnerable to cache poisoning. Probing all of the CAs may be a little bit of an effort, but it's something even a single individual could manage. I would not find it suprising if this was the technique applied in that case.
- happyfeet 15y agoQuestion: This I believe is a serious issue, but what is the best way to 'reach' out to majority of users in a country? Should/would google display this blog link on top of every google service to alert users in Iran, regardless of browser? My thought is this blog may not even reach out to majority of users, till they get affected by it unless it is 'broadcasted'.
- 0003 15y agoNice anti-IE subtext, google.
- martindale 15y agoYeah, I lol'd.
- willvarfar 15y agoThe amazing thing is that: 1) it doesn't happen more often 2) that anyone noticed Its clearly early days. If they had impersonated a download server, they could have got users to download a spiked copy of the browser itself
- tlrobinson 15y agoThere's also the possibility that it does happen often and no one notices, of course.
- dredmorbius 15y agoMakes me wonder how you'd approach the "how do I find bad certs" problem. You'd think that an entity which, say, scrapes a large portion of the Web on a regular basis ... might be able to detect such things. Meanwhile, there's CertWatch http://certwatch.simos.info/ http://certwatch.simos.info/ and The Convergence Project http://convergence.io/ http://convergence.io/
- jonknee 15y agoIt was easily noticeable thanks to Chrome not trusting it in the first place (which also would have prevented spoofing the download server, though I suspect there's more to protect that than just a key).
- SoftwarePatent 15y agoOuch, DigiNotar is revoked in Chrome? They didn't do anything wrong, someone else pretended to be them.
- pilif 15y agoFor somebody else to pretend to be then, in this case, they need their private key. As a CA, you can't have your private key leaked and then still be trusted by a browser. Or they issued the *.google.com certificate by accident, but if you accidentally issue a certificate as a CA, you can't be trusted by a browser either. IMHO, this was entirely justified.
- birken 15y agoThe only way this attack would have worked is if DigiNotar's private key, whose public key is included in the major CA whitelist in major browsers, signed the domain. So either they did it, or somebody stole their private key. Either way it is very much their responsibility.
- tptacek 15y agoThey're being revoked in Firefox and IE too. Their certs are hopefully going to be worthless soon. The ONE THING you ask a CA to do is NOT LET ITS PRIVATE KEY BE USED FOR EVIL. ONE THING.
- sid0 15y agoAnd Mozilla products and apparently IE. Serves them right. I hope every time such a thing happens the CA gets kicked out and blacklisted for life.
- artursapek 15y agoWow, the security features Chrome used to nullify the attack were just implemented in June. I wonder if that was a reaction to another incident like this, or if it was just good foresight?
- tptacek 15y agoThey ship one of the Big 4 browsers and run the Internet's most popular mail server (and thus biggest TLS target). They're uniquely poised to do things like this.
- waitwhat 15y agothe Internet's most popular mail server It is my understanding that gmail is dwarfed by both Hotmail and Yahoo! Mail.
- Natsu 15y agoThis isn't the first time something like this has happened. I don't know if they did it in response to any one particular incident, but they have every reason in the world to implement something like that.
- mukyu 15y agohttp://blog.chromium.org/2011/06/new-chromium-security-features-june.html http://blog.chromium.org/2011/06/new-chromium-security-featu... > In addition in Chromium 13, only a very small subset of CAs have the authority to vouch for Gmail (and the Google Accounts login page). This can protect against recent incidents[1][2] where a CA has its authority abused, and generally protects against the proliferation of signing authority. [1] http://googleonlinesecurity.blogspot.com/2011/04/improving-ssl-certificate-security.html http://googleonlinesecurity.blogspot.com/2011/04/improving-s... [2] http://www.comodo.com/Comodo-Fraud-Incident-2011-03-23.html http://www.comodo.com/Comodo-Fraud-Incident-2011-03-23.html
- pilif 15y agoIt's a shame that the only real protection against rogue (or compromised) CAs is still to have a whitelist directly in the browser. For Google, this was easy as they control both their domains and their browser, but for everybody else who isn't maintaining a browser, they'd have to fall back to solutions like STS which, don't work if the first connection a user sees is already man-in-the-middle'd
- tptacek 15y agoIE is killing it too, and, as this post points out, so is Mozilla. Sign a Google Mail certificate for Iran? Fuck you. You're done. In the medium term, I think a lot of HN people should also take a hard look at CONVERGENCE.IO. For now, though, it's heartening to see the real power behind Internet trust (hint: it's not Verisign and it's not the IETF) taking this seriously.
- dschobel 15y agoWas the CA definitely complicit in this attack? I always assume that private companies have little recourse at state scales of force.
- tlrobinson 15y agoDoes it matter whether they were complicit or simply compromised? Either way they shouldn't be trusted.
- jbri 15y agoEither the CA was complicit, or they weren't secure. Regardless of which it is, the CA's root certificate is not trustworthy. If they were hacked into, spoofed into giving out a certificate, or raided by special forces and had data physically stolen from their servers, then perhaps they can generate a new key and have that become trusted once they've taken steps to ensure something like this doesn't happen again. But there's no way anyone can trust their old root key anymore.
- stanleydrew 15y agoIt's heartening but it's also not. Surely there have been many other cases of invalid certs being granted for lower profile sites, perhaps by this very same CA, without any of us ever hearing about it. And surely the granter of one of those is still considered valid within many browser/OS configurations. But because this was an invalid Google cert the CA gets shut down. It kind of highlights the difficult problem of when to decide to blacklist a CA in the current model. And for clarity, who/what do you think is the real power behind Internet trust? I've been thinking about it for five minutes and can't come up with a good answer.
- Joakal 15y agoIf you want to verify that you no longer support Diginotar CA, this should give you a warning: https://www.diginotar.nl/ https://www.diginotar.nl/
- lwat 15y agoI get redirected to a non-ssl page ( http://www.diginotar.nl/Default.aspx http://www.diginotar.nl/Default.aspx ) instead, no warning? (Chrome)
- dredmorbius 15y agoI get redirected to http there, but this should show the untrusted CA: https://www.diginotar.com/Products/ExtendedValidationSSL/tabid/622/Default.aspx https://www.diginotar.com/Products/ExtendedValidationSSL/tab...
- the1pato 15y agoI get redirected to http after clicking on the first link, just like you did, but when I visit the URL you posted in Chrome (on OS X), I'm able to view the encrypted page without a warning. I changed the settings in Keychain Access hours ago. Does anyone know what's going on?
- lsh123 15y agoThe (partial) solution to this problem is very well known and is already implemented by SSH and several other packages that rely on public cryptography: 1) When user visits a new site, the certificate is presented to the user for inspection. 2) On subsequent visits, the site's certificate is compared to the one stored in the browser cache. If they are the same, then the connection is made silently. If there is difference, then the new cert is presented to the user for inspection. The only problem is that this would kill user experience for 99% of the users who don't care about security in the first place. Thus, browsers need to do some clever UI tricks (e.g. color the thingy in url bar in a different color, etc.) to indicate potential problem to the user yet make it less intrusive. The bottom line is that the fault is not on the SSL/x509. This infrastructure is not perfect but there is nothing better even in the design. The fault is on the browser developers who are not trying to protect users.
- stanleydrew 15y agoSee tptacek's comments from this thread on the earlier post to see why this may not be a great idea: http://news.ycombinator.com/item?id=2938870 http://news.ycombinator.com/item?id=2938870
- marbu 15y agoThere is a Firefox extension 'certificate patrol' using this aproach, see https://addons.mozilla.org/en-US/firefox/addon/certificate-patrol/ https://addons.mozilla.org/en-US/firefox/addon/certificate-p....
- idlewords 15y agoAnyone know a way to remove DigiNotar as a system root CA in OS X? I spent a few minutes struggling with Keychain to no avail, and couldn't Google my way to useful help.
- dekz 15y agoKeychain -> System Roots -> Search for DigiNotar -> Right click delete. Assert it has been removed by navigating to https://www.diginotar.nl/ https://www.diginotar.nl/
- biafra 15y agoDid you try that and it really removed the CA? Or is it supposed to remove the trust only but keep the entry?
- dekz 15y agoIt removed the entry completely from the Keychain, I am on Lion for reference. Sanity testing by loading the homepage over HTTPS results in a certificate warning on all browsers (Firefox redirected to HTTP).
- sid0 15y agoFirefox uses its own CA store, so you need to remove it there too (or wait for the 6.0.1 update).
- sid0 15y agoFirefox uses its own CA store, so you need to remove it there too (or wait for the 6.0.1 update).
- idlewords 15y agoRight-click delete is not an option on Snow Leopard, for some reason.
- deleted 15y ago[deleted]
- guelo 15y agoDo we really need all those Certificate Authorities that are trusted by the browser? I remember 10 years ago Verisign would spend time verifying a business digging through legal documents, addresses, company officers, notarized docs, etc. Nowadays I'm supposed to trust a bunch of fly-by-night operations issuing certificates for a dollar and a song.
- darklajid 15y agoThere are two sides to that, right? You're building a new startup in (whatever) Bulgaria. Funds are low, but you want to protect your users by using TLS/SSL. That's easy today, but your 'Think of the good old days' line is kind of killing that option. I know that in my early 'put something on the net' days I didn't pay for a certificate because it was just too expensive. Nevermind that the process you seem to expect doesn't scale internationally and that I seriously dislike the US centric bias anyway (too much power in one country, without the privacy laws I consider basic standard).
- losethos 15y agohttp://www.google.com/#hl=en&sugexp=gsih&cp=9&gs_id=q&xhr=t&q=64-bit+operating+system&qe=NjQtYml0IG9w&qesig=yAxwmr8MRUwHitbMPQL8eA&pkc=AFgZ2tlHvqWmOh-scz79OT5v8w8ZJG9GEV76Iwsvhjc7Wtxr0oUssDGfXceQw_WFAU-Xt9hIM5tsH0N86S3URDgcSpvs-Li1Tw&pf=p&sclient=psy&site=&source=hp&pbx=1&oq=64-bit+op&aq=0&aqi=g5&aql=f&gs_sm=&gs_upl=&bav=on.2,or.r_gc.r_pw.&fp=f582e101530810fb&biw=1628&bih=999 http://www.google.com/#hl=en&sugexp=gsih&cp=9&gs... You would think with 6000 downloads, I'd get some emails. Nothing but FBI emails. Something's fucked-up, I agree. God says, "unhappiness suppressed carry bed measure revealing perisheth consolation husband comfortest peradventure asking dimensions weakened Anaximenes notion arrive corners unalterable flour exchanged uncorruptible utmost err limitation inflicted have pleasure orator recalls Alypius fear leads pure hereof abstemious joy approaching foolishly are better unclean neatly haply deprived equinoxes answered want tilde Apostles falsely younger compared excursive Mars distill lessen Hereupon Itself caredst forementioned trustees confusedly strictness counselled joyfulness overwhelmed unquiet gratification "
- ajb 15y agoWhat we need, I think, is for browsers to display the CA as well as the URL. As in, 'DigiNotar certifies that you are connected to gmail'. This won't wholly solve the problem, but it will a) broaden the knowledge that CA's actually exist, and thus the problem of trusting them and b) provide some reputational disincentive to being a bad CA. Unfortunately chrome seems to be headed in the opposite direction, removing the URL bar.
- mibbit 15y agoClick on the padlock, and it tells you all of that. eg "The identity of this website has been verified by Thawte SGC CA."
- ajb 15y agoThanks. However since it didn't even occur to me to do that, it doesn't seem likely that many less technical people will do it.
- edanm 15y agoLess technical people will never understand, much less care, what a CA is. It's hard anything explaining the concept of a URL!
- ajb 15y agoThere are lots of people between 'a HN reader' and 'your grandmother'. There will always be people who don't understand what a CA is; but the more people who do, the more pressure there will be for them to do their job correctly. Also, they don't need to understand the technical details. If every time they go to their bank it says 'connection to your bank certified by verisign', and then one day it says 'certified by <someone else>', then a cautious person will be suspicious, even if they are completely nontechnical.
- dpark 15y agoThere are much better ways to notify users than trying to convince them of the value of monitoring their bank's CA. The browser could simply keep track of the cert and notify the user if it changes unexpectedly. This doesn't require the user to understand anything new, and it still works in the case that the fraudulent cert is signed by Verisign.
- jberryman 15y agoAny word on whether Iranians are still getting this attack? I would love to see some traceroutes to google.com from affected individuals' machines.
- blauwbilgorgel 15y agoDigiNotar's mother company Vasco finally released a press statement. http://www.vasco.com/company/press_room/news_archive/2011/news_diginotar_reports_security_incident.aspx http://www.vasco.com/company/press_room/news_archive/2011/ne... Just incredible: They were hacked and they knew it, then forgot to clean up a certificate the hackers generated. On July 19th 2011, DigiNotar detected an intrusion into its Certificate Authority (CA) infrastructure, which resulted in the fraudulent issuance of public key certificate requests for a number of domains, including Google.com. Once it detected the intrusion, DigiNotar has acted in accordance with all relevant rules and procedures. At that time, an external security audit concluded that all fraudulently issued certificates were revoked. Recently, it was discovered that at least one fraudulent certificate had not been revoked at the time. After being notified by Dutch government organization Govcert, DigiNotar took immediate action and revoked the fraudulent certificate. The attack was targeted solely at DigiNotar's Certificate Authority infrastructure for issuing SSL and EVSSL certificates. No other certificate types were issued or compromised. DigiNotar stresses the fact that the vast majority of its business, including his Dutch government business (PKIOverheid) was completely unaffected by the attack. Maybe directly, certainly not indirectly.
- joelhaasnoot 15y agoFF nightly builds also block the PKIOverheid CA which signs the certificates for key Dutch government websites and services (DigiD). Mozilla is going to have a fun time with Dutch users/Dutch Government/DigiNotar
- khuey 15y agoMy understanding is that what Mozilla is going to ship will not block PKIOverheid. See https://bugzilla.mozilla.org/show_bug.cgi?id=682956#c17 https://bugzilla.mozilla.org/show_bug.cgi?id=682956#c17
- joelhaasnoot 15y agoThis (Dutch) article http://tweakers.net/nieuws/76466/hackers-genereerden-zelf-vervalst-google-certificaat.html http://tweakers.net/nieuws/76466/hackers-genereerden-zelf-ve... quotes the spokesperson for DigiNotar, and he claims "we hope that by end of the week our certificates will be trusted by Google, Mozilla and Microsoft again"
- dunham 15y agoI really wish Chrome would warn me when a site jumps to a new CA or even a new certificate. Last I checked, details on the current certificate wasn't made available to plugins, so I can't easily write it myself.