Slashdot Mirror

← Back to Stories (view on slashdot.org)

Researchers Find, Analyze Forged SSL Certs In the Wild

Posted by timothy on from the they're-out-there dept.

An anonymous reader writes "A group of researchers from Carnegie Mellon University and Facebook has managed to get a concrete sense of just how prevalent SSL man-in-the-middle attacks using forged SSL certificates are in the wild. Led by Lin-Shung Huang, PhD candidate at Carnegie Mellon University and, during the research, an intern with the Facebook Product Security team, they have created a new method (PDF) for websites to detect these attacks on a large scale: a widely-supported Flash Player plugin was made to enable socket functionalities not natively present in current browsers, so that it could implement a distinct, partial SSL handshake to capture forged certificates."

12 of 86 comments (clear)

  1. More secure browsing... by Anonymous Coward · · Score: 3, Funny

    brought to you by the Adobe Flash plugin!

    1. Re:More secure browsing... by ChadL · · Score: 2

      Where there is an IT team to provide support using SSL client certificates will prevent (and detect via server SSL logs and client errors) fake certificates.
      When enabled the client will sign (using their client cert, generally with a site-specific internally managed CA) all the communications after the key negotiation finishes, so if there is a middle-man that modified the certificate/keys the server will see the clients signature of the communications as incorrect (as the client and server wouldn't agree on what the communications were) even if the user overrides the SSL certificate warning or an attacker (or employer, or user, or vender) adds a fake/compromised CA to the trust store.
      Doesn't work for sites without a support team to work with users and investigate failures or in cases where the internal CA is compromised, but for the highest of security needs its more effective then using Flash.

  2. Just business doing what business does by Anonymous Coward · · Score: 2, Informative

    Many businesses implement a man in the middle server that allows them to REGEXP the HTTPS searches and connections. Generally its a proxy out with a requirement to accept the certificate which is then applied to your local to the proxy connection, but remotely your handing the company the keys to any accounts/connections used across the board.

    There is a thought of trust your admin not to log your password/financial data etc... Its all quite bizarre but someone thought it was a good idea, or didn't understand the fully risk of the implementation.

    Just business doing what business does when its unbridled and government rules are written by that same business.

    1. Re: Just business doing what business does by EmperorArthur · · Score: 2

      They can't. These are certs that are added by the companies IT department, not certs that ship by default. In some places, like United States libraries, internet filters are mandated. So these places have a few choices, let the public potentially view naughty images via Google image search, downgrade all connections to http, or MITM everything. Guess which one of the three the politicians don't like.

      The big thing those IT departments have to worry about is certificate pinning, which is where the browser stores the actual per website cert, and displays an error if it's changed. This is what Chrome does/is planning to keep people from MITMing Google in particular. I can see both Chrome and Mozilla being proactive, while IE focuses on the corporate clients and if anything becomes less secure.

      --
      So lets pretend that we've just completed writing this code, as opposed to having just completed sabotaging it -Altera
  3. Re:Flash? I removed Flash to avoid problems! by oodaloop · · Score: 2, Funny

    Why would you remove the savior of the universe?

    --
    Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
  4. Bluecoat and other security products by Anonymous Coward · · Score: 4, Interesting

    I'm behind a Bluecoat proxy at work. The software plays man-in-the-middle when I access my mailbox or online bank.
    I never understood where my employer got the right to impersonate gmail or xyz-bank with their own certificates.

    1. Re:Bluecoat and other security products by gl4ss · · Score: 2

      you don't know if they're using it for private business without breaching their telecommunications in a manner which should be( and actually in many western countries is) illegal - no matter if you built the road used for delivering the letter...

      of course you probably don't understand all the possible insider and outsider complications that come from having some personnel (no matter if it's some bofh or you) with expressed ability to read everybodys mail and banking details - and from the ability that they lose totally the possibility of knowing if there's some other mitm happening too. basically any security product your company buys is then supposed to stop you from eavesdropping, so you can't use any of that since you _want_ to eavesdrop and do your own extrajudical investigations into affairs which should be investigated by the police if you suspect foul play..

      but now if they(your employees) suspect foul play relating to their id coming from being hacked.. ..you're the first suspect.

      --
      world was created 5 seconds before this post as it is.
    2. Re:Bluecoat and other security products by Anonymous Coward · · Score: 2, Interesting

      If you're using OS X, a secure outside connection is as simple as:

      ssh -D127.0.0.1:1080 user@machine

      That establishes a SOCKS proxy on port 1080 which tunnels connections to the remote machine. Then change your network settings to point your browser at port 1080.

      I'm pretty sure PuTTY on Windows supports SOCKS proxies, too.

      Warning: if using Firefox you need to disable local DNS resolving (so that the domain name is resolved on the other end). I forgot what the config name is, but Google will help you.

      Of course, you could use some paid VPN service. But they usually require you to install a local client, and I refuse to run any such software unless it's FOSS. The only apps I run are native from the vendor, or FOSS.

      If you really want to be elite, you run OpenBSD and setup an L2TP or PPTP tunnel over IPSec. OpenBSD only recently gained reliable, native L2TP/PPTP support, so I haven't had a chance to play around with that. But both OS X and Windows support that natively, at least as a client. Linux of course requires some kind of convoluted setup. On OpenBSD it should be pretty easy to configure, because they make configuring IPSec a breeze (as in an order of magnitude simpler than OpenVPN, which many consider to be pretty easy). Although, they may not have had time yet to simplify the L2TP/PPTP configuration. In any event, with IPSec+PPTP, it should be much easier to switch it on and off compared to SSH tunneling.

  5. Idiotic slashdotters man... by Anonymous Coward · · Score: 2, Insightful

    You idiots, this guy is presenting about a much larger concern of the overall insecurity of this stupid trust model we call SSL CA Cert and all you morons talk about is how much flash sucks. You guys are fuckin nuts for brains man...

  6. Re:One more reason Flash sucks by 1s44c · · Score: 5, Insightful

    Flash is evil and should be destroyed, I agree. But this story is about how researchers did something cool with flash to detect forged SSL certs.

    In this one case Flash isn't the security issue, it's the useful software helping to find the security issue.

  7. Re:Another foreign PhD at an American University by moof1138 · · Score: 3, Informative

    It's very common for research universities to take students from around the globe. This isn't unique to the US, either. For example, here's some Oxford's PhD students in CS:

    http://www.cs.ox.ac.uk/people/...

    It's a very positive thing, actually. Provincialism doesn't improve research.

    --

    Hyperbole is the worst thing ever.
  8. Not really a good sign by Kirth · · Score: 2

    (Error code: ssl_error_no_cypher_overlap)

    Yes, I turned off all weak ciphers in my browser. Including most 128bit ones.

    --
    "The more prohibitions there are, The poorer the people will be" -- Lao Tse