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39

What makes Superfish, and similar products (all herein just referred to as "Superfish"), different from corporate MitM is that Superfish is doing the MitM on the client machine. Corporate MitM is performed on a separate server or appliance. This is important because the system performing the MitM must have the private key of a Trusted Root CA in order to ...


20

The entire point of SSL is its resistance to eavesdropping by man-in-the-middle attacks like the one you're proposing. If you cannot make the client device trust your self-signed certificate, then your only options are: Intercept an initial HTTP request and never let the communication be upgraded to HTTPS (this will not work if the site has an HSTS record ...


8

Any suggestions? Is is doable? You need to own a certificate trusted by the device to intercept the traffic. How this can be achieved depends on how proper and open the certificate validation on the device is. The device might have a buggy or non-existing validation of certificates. This is typically No validation at all, in which case you could use ...


7

Hopefully, someone will do the testing and give a definitive answer for Kaspersky for you. Meanwhile, here's an answer for the general case: It depends. Does running an SSL proxy against yourself weaken your security posture? Certainly. Will any given product weaken your security posture as bad as Superfish? That's very implementation-dependent, and also ...


6

While your question, why are there so many servers offering export ciphersuites, is valid, your description of the problem is in error. FREAK is: a class of client-side bugs exploitable due to server-side configuration. The vulnerable devices you list are not configured to use export-grade ciphersuites, but they can be tricked into using export-grade key ...


5

These keys are still active because like so many other things the web is fundamentally broken for the purposes of backwards compatability. Technology vendors are quite often stuck with the choice between doing the right thing and supporting what is out there already. Could you imagine the uproar against Google and Apple if they shipped a web browser that ...


4

The main difference between Superfish and a Corporate Proxy is how the new SSL certificate is generated. In the Superfish case, the CA certificate and the private key stands on the client computer, and the software generates a new SSL certificate with a key it have on itself. The traffic is intercepted locally, a new certificate is generated on the client, ...


4

Your problem is a common problem in security know as authentication. Checksum solves the problem of integrity, you know that what you just downloaded is correct, but you do not know from who it comes. If someone is operating a MitM attack, they obviously will try to replace the checksum of whatever download you required with the checksum of the binary they ...


3

There are many servers which support export-grade ciphers simply because default cipher sets had, and in some cases (inexplicably) continue to have them enabled. One of the changes in TLS 1.1 (section A.5) was to state that export grade ciphers MUST NOT be used in TLSv1.1. TLS 1.0 (section D.4) leaves it up to the implementation to decide on the required ...


2

In this case, cert 1 is known as the root certificate. You download it and install it from the university's website. The server certificate is cert 2, which is what the university's website presents to your browser at every visit. cert 1 is used to sign cert 2. When you connect to the university server through SSL, you will be presented with cert 2 and your ...


2

I think the basic idea here is "unauthorized access." If the school accessed a student's non-school account, there can be a case made for the school accessing that account without authorization. There are a couple things that could negate matters: The account is a school account - the school is authorized because it is their account The network access ...


2

In the most simple and insecure case, both the file and the checksum are served via a plaintext protocol like HTTP or FTP. In this case, no, there is nothing to prevent Man-in-the-Middle modification of both the file and the checksum. Your first question, though, was, "Why do some processes rely on published checksums?" The answer is that, if properly ...


2

When you are under an MITM attack, typically the attacker has complete control of part of the link between you and your intended destination. For this reason, it is usually difficult to "bypass" MITM, if done correctly, because the attacker is fully in control of your traffic and free to direct it to wherever he pleases. The attacker can basically just ...


2

No. This is the point of SSL, to prevent this kind of unauthorized snooping. To authorize your proxy you need to tell the device to trust the proxy certificate, and tell the device clients to trust your certificate or use the devices private key, which it sounds like you don't have access to. For more information: ...


2

No, the very nature of HTTPS is that the certificate is required to decrypt it. You could sniff the traffic, but it would be encrypted and useless to you.


1

Take a Look at the FREAK tls vulnerability. you should be able to inject data into the SSL negotiation to trick the device into a RSA Export cipher, and from there the decryption of traffic by a man in the middle is significantly easier ( aka possible. ) Charles is written in java, shouldn't be too hard to modify to exploit this automatically.


1

I would have to say that if you have a privacy concern then you should not be using devices which you see as compromised or risky, the onus is on you to do this. Would you do a bank transfer by giving your details to your worst enemy and asking them to do it ? I have had employers which have essentially blocked Internet access off to prevent this The ...


1

HTTP protocol For HTTP this could be generalized to How does webserver hosting more websites knows which one to host? This is through technique called Virtual Hosting in which browser appends Host header to every request send and webserver serves the content of the wanted site, deciding via the header. So if I host foo.com and bar.com on the same ...


1

If the request to your domain is HTTPS (e.g. https://example.com) this is effectively immune to a MITM attacker (corporate proxy issues aside). If an attacker redirected example.com to the IP of their own site then their own site would not have a trusted certificate installed for example.com so the user would get browser warnings and would be strongly ...


1

To answer your questions: I would imagine that either the router is just set up that way to be convenient, and so that you can contact help if the thing isn't working. That's my theory, I really have no idea why you would do such a thing. It sounds like a bad security practice to me, but also a purposeful choice. You really shouldn't be doing your bank ...


1

For proxying, it is possible to use Burp for android: https://systemoverlord.com/blog/2014/07/13/passing-android-traffic-through-burp/ (this second set of instruction assumes you are using an emulator) http://resources.infosecinstitute.com/android-application-penetration-testing-setting-certificate-installation-goatdroid-installation/


1

Alice sends hello to Bob which contains a code A. Eve intercepts the message and instead puts a code E. The above just won't happen. before Alice sends anything, Alice requests the CA to verify bob.com(Eve), the response from CA won't match Eve, so Alice will receive a warning saying that Bob's certificate is invalid. If somehow Alice has Eve's ...


1

You should not use this in any production system, period. You're trying to design cryptographic primitives, which is something which is extremely easy to get horribly wrong. If you aren't yourself a cryptographer, don't try to design cryptographic algorithms - perfectly good ones already exist. (In general, you should use well-tested systems wherever you can ...



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