May 22, 2018

Archives for January 2013

How the Nokia Browser Decrypts SSL Traffic: A "Man in the Client"

Over the past couple of days there has been some press coverage over security researcher Guarang Pandya’s report that the browser on his Nokia phone was sending all of his traffic to Nokia proxy servers, including his HTTPS traffic. The disturbing part of his report was evidence that Nokia is not just proxying, but actually decrypting the HTTPS traffic. Nokia replied with a statement (in the comments section of Pandya’s blog post, and to several news outlets):

We take the privacy and security of our consumers and their data very seriously. The compression that occurs within the Nokia Xpress Browser means that users can get faster web browsing and more value out of their data plans. Importantly, the proxy servers do not store the content of web pages visited by our users or any information they enter into them. When temporary decryption of HTTPS connections is required on our proxy servers, to transform and deliver users’ content, it is done in a secure manner.

Nokia has implemented appropriate organizational and technical measures to prevent access to private information. Claims that we would access complete unencrypted information are inaccurate.

We aim to be completely transparent on privacy practices. As part of our policy of continuous improvement we will review the information provided in the mobile client in case this can be improved.

You can find out more about Nokia’s privacy practices at http://www.nokia.com/privacy.

So, it turns out that Pandya was correct: Nokia is decrypting SSL traffic in their proxy servers. This is not disclosed in their privacy policy, and the somewhat vague assurance of things being done “in a secure manner” is not entirely comforting. Beyond that, the statement gave some other interesting clues. One clue was that this is a feature of the Nokia Xpress Browser, an app that is available for the popular Nokia Lumia phones that run Windows Phone 8. These phones are available from the major US carriers, whereas Pandya’s phone (the Asha) is mostly sold abroad. So I tracked down a Lumia phone, installed Nokia Xpress, and did my own investigation. Results after the jump.

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Predictions for 2013

After a year’s hiatus, our annual predictions post is back! As usual, these predictions reflect the results of brainstorming among many affiliates and friends of the blog, so you should not attribute any prediction to any individual (including me–I’m just the scribe). Without further ado, the tech policy predictions for 2013:

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Turktrust Certificate Authority Errors Demonstrate The Risk of "Subordinate" Certificates

Update: More details have continued to come out, and I think that they generally support the less-paranoid version of events. There continues to be discussion on the mozilla.dev.security.policy list, Turktrust has given more details, and Mozilla has just opened up for public viewing their own detailed internal response documentation (including copies of all of the certs in question). None of this changes the fundamental riskiness of subordinate certificates, or the improvements that should be made to the CA system. It just means that in this case, the failure didn’t progress to a full-blown meltdown.

Today, the public learned of another failure by a Certificate Authority–one of of companies that certifies SSL-encryption for our internet communications. (See the end of this post for a catalogue of our past writing on problems with this “CA” system.) This time, the company Turktrust was revealed to have issued two subordinate certificates (also known as “intermediate” certificates) to entities that should not have had them. Subordinate certificates are very powerful. They give the holder the ability to issue SSL certificates for any domain name as though they have control of the parent CA’s “root” certificate. In this case, Google discovered that one of Turktrust’s previously undisclosed subordinate certificates had issued SSL certificates for the domain gmail.com, and that these certificates had been used to intercept Gmail users’ traffic… somewhere. This is where the details get foggy, but Turktrust has begun to describe their version of events.

There is a less paranoid and a more paranoid way of interpreting what happened.

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