The Privacy BlogPrivacy, Security, Cryptography, and Anonymity

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The Internet is on fire with outrage right now about the security warnings in the Facebook Messenger app. The furor is based on the viral spread of a post on the Huffington Post back in December of last year. The issue has come to the fore because Facebook is taking the messaging capability out of the main Facebook app, so users will have to install the Messenger app if they want to continue to use the capability.

The particular problem is with the warnings presented to users when they install the app on Android. Many articles are describing this as the “terms of service” but the warning are the standard text displayed by Android based on the specific permissions the app is requesting.

Here are the warnings as listed in that original the Huffington Post article:

  • Allows the app to change the state of network connectivity
  • Allows the app to call phone numbers without your intervention. This may result in unexpected charges or calls. Malicious apps may cost you money by making calls without your confirmation.
  • Allows the app to send SMS messages. This may result in unexpected charges. Malicious apps may cost you money by sending messages without your confirmation.
  • Allows the app to record audio with microphone. This permission allows the app to record audio at any time without your confirmation.
  • Allows the app to take pictures and videos with the camera. This permission allows the app to use the camera at any time without your confirmation.
  • Allows the app to read you phone’s call log, including data about incoming and outgoing calls. This permission allows apps to save your call log data, and malicious apps may share call log data without your knowledge.
  • Allows the app to read data about your contacts stored on your phone, including the frequency with which you’ve called, emailed, or communicated in other ways with specific individuals.
  • Allows the app to read personal profile information stored on your device, such as your name and contact information. This means the app can identify you and may send your profile information to others.
  • Allows the app to access the phone features of the device. This permission allows the app to determine the phone number and device IDs, whether a call is active, and the remote number connected by a call.
  • Allows the app to get a list of accounts known by the phone. This may include any accounts created by applications you have installed.

This strikes me as more an inditement of the over broad requests for permissions by apps in Android than any particular evil intent on Facebook’s part. Obviously many of these things would be very bad indeed, if Facebook actually did them. After significant searching I have not seen any suggestion at all that Facebook is or is likely to do any of these things without your knowledge.

Many articles are ranting about the possibility that Facebook might turn on your camera or microphone without warning and capture embarrassing sounds or images. Doing so would be disastrous for Facebook, so it seems very unlikely.

After reviewing the actual Facebook privacy policies and terms of service in the Messenger app, I don’t see any sign that these actions would be permitted but of course Facebook does have the right to change the policies, basically at will.

Don’t take from this that I am a Facebook apologist. Anyone looking back through this blog will see many cases where I have criticized them and their actions (here, here, here, here for example). There are major problems with the amount of data Facebook collects, how they collect it from almost everywhere on the Internet (not just their website or apps), and their privacy policies. I have turned off location tracking for the Messenger app on my iPhone because I don’t want Facebook tracking that.

However….. Facebook is not going to start turning on your camera at night to take naked pictures of you! There is a lot about privacy on the Internet to worry about, lets stay focused on the real stuff rather than these fantasies.

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Standard-Profile-Picture.jpgIn episode 21 of our podcast for July, I talk about:

  • A decision giving Canadians more rights to Anonymity
  • Iraq’s recent blocking of social media and more
  • Iran’s outright criminalization of social media
  • A court decision requiring warrants to access cell tower location data
  • Another court stating that irrelevant seized data needs to be deleted after searches
  • A massive failure of data anonymization in New York City
  • A court requiring a defendant to decrypt his files so they can be searched
  • The Supreme Court ruling protecting cellphones from warrantless search.
  • Phone tracking streetlights in Chicago
  • And a small change for iPhones bringing big privacy benefits

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PrivacyPodcastGraphicIn episode 16 of the Privacy Blog Podcast for January, Twenty Fourteen I talk about:
Biological Advanced Persistent Threats
The Apps on your mobile devices that may be enabling surveillance
Why you may soon know more about how much information your service providers are revealing to the government
The total compromise of the TorMail anonymous email service
How the British government is using pornography as a trojan horse for Internet Censorship.
And finally why continued use of a deprecated cryptographic signature algorithm could undermine the security of the Web

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Standard Profile PictureThis is episode 14 of the Privacy Blog Podcast for November,2013.
In this episode I talk about:
How your phone might be tracked, even if it is off
The hidden second operating system in your phone
Advertising privacy settings in Android KitKat
How Google is using your profile in caller ID
and the lengths to which Obama has to go to avoid surveillance when traveling.

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OS News has an interesting article: The second operating system hiding in every mobile phone

It discusses the security implications of the fact that all cell phones run two operating systems. One is the OS that you see and interact with: Android, iOS, Windows Phone, BlackBerry, etc. The other is the OS running on the baseband processor. It is responsible for everything to do with the radios in the phone, and is designed to handle all the real time processing requirements.

The baseband processor OS is generally proprietary, provided by the maker of the baseband chip, and generally not exposed to any scrutiny or review. It also contains a huge amount of historical cruft. For example, it responds to the old Hays AT command set. That was used with old modems to control dialing, answering the phone, and setting up the speed, and other parameters required to get the devices to handshake.

It turns out that if you can feed these commands to many baseband processors, you can tell them to automatically and silently answer the phone, allowing an attacker to listen in on you.

Unfortunately the security model of these things is ancient and badly broken. Cell towers are assumed to be secure, and any commands from them are trusted and executed. As we saw at Def Con in 2010, it is possible for attackers to spoof those towers.

The baseband processor, and its OS, is generally superior to the visible OS on the phone. That means that the visible OS can’t do much to secure the phone against these vulnerabilities.

There is not much you can do about this as an end user, but I thought you should know. 🙂

Lance Cottrell is the Founder and Chief Scientist of Anonymizer. Follow me on Facebook and Google+.

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The Chaos Computer Club (CCC) in Germany recently announced its successful bypassing of the new iPhone 5S fingerprint scanner.

Despite many media claims that the new scanner worked on deep layers in the skin, and was not vulnerable to simple fingerprint duplication, that is exactly what succeeded. 

The CCC used a high resolution photo of a fingerprint on glass to create a latex duplicate, which unlocked the phone. It strikes me as particularly problematic that the glass surface of an iPhone is the perfect place to find really clear fingerprints of the owner.

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ZDNet has published a nice article on 4 key privacy settings under iOS 7 that have defaults you might want to change. Mostly related to location information.

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Infosec Institute published an article showing in detail how application signing on Android devices can be defeated.

This trick allows the attacker to modify a signed application without causing the application to fail its signature check.

The attack works by exploiting a flaw in the way signed files in the .apk zip file are installed and verified. Most zip tools don’t allow duplicate file names, but the zip standard does support it. The problem is that, when confronted by such a situation the signature verification system and the installer do different things.

The signature verifier checks the first copy of a duplicated file, but the installer actually installs the last one.

So, if the first version of a file in the archive is the real one, then the package will check as valid, but then your evil second version actually gets installed and run.

This is another example of vulnerabilities hiding in places you least expect.

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