We discussed the rampant collection of IMEI earlier, and actually we found something even stranger about apps so casually sending the IMEI: we noticed that a few apps were sending the IMEI to 3rd parties but they didn’t have the permission they needed to access it! This is definitely not supposed to happen. What’s going… Continue reading
The 2019 USENIX Security Symposium includes our study on the use of side and covert channels by apps in order to circumvent the permission system. In addition to our paper, we are writing a series of blog posts to explain our main findings. In this post, the first in the series, we provide the names,… Continue reading
The International Mobile Equipment Identity, or IMEI, is a special number that is tied to every unique mobile phone. It is used whenever the phone is registered on a mobile network. It can also be used to blacklist a phone off of the network, which happens, for example, when it is reported as stolen. Blacklisting… Continue reading
Persistent identifiers are the bread and butter of the online tracking industry. They allow companies to learn the websites that you visit and the apps that you use, including what you do within those apps. A persistent identifier is just a unique number that is used to either identify you or your device. Your Social Security Number and phone number are examples of persistent identifiers used in real life; cookies use persistent identifiers to identify you across websites.
In our work looking at COPPA violations, one company really stood out: Tiny Lab Productions. They currently have 98 games available in the Play Store. Most of these games are in Google’s Designed for Families (DFF) program, which means that the developer is specifically marketing their apps to children under 13. We cited them in… Continue reading
One of the things we noticed when doing our large-scale study of children’s games was that way more apps were accessing location data than were seen actually sending it. In some ways this makes sense—COPPA quite explicitly forbids sending location data without verifiable parental consent, something that our testing framework did not provide. Nevertheless, since… Continue reading
In late February of this year, we received word that an advertising company, ironSource, had obtained a leaked draft of our paper on COPPA violations in Android apps. In that version of the paper, we mentioned them (and their subsidiary, Supersonic) exactly once: in a table of advertising SDKs whose terms of service prohibit their… Continue reading
In our study of kids’ Android apps, we observed that a majority of apps specifically targeted at kids may be violating U.S. privacy law: the Children’s Online Privacy Protection Act (COPPA). In response to this revelation, many companies that we named in our paper have responded by stating that they are not covered by the… Continue reading
As a followup to my previous post, I both emailed CVS and tweeted at them to give them an opportunity to comment on their app’s location-sharing practices: I noticed that your mobile app appears to be sharing my location data with around 40 different third parties. Can you please explain this? Is this a bug?… Continue reading
Recently, we decided to take a closer look at apps in our database that are sharing location data. This is a concern, because it could be used to track someone over time. One app in particular stood out, just based on the sheer number of data recipients. The “CVS/pharmacy” app appears to be sending the… Continue reading