CAT | Location
CNET’s Declan McCullagh reports on Microsoft restricting access to their Wi-Fi geolocation database shortly after this CNET article describing how to track devices using such databases. I have written about these databases before here, here, and here. Specifically Microsoft is preventing users from querying for the location of a single Wi-Fi device by specifying just one MAC addresses. Prior to the change it was possible to track an individual phone or laptop by querying for the location of that device’s MAC address.
CNET describes a test where they were able to track a device as it moved around Columbus Ohio. This would indicate that the underlying database is updated in near real time, and that it is collecting on mobile devices as well as on the fixed Wi-Fi base stations it is supposed to catalog for enhanced location services.
Tracking mobile devices can only harm the accuracy of enhanced GPS location services because they move around and could potentially give misleading information. It would be easy to eliminate such devices from the database because the type of device is discoverable from the MAC address they are collecting.
While there is no reason to track mobile devices for enhanced GPS, there are all kinds of less savory reasons to gather and track this kind of information. I note that Microsoft’s solution is to prevent access to this individualized tracking information about mobile devices rather than to stop collecting it…..
Last week I did an interview on a San Diego news program about issues with many cameras and smart phones in particular embedding very accurate location information in your pictures. If your camera (smart phone or whatever) has GPS, then the EXIF meta data in the picture will contain your location to within about 20 feet. This can be disabled, but is typically on by default.
While this can be useful when you are trying to sort and organize the pictures on your computer, the risk shows up when you start to share the pictures. By combining date and time information in the pictures I can tell if they are recent. If you are on vacation and posting on the road, an attacker can tell that you are away from home and your home probably unguarded. Pictures of your home and family can provide the exact location of your house as well.
The good news is that major sites for sharing pictures like Facebook and Flickr seem to strip out that information from the photos. It is unclear if that is intentional or just a byproduct of how they are processing and displaying the images. In any case, the data is certainly available to the sites themselves.
I strongly encourage everyone to download an EXIF editor to be able to strip this information from pictures before uploading, and to turn off location tracking in their cameras and mobile phone photo applications to prevent the capture of that information in the first place.
The story is about a german politician Malte Spitz who sued to obtain the retained cell tower records for his own phone, then provided them to the newspaper. The newspaper has created a nice map and timeline tool to allow you to play Spitz’s movements over 6 months. The resolution is impressive and should be a real wake up call about the level of detailed information being gathered on us all.
Of course, if the phone company was capturing GPS or WiFi based location information the data would be much more accurate. While GPS would quickly drain the battery, many modern phones have WiFi enabled all the time, so that information would be readily available without any additional impact on the phone’s performance.