If you regularly share snapshots of your life online, turning off geotagging isn’t a very reliable way to keep your location private. Everything seen in the photo — including faint reflections — can be used to figure out where you were with scary accuracy.
Over at Hacker News, there’s an ongoing discussion about an article by IOActive Labs on how simple reflections in windows can reveal more about your location than you were intending to.
In the piece, researcher Alejandro Hernández starts with photos found on Twitter by searching for “hotel view.” Oftentimes the results will be Tweets by the rich and famous showing the gorgeous views from where they’re staying.
Even if the photo doesn’t show the interior of the hotel room, it’s fairly easy to pinpoint a somewhat accurate location based on (1) the buildings seen outside, and (2) the buildings seen in the room’s window reflections.
Using public “open source intelligence” tools such as Google Earth, Google Maps, Google Search, hotel websites, and building information databases, Hernández is usually able to figure out which hotel the photo was captured from, and sometimes even a rough estimate of what floor the photo taker was on. He was able to do this for the photo above:
Hernández writes that he wants to “help people to be more careful when taking pictures through windows because they might reveal their location inadvertently.” What else could reflections reveal? Maybe more than you think:
[...] information disclosed in reflections to develop a profile of an individual. For example, if the person called room service (plates and bottles reflected), what brand of laptop they are using (logo reflected), or whether they are storing something in the safe (if it’s closed or there’s an indicator like an LED perhaps).
If you want to reduce the amount of personal information that could potentially be shared, Hernández recommends eliminating reflections when photographing scenes through windows (either by choosing a different angle or by turning off all lights in the room).
As camera technology becomes more advanced, reflections could play an even creepier role in extracting info from photos. Last December, a research study suggested that reflections seen in eyeballs could help unearth evidence in criminal cases.
Glass Reflections in Pictures + OSINT = More Accurate Location [IOActive Labs]
P.S. If you don’t want your location revealed AT ALL, it’s simply better to not share photos online. Anything seen in your photos can help identify where you were when it was captured. To see how easily this is done, just check out the The View From Your Window Contest. Every week, participants try to figure out where a photo was shot using only the things seen inside the frame. The accuracy of the guesses may surprise you.
Thanks for sending in the tip, Earl!