We all protect our house with keys and locks. We are most probably all aware that locks will not resist to an expert locksmith using lock picking or lock bumping. Last year, three US students demonstrated that we should perhaps also fear our neighbors.
They demonstrated that with some minor signal processing tools, it is easy to extract all the needed information from a digital picture to reproduce the key. The steps are rather simple:
- Take one picture
- Using reference points (from the given type of key, compensate distortion through homography
- Normalize the picture to get a reference size
- measure the pits and valleys
- reproduce the key
They experimented using normal digital cameras, cell phones. the most impressive one is using a 5000mm focal to capture pictures from up to 100 feet. And it worked!
Funny paper that once more demonstrates that the frontiers of security are always moving back.