Patrick Weich, Oleg Lobachev

2025Computer Science Research Notes

DOI: 10.24132/csrn.2025-31

Abstract

It is crucial to improve smartphone security, given the prevalence of sensitive information stored on them. This study presents an attack strategy that reveals smartphone PIN entries using computer vision and pattern recognition techniques. By leveraging modern segmentation and hand skeleton tracking, our method accurately identifies and analyzes finger movement patterns, even when partially obscured. We can reliably infer the entered PIN by combining these movement patterns with the smartphone’s position and the on-screen keypad layout. This approach significantly enhances shoulder-surfing attacks, requiring only a video recording of the entry process. Our attack requires much less specialized expertise, making it more accessible. We conclude by analyzing the method’s potential impact and its implications for public safety.

Citation format

WEICH, Patrick; LOBACHEV, Oleg. PIN-a-Boo: Revealing smartphone PINs via segmentation and hand skeleton tracking from video feeds. Computer Science Research Notes, 2025.