When you upload a selfie on social media you are putting more information out in the public domain than just your facial appearance. Japanese star Ena Matsuoka found this after she was attacked and molested by a crazy fan outside her home in Tokyo last month. Matsuoka is a member of Japanese pop group Tenshitsukinukeniyomi.
The attacker, Hibiki Sato, who was arrested, told police that he figured out her address from high-resolution selfies she posted on social media.
He zoomed in on the reflections in her eyes and identified the streetscape around her home such as the bus stand. He matched the details with images in Google Street View.
Sato went a step further. He also found out the floor on which Matsuoka lived by analysing the angle of sunlight in the reflection in her eyes.
When she reached her door, Sato grabbed her from behind and covered her mouth with a piece of cloth. He dragged her to a dark corner and molested her. Sato told police that he was a huge fan of Matsuoka.
Experts have warned that high-resolution pictures can reveal important personal information. Researchers at Japan’s National Institute of Informatics revealed in 2017 that flashing the peace or victory sign in photos could lead to fingerprint data being stolen.
The researchers were able to copy fingerprints from photos taken by a digital camera three metres away from the subject.
Last month, Zhang Wei, vice-director of the Shanghai Information Security Trade Association, said that the “scissor-hand” gesture (similar to the peace or victory sign) popular in China could reveal a perfect fingerprint.
Speaking at a cyber security awareness campaign in Shanghai, he said, “A scissor-hand picture taken within 1.5 metres can be used to restore 100 per cent of people’s fingerprints.”