把 side-channel information 配合上統計方法就可以達到 74% 的正確率：「Phone Hack Uses Sensors To Steal PINs」。
透過 browser 的 javascript 就可以拉出這些資料，然後利用這些資料去猜你的手機 PIN 碼：
Researchers from U.K.-based Newcastle University created a JavaScript app called PINlogger.js that has the ability to access data generated by the phone’s sensors, including GPS, camera, microphone, accelerometer, magnetometer, proximity, gyroscope, pedometer and NFC protocols.
而且當可以多抓到更多資訊時 (像是第二次輸入) 準確度就更高了：
Using a sample set of 50 PINs, researchers found that their script was able to correctly guess a user’s PIN 74 percent of the time on the first try, which increases to 86 and 94 percent success rates on the second and third attempts.
有些瀏覽器有做一些修正，讓 side-channel information 變少，於是難度變高：
As for Firefox, starting from version 46 (released in April 2016), the browser restricts JavaScript access to motion and orientation sensors. Apple’s Security Updates for iOS 9.3 (released in March 2016), suspended the availability of motion and orientation data when the web view is hidden, according to researchers.
Google 則是沒修：
As for Google, it’s unclear what measures have been taken. “Our concern is confirmed by members in the Google Chromium team, who also believe that the issue remains unresolved,” the report stated. Google did not reply to a request to comment for this report.
這攻擊方式頗不賴... @_@