It is likely that the lenses of your glasses have revealed confidential information on your computer without your knowledge.
The applications of video calls They have multiplied since the early moments of the pandemic and they will continue to be widely known as many teams start working remotely, albeit in more popular applications such as whatsappor others a bit more professional like skype or zoom.
And you’ve probably made video calls in applications like WhatsApp, Skype or Zoom, video calls where you made sure the background is blurred and you tried not to share the screen, but maybe you didn’t realize you were wearing glasses at the time.
And now researchers from the University of Michigan in the US and Zhejiang University in China are warning that the glasses in a video conference they can reveal confidential information through the reflections in their crystals.
In the document distributed via ArXivthe researchers describe how optical emissions from video screens can be reflected by spectacle lenses.
“Our work explores and characterizes viable threat models based on optical attacks using multi-frame super-resolution techniques on video frame sequences.”, the researchers point out.
“Our models and experimental results in a controlled laboratory environment show that it is possible to reconstruct with a 720p webcam to recognize texts on the screen with more than 75% accuracy that are only 10 mm high.‘, they add.
They continue that “the current 720p camera attack capability is often assigned to a font size of 50 – 60 pixels on average laptops”.
Beware of video calls of the future
However, they claim that this technique could access smaller font sizes. while webcams improve their resolutions. They add that “we found that future 4K cameras can see most of the header on almost all websites and some text documents”.
In tests, when the goal was to identify the specific website by the reflection of the glasses, the success rate rose to 94%.
Clarifies that there are a wide variety of factors that can affect the readability of text in the reflection of a video conference participant’s glasses, including the intensity of the ambient light, the brightness of the screen or the contrast of the text with the web pageamong other things.
To avoid this, he points out that there are applications such as Zoom that already provide a video filter in settings within “background and effects”, but other applications such as Skype and Google Meet lack this defense.
The researchers implemented a real-time spectacle blur prototype that can be injected into a video stream and the code on . have left GitHub.