"Can Reflections in Eyeglasses Actually Leak Info From Zoom Calls? Here's a Study Into It"
Researchers at the University of Michigan and Zhejiang University have brought attention to how video conferencing participants wearing glasses inadvertently reveal sensitive on-screen information due to reflections in their eyeglasses. The researchers call on further investigation of privacy and security issues resulting from video conferencing. In a paper titled, "Private Eye: On the Limits of Textual Screen Peeking via Eyeglass Reflections in Video Conferencing," the researchers describe how they analyzed optical emanations from video screens that have been reflected in eyeglass lenses. Their research investigates and characterizes viable threat models based on optical attacks using multiframe super resolution techniques on video frame sequences. Their models and experimental results show that it is possible to reconstruct and recognize, with over 75 percent accuracy, on-screen texts at heights as small as 10 mm with a 720p webcam. This corresponds to a font size of 28 pt, which is commonly used for headings and small headlines. The attack capability of today's 720p cameras often maps to font sizes of 50-60 pixels with average laptops. Reading reflected headline-size text does not present the same privacy and security problem as reading smaller 9 to 12 pt fonts. However, as high-resolution webcams become more common, this technique is expected to provide access to smaller font sizes. When the goal was to identify only the specific website visible on the screen of a video meeting participant from an eyeglass reflection, the success rate among the Alexa top 100 websites increased to 94 percent. This article continues to discuss the study on the extent to which emerging webcams may leak recognizable textual and graphical information gleaming from webcam-captured eyeglass reflections.