Swap It Like Its Hot: Segmentation-based spoof attacks on eye-tracking images
Anish S. Narkar, Brendan David-John
TL;DR
This work exposes a new vulnerability in gaze-based iris authentication by introducing IrisSwap, a pipeline that segments an attacker’s eye image and digitally swaps in a victim’s iris texture to defeat liveness detection while preserving gaze signals. By leveraging a shallow-double-UNET iris segmentation (Shallow-net), an inverse rubber sheet-based iris texture swap, and a Pupil Labs gaze-estimation framework, the authors demonstrate offline and online attacks that bypass state-of-the-art liveness detectors with user-level attack success around $0.58$ and $0.55$ respectively. Iris authentication remains exploitable under these conditions, with mean iris-authentication HD around $0.36$–$0.39$ and a substantial portion of victims impersonated, highlighting a pressing need for defenses beyond velocity-based liveness. The findings motivate the development of robust iris-authentication schemes and artifact-based, peri-ocular, or watermarking defenses to counter digital iris manipulation in eye-tracking systems, and they underscore practical security concerns for deploying gaze-based biometric authentication in real-world devices.
Abstract
Video-based eye trackers capture the iris biometric and enable authentication to secure user identity. However, biometric authentication is susceptible to spoofing another user's identity through physical or digital manipulation. The current standard to identify physical spoofing attacks on eye-tracking sensors uses liveness detection. Liveness detection classifies gaze data as real or fake, which is sufficient to detect physical presentation attacks. However, such defenses cannot detect a spoofing attack when real eye image inputs are digitally manipulated to swap the iris pattern of another person. We propose IrisSwap as a novel attack on gaze-based liveness detection. IrisSwap allows attackers to segment and digitally swap in a victim's iris pattern to fool iris authentication. Both offline and online attacks produce gaze data that deceives the current state-of-the-art defense models at rates up to 58% and motivates the need to develop more advanced authentication methods for eye trackers.
