The work is led by Thorsten Strufe and colleagues at KASTEL – KIT's Institute of Information Security and Dependability, with plans to present at the ACM CCS conference in Taipei, funded by Helmholtz’s Engineering Secure Systems topic.

Researchers warn that ubiquitous, invisible WiFi networks could become a widespread surveillance infrastructure, potentially exploited by authorities or criminals without triggering suspicion.

Experts urge early safeguards and encrypted communication to prevent misuse as AI-powered surveillance capabilities evolve.

Open-source tools and public ML models have accelerated exploration of WiFi-based tracking, prompting calls for updated digital rights protections and transparency.

Unlike prior approaches requiring specialized hardware, this technique uses standard WiFi hardware and regular network traffic, making it feasible with existing infrastructure.

Potential applications span elderly care, smart security, disaster rescue, health tracking, and occupancy detection, but safeguards are essential to address privacy concerns.

While recognizing benefits in certain scenarios, experts emphasize responsible deployment and regulation of this technology.

Security concerns are amplified by home router vulnerabilities—weak passwords and outdated firmware—that could create new attack surfaces.

Risks include passive surveillance without cameras or microphones, potential misuse by governments, advertisers, cybercriminals, and broader biometric identification without consent.

The technology detects subtle distortions in wireless signals (CSI) caused by body shape and movement, with machine learning models linking those patterns to people.

German researchers show ordinary WiFi routers can identify individuals through walls with near-perfect accuracy using AI to analyze how radio waves interact with the human body, even when phones are off.

Researchers advocate for stronger privacy protections and safeguards to be included in the forthcoming IEEE 802.11bf WiFi standard, and stress the need for policy and technical responses to mitigate risks.