The Spread of Wi-fi Router Malware Revisited

A study by Hu et al. (2009, PNAS, 106(5)) projected that a targeted malicious attack on Wi-Fi routers could infect a region in two days. The study also argued that the use of WPA security protocol in 60-70% routers would practically prevent such epidemics. This paper revisits their model with current Wi-Fi router data from WiGLE.net and a refined data selection method. We examine the temporality and scale of the malware spread applying these two updates. Despite ≈88% WPA adoption rate, we see a rapid malware spread occurring in a week and infecting ≈34% of all insecure routers (≈5.4% of all) after two weeks. This result is significantly higher than the original study projection. It occurs due to the increased use of Wi-Fi routers causing a more tightly connected graph. We argue that this projected risk can increase when current vulnerabilities introduced and connected devices are considered. Ultimately, a thorough consideration is needed to assess cybersecurity risks in Wi-Fi ecosystem and evaluate interventions to stop epidemics.