Undocumented Radios Found in Solar-Powered Devices

The US Department of Transportation’s Federal Highway Department has warned highway agencies and infrastructure firms to scan solar-powered highway infrastructure for undocumented radios hidden inside batteries and inverters, a concern highlighted in a 10 September 2025 Reuters report, according to Reuters. Undocumented cellular radios are not necessarily malicious, but could be used for malicious purposes, says Chris Grove of Nozomi Networks.

The piece notes that while the radios may be dormant, they create potential avenues for remote access to critical devices such as traffic signs and other road-side infrastructure. Experts emphasise that radios are common in large-scale infrastructure and can be present by default or due to supplier practices, making hardware inventories and monitoring essential. Some observers warn that a broader geopolitical context, including China’s role in global supply chains, factors into the risk landscape.

The article also discusses how various devices, from weather stations to traffic cameras, rely on radio frequencies and how vulnerabilities in related OT systems have already drawn scrutiny.