Inferring Software Update Practices on Smart Home IoT Devices Through User Agent Analysis

Smart home IoT devices are known to be breeding grounds for security and privacy vulnerabilities. Although some IoT vendors deploy updates, the update process is mostly opaque to researchers. It is unclear what software components are on devices, whether and when these components are updated, and how vulnerabilities change alongside the updates. This opaqueness makes it difficult to understand the security of software supply chains of IoT devices. To understand the software update practices on IoT devices, we leverage IoT Inspector's dataset of network traffic from real-world IoT devices. We analyze the User Agent strings from plain-text HTTP connections. We focus on four software components included in User Agents: cURL, Wget, OkHttp, and python-requests. By keeping track of what kinds of devices have which of these components at what versions, we find that many IoT devices potentially used outdated and vulnerable versions of these components-based on the User Agents-even though less vulnerable, more updated versions were available; and that the rollout of updates tends to be slow for some IoT devices.