Missed Opportunities: Measuring the Untapped TLS Support in the Industrial Internet of Things

TL;DR

This paper assesses the global adoption of TLS in industrial Internet protocols, revealing low overall security and identifying gaps in TLS deployment and configuration practices across the Internet.

Contribution

It provides the first comprehensive Internet-wide analysis of TLS support in industrial protocols, highlighting the low adoption rate and security issues in real-world deployments.

Findings

Only 6.5% of hosts use TLS in industrial protocols.

New protocols have higher TLS adoption (7.2%) than traditional ones (0.4%).

42% of TLS-supporting hosts show security deficits.

Abstract

The ongoing trend to move industrial appliances from previously isolated networks to the Internet requires fundamental changes in security to uphold secure and safe operation. Consequently, to ensure end-to-end secure communication and authentication, (i) traditional industrial protocols, e.g., Modbus, are retrofitted with TLS support, and (ii) modern protocols, e.g., MQTT, are directly designed to use TLS. To understand whether these changes indeed lead to secure Industrial Internet of Things deployments, i.e., using TLS-based protocols, which are configured according to security best practices, we perform an Internet-wide security assessment of ten industrial protocols covering the complete IPv4 address space. Our results show that both, retrofitted existing protocols and newly developed secure alternatives, are barely noticeable in the wild. While we find that new protocols have a higher TLS adoption rate than traditional protocols (7.2% vs. 0.4%), the overall adoption of TLS is comparably low (6.5% of hosts). Thus, most industrial deployments (934,736 hosts) are insecurely connected to the Internet. Furthermore, we identify that 42% of hosts with TLS support (26,665 hosts) show security deficits, e.g., missing access control. Finally, we show that support in configuring systems securely, e.g., via configuration templates, is promising to strengthen security.