Evaluating Lightweight Block Cipher Payload Encryption for Real-Time CAN Traffic

2026-04-13

AI Summary

This work addresses the vulnerability of semantic-classification-based reverse engineering, wherein adversaries infer signal semantics by passively observing plaintext CAN traffic. To mitigate this threat, the authors integrate a lightweight block cipher onto the resource-constrained QT PY ESP32-S2 microcontroller to enable real-time encryption of CAN payloads. The proposed solution preserves the required 100 Hz communication real-time performance while effectively obscuring constant and predictable patterns in the signals—thereby significantly diminishing an attacker’s ability to perform semantic inference through timing analysis, payload distribution statistics, or correlation-based methods. Experimental results demonstrate that the encryption mechanism introduces no disruption to the original message scheduling and substantially reduces the feasibility of passive eavesdropping attacks.

Technology Category

• Computer Vision: Adversarial Attacks & Robustness
• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Machine Learning: Hardware-aware ML

Application Category

• Security and Privacy: Applications of cryptography
• Responsible Web: Measurement, analysis, and circumvention of Web censorship
• Systems and Infrastructure for Web, Mobile and WoT: Energy management for devices in mobile Web and WoT environments

Abstract

This study evaluates the feasibility of integrating lightweight block cipher payload encryption into a real-time embedded controller area network (CAN) node using a QT PY ESP32-S2 microcontroller. This work seeks to determine whether the use of a block cipher can prevent semantic taxonomy-based reverse engineering, which infers signal meaning from unencrypted CAN traffic using observation and statistical analysis. CAN payloads are encrypted using a lightweight block cipher and evaluated through experiments that measure timing impact, payload pattern observability, and correlation-based inference. Results indicate that encryption masks constant values and predictable signal patterns while preserving a 100 Hz transmission schedule. These findings suggest that lightweight payload encryption can reduce passive, observation based inference of CAN signal semantics on resource-constrained hardware with limited timing overhead impact.

Problem

• CAN security
• payload encryption
• reverse engineering
• semantic inference
• lightweight cryptography

Innovation

• lightweight block cipher
• CAN payload encryption
• real-time embedded system
• semantic reverse engineering
• timing overhead