Bit-Flipping Attack Exploration and Countermeasure in 5G Network

TL;DR

This paper explores the vulnerability of 5G networks to bit-flipping attacks, demonstrating their feasibility on an open-source platform and proposing a keystream shuffling defense to enhance security without extra overhead.

Contribution

It is the first to analyze bit-flipping attacks on 5G systems and introduces a novel keystream shuffling countermeasure to improve data integrity security.

Findings

Bit-flipping attacks can successfully alter encrypted 5G messages.

The proposed defense raises the difficulty of targeted modifications.

Security enhancements are necessary for 5G to prevent such integrity attacks.

Abstract

5G communication technology has become a vital component in a wide range of applications due to its unique advantages such as high data rate and low latency. While much of the existing research has focused on optimizing its efficiency and performance, security considerations have not received comparable attention, potentially leaving critical vulnerabilities unexplored. In this work, we investigate the vulnerability of 5G systems to bit-flipping attacks, which is an integrity attack where an adversary intercepts 5G network traffic and modifies specific fields of an encrypted message without decryption, thus mutating the message while remaining valid to the receiver. Notably, these attacks do not require the attacker to know the plaintext, and only the semantic meaning or position of certain fields would be enough to effect targeted modifications. We conduct our analysis on OpenAirInterface (OAI), an open-source 5G platform that follows the 3GPP Technical Specifications, to rigorously test the real-world feasibility and impact of bit-flipping attacks under current 5G encryption mechanisms. Finally, we propose a keystream-based shuffling defense mechanism to mitigate the effect of such attacks by raising the difficulty of manipulating specific encrypted fields, while introducing no additional communication overhead compared to the NAS Integrity Algorithm (NIA) in 5G. Our findings reveal that enhancements to 5G security are needed to better protect against attacks that alter data during transmission at the network level.