Title | On Securing MAC Layer Broadcast Signals Against Covert Channel Exploitation in 5G, 6G & Beyond |
Publication Type | Conference Paper |
Year of Publication | 2022 |
Authors | Soosahabi, Reza, Bayoumi, Magdy |
Conference Name | 2022 IEEE Future Networks World Forum (FNWF) |
Keywords | 5G mobile communication, 5G security, 6G, compositionality, covert channel, covert channels, Data Exfiltration, Downlink, MAC layer security, machine-to-machine communications, Media Access Protocol, performance evaluation, Protocols, pubcrawl, random hashing, resilience, Resiliency, Scalability, security |
Abstract | In this work, we propose a novel framework to identify and mitigate a recently disclosed covert channel scheme exploiting unprotected broadcast messages in cellular MAC layer protocols. Examples of covert channel are used in data exfiltration, remote command-and-control (CnC) and espionage. Responsibly disclosed to GSMA (CVD-2021-0045), the SPAR-ROW covert channel scheme exploits the downlink power of LTE/5G base-stations that broadcast contention resolution identity (CRI) from any anonymous device according to the 3GPP standards. Thus, the SPARROW devices can covertly relay short messages across long-distance which can be potentially harmful to critical infrastructure. The SPARROW schemes can also complement the solutions for long-range M2M applications. This work investigates the security vs. performance trade-off in CRI-based contention resolution mechanisms. Then it offers a rig-orously designed method to randomly obfuscate CRI broadcast in future 5G/6G standards. Compared to CRI length reduction, the proposed method achieves considerable protection against SPARROW exploitation with less impact on the random-access performance as shown in the numerical results. |
DOI | 10.1109/FNWF55208.2022.00092 |
Citation Key | soosahabi_securing_2022 |