Cellular Threat Detection

Abstract

Cellular Networks have become probably the most used types of networks, due to the explosion in the number of their users. Cellular devices nowadays can be found everywhere. The introduction and rise of the Internet of Things (IoT), further increases the need for cellular access. This high usage of cellular networks makes them a precious target for malicious entities.

The purpose of this thesis is to present ways that these malicious entities use to attack cellular networks, and thus compromise their users’ security and privacy. Based on these attack vectors, possible detection methods are presented. The main objective, however, is to present and implement a detection method, namely a sensor-based one.

Throughout this thesis, the three most used cellular technologies of the past years, namely GSM (2G), UMTS (3G) and LTE (4G), and their main characteristics are described. After a brief presentation of these technologies, some of the known vulnerabilities and attacks that exploit them are described.

Considering these vulnerabilities and attacks, possible detection methods are presented. Subsequently, a complete detection method is proposed, using a cellular threat detection sensor (CTDsensor) that collects cellular logs, analyzes them and generated attack alerts when it detects a cell with an unusually high signal power. The alerts generated are then transmitted to a Security Operations Center, where they are stored, collectively analyzed, and displayed, providing a more complete overview of the cellular landscape.