Luciana Costa

Formal verification of LTE-UMTS handover procedures

Long Term Evolution (LTE) is the most recent standard in mobile communications, introduced by 3rd Generation Partnership Project (3GPP). Most of the formal security analysis works in literature about LTE analyze authentication procedures, while interoperability is far less considered. This paper presents a formal security analysis of the interoperability procedures between LTE and the older Universal Mobile Telecommunications System (UMTS) networks, when mobile devices seamlessly switch between the two technologies. The ProVerif tool has been used to conduct the verification. The analysis shows that security properties (secrecy of keys, including backward/forward secrecy, immunity from off-line guessing attacks and network components authentication) hold almost as expected, if all the protections allowed by the LTE standard are adopted. If backhauling traffic is not protected with IPSec, which is a common scenario since the use of IPSec is not mandatory, some security properties still hold while others are compromised. Consequently, users traffic and networks nodes are exposed to attacks in this scenario.

Formal verification of LTE-UMTS and LTE-LTE handover procedures

Long Term Evolution (LTE) is the most recent standard in mobile communications, introduced by 3rd Generation Partnership Project (3GPP). Most of the works in literature about LTE security analyze authentication procedures, while handover procedures are far less considered. This paper focuses on the procedures that are activated when a mobile device moves between different LTE cells and between LTE and the older Universal Mobile Telecommunications System (UMTS) networks and completes previous results with a deeper formal analysis of these procedures. The analysis shows that security properties (secrecy of keys, including backward/forward secrecy, immunity from off-line guessing attacks, and network components authentication) hold almost as expected in nominal conditions, i.e. when all backhaul links are secured and all backhaul nodes are trusted. The paper also analyses how these security properties are affected by possible anomalous situations, such as a compromised backhaul node or a misconfiguration by which a backhaul link becomes not protected and can be accessed by an attacker. The analysis shows that some security properties hold even in these adverse cases while other properties are compromised. HighlightsWe formally model four handover procedures between LTE-UMTS and LTE-LTE nodes.The standards define some optional security features, and operator can ignore them.All the possible combinations of security policies have been considered.The analysis found vulnerabilities when optional security mechanism are disabled.

Malware Detection and Prevention Platform: Telecom Italia Case Study

This paper illustrates the botnet problem, its impact and the need of security measures. By reviewing the existing literature regarding the botnet detection solutions the paper evidences the important role an ISP could take to better safeguard the user reducing in the meantime the spreading of the botnet phenomenon. The malware detection and prevention platform that Telecom Italia has defined is described. The aim is to minimize the potential harm that bots can inflict upon Internet infrastructure and to provide a detection and notification way to the users when their machines try to access a malware domain or when there is evidence that their computers have been compromised.