## 1 Introduction  
In the present era, vehicles are witnessing a surge in connectivity, establishing links among themselves and with the external environment [1]. V2X, an encompassing term denoting \"vehicle to everything\" encompasses various forms of vehicle communication [2], such as Vehicle-to-Vehicle (V2V), Vehicle-to-Infrastructure (V2I), Vehicle-to-Pedestrian (V2P), and Vehicle-to-Network (V2N). Through these technologies, cars can engage in dialogues with other vehicles, infrastructure elements like parking spaces and traffic lights, mobile applications utilized by pedestrians, and cloud-based services via cellular networks [3]. These advancements hold immense potential for future intelligent transportation systems, as they pave the way for novel ITS (Intelligent Transportation System) services that are currently unavailable [4; 5]. The integration of the Internet of Things (IoT) with V2X communications can provide several advantages, including VANET enhancing connectivity [1], localization performance improvement [6], and designing efficient smart city services [7]. V2X and Mobile Ad hoc Networks (MANETs) share concepts and principles. Techniques, protocols, and algorithms developed for MANETs can be adapted and applied to enhance the security, scalability, and efficiency of V2X communication systems. Leveraging the research and advancements in MANETs can contribute to addressing the unique challenges of V2X networks, including routing, resource allocation, and network management, thereby improving the overall performance and reliability of V2X communications. MANETs consist of a set of mobile nodes connected wirelessly in a self-configured, self-healing network without having a fixed infrastructure. These types of networks offer increased mobility by enabling nodes to move freely and randomly, which makes building a routing table very hard because the network topology varies greatly. Each node behaves as a router in order to forward traffic to other specified network nodes. The basic rules are that a new node, whenever it enters an ad-hoc network, must announce its arrival and presence and should also listen to similar announcement broadcasts made by other mobile nodes. In the MANET context, mobile nodes are characterized by less memory, power, and lightweight features, preventing the implementation of demanding algorithms. OLSR (Optimized Link State Routing) is a protocol based on the periodic exchange of control information [8]. This exchange allows each node to build topological knowledge, allowing it to build its own routing table. While OLSR can be used in various scenarios, including smart cities, there are some considerations to take into account. Security is one of these aspects. Thus, securing the OLSR protocol is motivated by the vulnerability of MANETs to security threats, the criticality of MANETs in various applications, the emerging threats and attack vectors, and the need for practical security solutions. Addressing one of these aspects can help ensure MANET's reliable and secure operation in diverse applications. The core of the OLSR is the selection of Multipoint Relays (MPRs), used as a component of a flooding mechanism. MPRs distribute control traffic messages within the network while reducing redundancy in the flooding process. An OLSR node selects its MPR set in such a manner that all two-hop neighbors are reachable by the minimum number of MPRs. However, if a node is feeding the network false information to others, refusing to cooperate, or manipulating the MPR election process, the network will fail to build an accurate and reliable topology, leading to an unsecured routing process. MANETs are prone to security threats that compromise the confidentiality, integrity, and availability of the network and the information. In the case where a node injects false information, refuses to cooperate, or manipulates the Multipoint Relay (MPR) election process, the network will fail to build an accurate and reliable topology, leading to an unsecured routing process.