Wireless Ad Hoc Networks (WANETs) have attracted considerable attention due to their decentralized nature and flexibility, but they also face critical security challenges. Traditional mechanisms often struggle to cope with the dynamic, distributed, and resource-constrained characteristics of these networks. This review examines the use of fuzzy logic- based techniques to strengthen WANET security frameworks, focusing on their effectiveness in intrusion detection, attack prevention, and network resilience. The literature highlights diverse applications of fuzzy logic, including trusted routing protocols, encryption and decryption of fuzzy matrices, parallel encryption with digit arithmetic of cover text, congestion control and QoS scheduling, multicast key distribution, data division using fuzzy logic and blockchain, malicious node eviction in vehicular ad hoc networks, biometric encryption for IoT, multi-level authentication with fuzzy logic-based quantum key distribution, and fog-based secure IoT architectures. Additional contributions include fuzzy logic applications in random number generation, performance evaluation of encryption algorithms, energy-efficient schemes, multipath routing, web spam detection, data security enhancement, key management, packet-dropping attack detection, and high-speed public-key cryptography. The findings suggest that fuzzy logic enhances WANET security and performance by enabling decision-making under uncertainty, improving attack detection, and optimizing resource utilization. However, challenges such as frequent rekeying, larger key sizes, communication and storage overheads, and network congestion remain, requiring further research for efficient deployment in resource-constrained environments.