Recent research in defense mechanisms against wormhole attacks in Mobile Ad Hoc Networks (MANETs) focuses on developing secure, distributed, and lightweight detection techniques to identify malicious tunnels that compromise routing integrity. Wormhole attacks create unauthorized shortcuts between distant nodes, leading to packet interception and route disruption. To counter this, modern approaches integrate cryptographic-hash verification, trust-based detection, and timing analysis within routing protocols to authenticate route discovery and identify abnormal delays. Machine learning and graph-based anomaly detection models have also been employed to differentiate legitimate links from wormhole-induced paths with high accuracy. Cluster-based and localized defense mechanisms further reduce computation and communication overhead by assigning monitoring responsibilities to cluster heads. Recent studies emphasize energy-efficient, real-time, and mobility-aware frameworks that maintain high detection precision while minimizing false positives, ensuring secure and reliable communication in dynamic MANET environments.