This document summarizes various cross-layer attacks in mobile ad hoc networks (MANETs) and their defenses. It first introduces MANETs and discusses their vulnerabilities to security attacks. It then defines cross-layer attacks as attacks that are initiated at one layer but target another layer. The document surveys different types of cross-layer attacks that have been discovered, including interlayer attacks, denial of service attacks, and attacks against cooperation enforcement tools. It also discusses proposed defense mechanisms against these attacks. Finally, it suggests using particle swarm optimization instead of ant colony optimization to improve detection of cross-layer attacks in MANETs.