This document summarizes security issues related to wireless sensor networks. It begins by defining wireless sensor networks and their applications. It then discusses six main security goals for wireless networks: confidentiality, availability, authentication, integrity, access control, and non-repudiation. The document outlines different types of security attacks in wireless ad-hoc and sensor networks, including active attacks like denial of service, jamming, tampering, and routing protocol attacks, as well as passive attacks like traffic analysis and eavesdropping. It emphasizes that security is a critical concern for wireless sensor networks and concludes by stating the document analyzed challenges and limitations, described various attacks, and discussed future research needed on effective security systems.