This paper presents the adaptive software security model, an innovative approach integrating the MAPE-K loop and the Software Development Life Cycle (SDLC). It proactively embeds security policies throughout development, reducing vulnerabilities from different levels of software engineering. Three primary contributions-MAPE-K integration, SDLC embedding, and analytical insights-converge to create a comprehensive approach for strengthening software systems against security threats. This research represents a paradigm shift, adapting security measures with agile software development and ensuring continuous improvement in the face of evolving threats. The model emerges as a robust solution, addressing the crucial need for adaptive software security strategies in modern software development. We analytically discuss the advantages of the proposed model.