Static analysis means examining the properties of software without compiling or executing it. This bachelors thesis is a small-scale literature review that attempts by examining and analysing research literature to explore how static analysis can be used to the improve the security of modern web-applications. Based on the literature examined, static analysis security tools (SAST) are able to detect common software vulnerabilities that can have a disasterous effect on businness, and so are able to significantly improve software security. Using these tools effectively in the context of software development however needs planning and technical knowledge.