A secure development lifecycle (SDLC) is a methodology that incorporates security practices into each phase of the software development process.
Some of the key things to consider and incorporate into your development lifecycle to make it secure are:
Training and Awareness: Developers need to be trained in secure coding practices and understand the risks and potential vulnerabilities associated with insecure code.
Requirements Analysis: Identify security requirements early. This includes things like how data should be protected, what authentication is required, what level of auditing/logging is needed, etc.
Threat Modeling: This involves identifying and categorizing potential threats to the system. This can help prioritize the areas where security controls are most needed.
Secure Design: Incorporate security into the design of the application. This includes following secure design principles such as the principle of least privilege, defense in depth, and fail-safe defaults.
Secure Coding Practices: Implement code according to the security requirements and guidelines. Use static analysis tools to detect security flaws before the code is deployed.
Code Reviews: Regular code reviews can help identify security vulnerabilities. Automated tools can be used to help with this, but they should be supplemented by manual reviews.
Testing and Verification: Use automated and manual security testing techniques to identify vulnerabilities. This includes unit tests, integration tests, and penetration testing.
Secure Deployment: Implement proper security controls when deploying the application. This includes secure configuration of the server environment and using secure protocols for data transmission.
Incident Response and Recovery: Have plans in place for how to respond to a security incident. This includes having backups to recover from data loss and procedures for how to handle a breach.
Maintenance and Patching: Regularly update and patch the software to fix known vulnerabilities. This also includes maintaining the security of the server environment.