Box 1: Threat modeling -
Threat modeling's motto should be, "The earlier the better, but not too late and never ignore."
Box 2: Static code analysis -
Validation in the CI/CD begins before the developer commits his or her code. Static code analysis tools in the IDE provide the first line of defense to help ensure that security vulnerabilities are not introduced into the CI/CD process.
Box 3: Penetration testing -
Once your code quality is verified, and the application is deployed to a lower environment like development or QA, the process should verify that there are not any security vulnerabilities in the running application. This can be accomplished by executing automated penetration test against the running application to scan it for vulnerabilities.
References:
https://docs.microsoft.com/en-us/azure/devops/articles/security-validation-cicd-pipeline?view=vsts
