What Is CI/CD?

CI/CD is a software engineering practice that combines continuous integration (CI) with continuous delivery or continuous deployment (CD). The goal is to bridge the gaps between operations and development teams by implementing automation across the software development lifecycle (SDLC), including the build, testing, and deployment activities.

Traditional methods integrated a collection of software updates into one large batch before deploying a newer version. However, DevOps practices utilize continuous development, testing, integration, deployment, and monitoring throughout the entire lifecycle. Implementing CI/CD helps facilitate early defect discovery, improve productivity, and achieve faster release cycles.

It involves using automation to take code changes and package them into software deliverables, with automated tests to verify software functionality. Depending on the deployment type, it also involves using automated deployment services to deliver them to end-users.

What Is CI/CD Security?

The CI/CD pipeline is a core component of DevOps, providing the basis for all processes used to build and deliver software. The pipeline also enables collaboration between DevOps teams by creating a unified workflow for development and IT operations processes. A secure CI/CD pipeline extends the DevOps methodology and culture to embrace security.

In many CI/CD pipelines, security tasks are not part of the main lifecycle stages. The DevOps team can build, test, and deploy applications without implementing security practices, leaving security to the end of the pipeline. However, this failure to incorporate security into the CI/CD pipeline increases the risk of vulnerabilities reaching production.

CI/CD security practices help secure applications and reduce the security burden. Managing security as part of the development process makes detecting and resolving issues easier. Addressing security faster and fixing vulnerabilities early in the SDLC also reduces costs because teams don’t have to return later and repeat their work.

The purpose of CI/CD security goes beyond identifying and remediating vulnerabilities—it also emphasizes keeping pace with other CI/CD processes. A secure CI/CD pipeline allows teams to find and fix issues without disrupting the overall CI/CD flow, achieving security without delaying or rolling back software releases.

CI/CD Security Tips and Best Practices

Shift Security Left with SAST

Shifting security left means moving security tasks, primarily security testing and remediation, earlier in the software development lifecycle. In many cases, shifting left gives developers more security responsibilities, such as testing code for vulnerabilities and remediating it. CI/CD pipelines utilize static application security testing (SAST) to achieve this goal.

SAST tools analyze source code to identify security vulnerabilities and weaknesses. Teams can implement SAST during the early phases of the SDLC to find flaws in the source code early when it is easier and more affordable to fix issues. The goal is to prevent critical issues from being released into production.

SAST is a white box technique that analyzes the application from the inside, examining source code, byte code, and binaries. They scan the software even before it is compiled or deployed, ensuring teams can apply these tests early in the lifecycle, get feedback while coding the application, and fix issues as they arise.

Set Up Checks and Safeguards When Committing Code

Teams typically work on projects within an integrated development environment (IDE). Implementing an IDE security plugin during the development phase before checking code into version control is critical to ensure security. These tools analyze code as it is written, alert developers when they potentially introduce a vulnerability, and provide remediation guidance.

In addition to IDE security plugins, it is important to ensure any code written by developers is peer-reviewed using a security checklist like OWASP’s Cheat Sheet Series. Teams can simplify this process by delivering code in small units, which are easier to review manually. It is also easier to detect errors in small units.

Teams should establish controls and rules for committing code into a central repository, such as:

• Use pre-commit hooks for inspecting code.
• Ensure all code meets quality and security standards.
• Never copy sensitive data, like authentication tokens and API keys, to production environments or Git repositories.
• Use secret managers for tokens and API keys.

Use a Network Firewall

Firewalls isolate an internal network from external entities. You deploy a network firewall to inspect all traffic and use rules to allow only the traffic required for your CI/CD tooling. DevOps teams should always deploy CI/CD pipelines behind a firewall.

Deploying additional firewalls can help strengthen a CI/CD environment. It enables teams to practice network segmentation by regulating traffic between development and testing environments, or Kubernetes clusters.

Check Open-Source Vulnerabilities

Open-source software facilitates rapid software development but can introduce vulnerabilities that impact the application’s security even if the code was not changed. A CI/CD pipeline requires open-source software security measures to ensure it does not contain vulnerabilities. It involves checking all imported open-source components and libraries for known vulnerabilities.

Software Composition Analysis (SCA) tools can analyze open source binaries and third-party components, flagging licensing and compliance issues and providing security alerts. Once the team verifies code quality and a CI build succeeds, the pipeline can deploy the application to a testing environment to verify there are no detectable vulnerabilities at runtime.

Diligently Monitor and Clean Up

A CD pipeline requires proper security maintenance. This involves monitoring the CI/CD environment while it runs and terminating temporary resources like virtual machines (VMs) and containers after a task completes. Teams can minimize the attack surface of VMs and containers by removing unnecessary utilities and tools and launching containers in read-only mode whenever possible.

Conclusion

In this article, I explained what it means to create a secure CI/CD pipeline, and provided 5 best practices that can help you create a secure software development lifecycle:

• Shift security left with SAST - implementing automated static code analysis every time code is modified or committed.
• Set up checks and safeguards when committing code - security tooling should be integrated into the IDE to provide fast feedback to developers.
• Using a network firewall - ensuring CI/CD infrastructure itself is secure and preventing unauthorized access.
• Check open source vulnerabilities - scan all components and their dependencies for security weaknesses.
• Diligently monitor and clean up - any virtual machines, containers, or other artifacts left over after the CI/CD pipeline has run increases the attack surface and should be eliminated.

I hope this will be useful as you improve the security posture of your CI/CD environment.