CI/CD Security: Threats, Tools, and Best Practices

Continuous Integration/Continuous Delivery, or CI/CD, is a great way to develop applications efficiently based on a DevOps approach. But by default, CI/CD leaves out one absolutely critical consideration: Security.

For that reason, any organization that uses CI/CD as part of its development strategy must also make CI/CD security a priority. This article offers guidance on how to do that by explaining what CI/CD security means, why it’s important, and which practical steps organizations can take to secure their CI/CD pipelines.

In this article:

What is the CI/CD pipeline?

A CI/CD pipeline is a set of processes that software developers and IT operations teams can use to create applications. CI/CD pipelines typically include the following key stages:

  • Design, which is when developers decide which application architecture to use and which features to implement.
  • Code implementation, during which developers write new source code to implement the application they’ve designed.
  • Code integration, the process by which source code for individual application features or components is integrated into a shared codebase.
  • Build, when source code is compiled to create binaries.
  • Testing, the stage at which compiled code can be tested in a dev/test environment to ensure it works as planned.
  • Deployment, the process through which a newly built application is moved from testing into a production environment.

The goal behind CI/CD pipelines is to integrate these various processes into an efficient, consistent set of operations that DevOps teams can follow. CI/CD helps bring predictability to the development process. It also opens opportunities for automation, since various tools are available to automate many of the operations that take place within the CI/CD pipeline.

What is CI/CD pipeline security?

You might notice that none of the core CI/CD processes described above included security scans, tests, or evaluations. That’s because, traditionally, CI/CD pipelines have focused only on software development and deployment operations, not on security. Application security operations historically took place separately, using a siloed approach.

With CI/CD pipeline security, this changes. CI/CD pipeline security is the integration of security into CI/CD processes, bringing the same types of efficiency and consistency to security processes that CI/CD itself offers to development operations.

Put another way, CI/CD security enables “DevSecOps CI/CD,” meaning the ability to apply the principles behind DevSecOps – a philosophy that emphasizes close collaboration between developers, security teams, and IT operations teams – to CI/CD operations.

The importance of securing your CI/CD pipeline

At a high level, the importance of CI/CD pipeline security boils down to the fact that CI/CD pipelines are the foundation for modern application development and delivery, and baking security into CI/CD processes minimizes the risk of experiencing application security problems.

To be more specific, CI/CD pipeline security is important for the following reasons:

  • By spreading security checks across all stages of the development pipeline – in other words, to shift security both “left” and “right” – it maximizes an organization’s ability to detect and remediate security risks before threat actors exploit them.
  • It reduces the risk of delays to software development and deployment due to security issues that teams don’t discover until later stages of the CI/CD pipeline, at which point updating code to fix the problem is a more complicated and time-consuming process than it would be if engineers detect risks in newly written code.
  • It keeps application development operations in sync with security operations, which helps avoid delays or inefficient processes that might arise if security tests run in a “silo.”
  • It helps to simplify tooling by integrating an organization’s various CI/CD and security tools into a tight-knit suite of solutions – which are easier for engineers to manage than sets of tools that exist in independent silos.

Ultimately, the goal of CI/CD security is to address the various types of security challenges that can arise in CI/CD pipelines, such as those described by the OWASP Top 10 CI/CD Security Risks.

Challenges in securing CI/CD pipelines

While it’s easy enough to recognize the importance of CI/CD pipeline security, actually integrating security into the pipeline can be challenging for several reasons.

Added complexity

The more you try to do as part of a CI/CD pipeline, the more complex your pipeline becomes. Thus, a key CI/CD pipeline security challenge for organizations to solve is finding ways to integrate security into CI/CD without making CI/CD operations too unwieldy or difficult to manage.

Reduced development velocity

Along similar lines, poorly implemented CI/CD pipeline security can reduce CI/CD velocity by slowing down operations. This leads to a longer time in bringing new features to customers, which can in turn trigger a less positive end-user experience and harm a company’s brand reputation.

Multi-faceted application security needs

A holistic approach to application security requires a broad set of tests and controls that can protect against the many types of security risks that may impact applications. As a result, integrating security into CI/CD requires more than just adding a handful of new tests or asking security engineers to meet occasionally with developers.

Tool compatibility limitations

Because application security was traditionally siloed from CI/CD, the degree to which security tools integrate easily with CI/CD pipelines varies. Some tools lack out-of-the-box compatibility with popular CI/CD software, with the result that implementing CI/CD security can be a complex, manual affair.

CI/CD pipeline security best practices

To overcome the challenge described above, consider the following best practices for CI/CD pipeline security.

Optimize CI/CD security for each application

Not every application requires the same types of security checks. To keep CI/CD processes simple and efficient, each application’s pipeline should include only the relevant security tests and scans.

For example, if you’re deploying your app using containers, you’ll want to ensure that container security is a key element of your CI/CD security strategy. But legacy apps that are deployed in other ways don’t require container security controls, and adding them would needlessly complicate the CI/CD process.

Spread security checks across the CI/CD pipeline

Different types of security tests work best when performed at different stages of the CI/CD pipeline. For example, you should scan source code as soon as developers write or integrate it, since at that point, any security flaws in the code are easy to fix. Meanwhile, tests such as Software Composition Analysis (SCA) scans, which check for vulnerable application components and dependencies, should happen after an application has been fully built, because it’s not until that point that you can fully assess all components that factor into an app.

Automate CI/CD security

To the extent possible, the security scans and tests that take place as part of CI/CD security should be automated. In some cases, such as situations where tests reveal insecure configurations, the remediation process can be automated, too.

Some manual assessment and management of security risks is always necessary in most CI/CD pipelines. But the more you automate, the more effectively you can achieve the goals of efficient, consistent security.

Secure CI/CD tools and data

In addition to performing security checks as part of the CI/CD process, a secure CI/CD pipeline should safeguard sensitive data that exists in development tools or repositories. For example, any passwords or encryption keys that developers use to test an application should be stored in a secure secrets manager, rather than hard-coded into CI/CD configurations or scripts.

This is true even in the case of secrets that developers intend to use only for dev/test purposes, since attackers can and sometimes do breach development environments – as they infamously did, for example, in the case of the SolarWinds supply chain attack.

CI/CD security with Aqua

By providing a comprehensive set of application security capabilities that integrate with virtually all major CI/CD platforms and software development tools, Aqua empowers teams to embed security into all stages of their CI/CD pipelines, while keeping development operations fast and efficient. The result is the best of all possible worlds: Highly secure apps on the one hand, coupled with fast, reliable DevOps processes.

The Cloud Native Experts
"The Cloud Native Experts" at Aqua Security specialize in cloud technology and cybersecurity. They focus on advancing cloud-native applications, offering insights into containers, Kubernetes, and cloud infrastructure. Their work revolves around enhancing security in cloud environments and developing solutions to new challenges.