Shift-Left Security with CI Tools
Emphasizing early detection and mitigation of security issues within the software development lifecycle, the shift-left security approach is crucial in addressing the increasing complexity of security, spanning from local infrastructure to cloud environments. This method of tackling security challenges has evolved into a benchmark for assessing the reliability and maturity of your Software Development Life Cycle (SDLC) under many organizations. Continuous Integration (CI) tools play a pivotal and fundamental role in implementing and reinforcing “Shift-Left” security practices within the software development lifecycle as comprehensive CI tools integrate and automate various security tests from container scanning to secret scanning.
Securing the CI tools can present a challenge, and mishandling this process carries the risk of triggering adverse security incidents. This is particularly critical because CI tools have access to a variety of resources, ranging from source codes and databases to secret storages.
Best Practices to Secure your CI tools
Consider these best practices crucial for safeguarding your CI tools and fortifying your Shift-Left Security Foundation. The best practices could be classified into three different categories, Securing Infra configuration of your CI tools, Implement Robust Access Control to CI tools and Consider CI scripts with the same level of importance as your production code.
Securing Infra configuration of your CI tools
Configuring your CI tools properly during deployment is a crucial step in ensuring their security. Below are some common configurations that you should consider adhering to when deploying your CI tools:
Place Your CI Tools Behind a Gateway to Restrict Public Access
In most scenarios, CI tools are deployed within development environments to access resources throughout the Software Development Life Cycle (SDLC). Placing your CI tools behind a gateway ensures that only your organization has access to them.
Ensure Container Images used by your CI tools is secure
Ensuring the security of CI tools’ images is essential for maintaining the overall security of your Continuous Integration (CI) pipeline. Here are some practices to help ensure the security of CI tools’ images.
- Use the image from Ensure that the base images used for CI tools are from reputable sources and have undergone security evaluations
- Install only the necessary components and dependencies in the CI tool images. Avoid unnecessary packages and services to minimize potential security risks.
- Run container scans before deploying
Securing communication between CI tools and other resources
As CI tools need to be granted access to different resources so that it could set up all the components for other tests, we need to ensure the communication between the CI tools and the resource are secure. For example, enforce Use HTTPS/SSL/TLS, enforce network segmentation to isolate the communication channels between CI tools and other resources and add authorization layers between your CI tools and the other resource.
Modifying default credentials for improved security
Some CI tools are set up with some default configuration, for example, default credentials. To remove the default credentials in your CI tools, you need to identify the configuration files or settings where default credentials are specified. This might include configuration files for applications, databases, or any system requiring authentication.
Implement Robust Access Control to CI tools
Once we have set up secure deployment environments for our CI tools, we need to implement a robust access control to the CI tools. When implementing access controls for your CI tools, there are two key aspects to consider. The first involves restricting who can access your CI tools and defining the manner in which access is granted. The second part focuses on limiting the resources that your CI tools are authorized to access.
Restrict access to your CI tools
Follow the principle of least privilege by granting users and systems the minimum level of access required to perform their tasks to avoid assigning overly permissive roles to the users. For example, a developer should be able to view test results under the CI tools but they should not be granted permissions to change and deploy the CI scripts running in the CI tools; The administrator should at least use MFA when accessing the CI tools;. Define roles based on job responsibilities, ensuring that each role has the necessary access without unnecessary privileges.
Restrict the resource your CI tools could access
As previously mentioned, CI tools have access to a diverse range of resources, including source codes, databases, and secret storage. It is imperative to establish accurate and granular role assignments and access controls for CI tools to prevent the assignment of overly permissive roles.
In certain incidents, security breaches targeting CI tools have demonstrated the potential for bad actors to exfiltrate product data. This occurs when CI tools, designed to access only sample data in development or test environments, are granted IAM roles with permissions beyond what is strictly necessary.
To address this, consider the following best practices for restricting CI tool access:
- Apply the principle of least privilege to your CI tools as well to limit the access of the CI tools itself.
- Add authorization layer between the CI tools and the resource.
For example, if you deploy Jenkins CI tools in your cloud environment, you should define a proper IAM policy to the role that the Jenkins Instance should consume and in the Policy, you should only allow the necessary actions.
Consider CI scripts with the same level of importance as your production code.
After you set up secure deployment environments for your CI tools and grant the proper access control to these tools, you would start to write your CI scripts to integrate all the different tests, regression, feature testing and security testing under your CI tools.
In numerous instances, CI scripts are authored by operations engineers or DevOps teams rather than developers. This can lead to certain security checks being less stringent, as there is a perception that these CI scripts are considered internal code. Due to this mis-perception, many security issues could be introduced with your CI Scripts. In order to ensure that your CI scripts adhere to the security standards as you use for your production codes, it is advised to add the following security checks.
Implement Security Reviews and Peer Reviews to review CI Scripts
Establish clear guidelines and roles for security reviews, involving diverse teams in collaborative discussions to assess code against coding standards and security best practices.
Activate All Automated Security Scanning Tools to scan CI scripts
Enable security scanning tools, such as, dependency scanning (SCA), Secret Scanning, SAST Scanning and SBOM against your CI scripts to proactively identify vulnerabilities in your CI scripts during the early stages of the SDLC. It is crucial to enforce actions upon detection of potential security issues by these automated scanning tools after enabling all these automated security scanning. One common issue we’ve observed is the absence of action items, even when the automated scans identify valid security concerns.
Conduct Regular Security Audits and Updates
Perform routine security audits and updates alongside enabling comprehensive security scans during CI script commits. Regular audits are essential to maintain system currency and address security issues stemming from legacy code. For instance, a vulnerable dependency library within your CI scripts could be identified and addressed through these audits.
Establish Robust Monitoring and Logging
Similar to production code, it is important to enhance monitoring and logging for CI scripts, integrate logging directly into scripts, define key metrics for tracking, and leverage built-in tools from your CI/CD platform. Centralize logs for comprehensive analysis, set up alerts to receive immediate notifications for critical events, and regularly review logs for early issue detection.
Conclusion
In conclusion, as technology evolves and the central role that CI tools play in shaping your “Shift-left” security stance, the role of CI tools becomes increasingly crucial in ensuring the integrity and security of software development processes. Fortifying the foundations of “Shift-Left” security for CI tools is paramount in establishing a proactive and resilient security posture under your organization. Emphasizing robust access controls, secure configurations, and regular updates serves as a solid defense against potential threat.By following the best practices outlined in this guide, your organization can effectively mitigate risks, identify vulnerabilities early in the development lifecycle, and cultivate a culture of heightened security awareness.