What Is Static Application Security Testing (SAST)?

SAST testing typically happens in the following steps:

1. Select a static analysis tool that can comprehend the underlying software framework and perform code reviews of applications written in the right programming languages.
2. Create the scanning infrastructure and take steps to deploy the tool. This includes setting up access control and authorization, handling the licensing requirements, and procuring required resources such as databases and servers for deployment.
3. Customize the tool and configure it to find additional security vulnerabilities or reduce false positives by updating existing rules or writing new ones.
4. Build custom reports and create dashboards for tracking scan results as you integrate the tool into the build environment.
5. Prioritize high-risk applications and onboard all applications.
6. Analyze and triage scan results to remove false positives, track results, and deploy results to the proper teams for timely remediation.
7. Deliver robust training and the proper governance to ensure development teams employ SAST tools properly. Include SAST and software security touchpoints within the SDLC, and as part of your application development process and into deployment.

There are important differences between SAST and DAST.

Static application security testing (SAST) comes early in the CI pipeline and focuses on bytecode, source code, or binary code to identify coding patterns that are problematic or conflict with best practices. Although modern SAST supports multiple programming languages, the methodology is programming-language dependent.

Dynamic application security testing (DAST) is an approach to black-box testing. Because it requires runtime to scan applications, it is applied later in the CI/CD pipeline. DAST doesn’t depend on a specific programming language, so it is a good method for preventing regressions.

Consider the major differences in DAST vs. SAST:

• ​​SAST scans source code lines for vulnerabilities. In contrast, DAST works solely on the inputs and outputs from a running application and lacks any information about its code.
• Another major difference is speed, in that especially for complex running applications, a DAST tool requires more time to execute, compared to how long the SAST tool takes to scan the source code.

In practice, given the difference between SAST and DAST tools, best practices suggest using both. A SAST tool and DAST tool complement each other, and each finds vulnerabilities the other does not.

Like DAST, interactive application security testing (IAST) focuses on application behavior during runtime. However, IAST analysis takes more of a hybrid approach, combining analysis of internal application flows with scanning and black-box testing. IAST is most beneficial in its ability to connect source code with DAST-like findings. But this also makes IAST both programming-language dependent (as it needs to scan source code) and restricted to being performed later in the CI/CD pipeline.

The SAST vs. SCA comparison is somewhat of an apples-to-oranges analogy. Software composition analysis (SCA) focuses on the application’s third-party code dependencies. SCA tools discover all software components, including all direct and indirect dependencies and supporting libraries. SCA is very useful for applications that use many open-source libraries.

In general, there are several steps to implement SAST:

• Select the cloud or on-premises for the means of deployment. The decision depends on how much control is needed, how much scalability, cost, and other factors.
• Configure and integrate SAST into the SDLC. It’s possible to analyze the source code as it’s compiled, scan it as it is merged into the codebase, run SAST in IDE, or simply add SAST in your CI/CD pipeline.
• Choose the extent of the SAST analysis. A complete SAST analysis is the most comprehensive and lengthy, and consists of a full scan of all applications and their code. An incremental scan analyzes only changed code. A desktop configuration scans code in real time as it’s written.

Customize the process to identify new security flaws or reduce false positives by revising old rules or creating new ones. Prioritize results based on factors such as severity of threat, compliance issues, CWE, responsibility, risk level, or vulnerability.

Incorporating DevSecOps principles into the software development lifecycle enhances both cybersecurity and code quality. Static application security testing (SAST) is a key component of this approach, enabling continuous integration by detecting vulnerabilities early and ensuring secure, efficient coding practices.

• Enhanced security posture: SAST helps identify and address security risks such as SQL injection, XSS, and buffer overflows during the development phase, aligning with OWASP Top 10 recommendations.
• Improved developer workflow: By embedding SAST into continuous integration pipelines, developers can receive immediate feedback on potential issues, reducing the cost and complexity of remediating vulnerabilities.
• Proactive risk mitigation: Regular SAST scans minimize risks associated with insecure Java and JavaScript code, improving the reliability of APIs and other application components.

Integrating SAST into CI/CD pipelines ensures that every code change undergoes rigorous testing. This allows data scientists, security engineers, and developers to collaborate on addressing security risks without disrupting the workflow. Combining SAST with tools like static code analysis platforms streamlines vulnerability detection and resolution.