Mastering SAST: The 2024 Comprehensive Guide To Static Application Security Testing

Static application security testing (SAST) solutions provide organizations with peace of mind that their applications are secure.

But SAST platforms differ from each other.

A SAST tool that meets developers where they are can make AppSec team’s lives much easier, and significantly enhance the organization’s ability to defend itself from code vulnerabilities in the SDLC.

This comprehensive guide covers all aspects of Static Application Security Testing, on your journey to choosing a SAST tool and vendor.

Read on, at the end of this guide you’ll be able to intelligently choose a comprehensive enterprise-grade SAST solution that builds dev trust while eliminating tension between AppSec teams and developers.

Static Application Security Testing (SAST) Basics

What is SAST?

Static Application Security Testing (SAST) is a type of security testing that analyzes source code, byte code, or application binaries to identify potential security vulnerabilities.

By detecting vulnerabilities early in the development process, SAST enables remediating them before they risk the entire application and become more costly and complex to fix.

SAST tools work by scanning code, analyzing the code’s structure and data flow and detecting security vulnerabilities that could be exploited by attackers. Then, SAST tools then generate reports detailing these potential vulnerabilities, ranking them by severity and providing developers and security teams with guidance for remediation.

SAST vs DAST (Dynamic Application Security Testing) is a common comparison.

Unlike DAST, SAST is performed without executing the program, whereas DAST analyzes applications at runtime.

Static Application Security Testing Role in Secure Development Lifecycle

Why is SAST important in the SDLC?

Integrating SAST in the SDLC helps develop secure software.

The main benefits of making SAST part of developer workflows include:

• Early Detection of Vulnerabilities – By analyzing the source code before it’s compiled and run, developers can detect and fix security issues before they risk the running application. This also makes them less expensive and time-consuming to fix.
• Improved Code Quality – Regularly scanning the codebase with SAST helps maintain high security and quality standards throughout the development process. SAST tools encourage developers to write more secure code from the start, reducing the likelihood of vulnerabilities and creating a security standard across the organization.
• Integration with Development Tools and Processes – SAST tools can be integrated into IDEs, CI/CD pipelines, version control systems, and more. This integration allows for immediate feedback and a streamlined remediation process. It also encourages adoption by developers, since it makes SAST part of their day-to-day rather than a frictional process.
• Regulatory Compliance and Risk Management – SAST helps organizations meet regulatory requirements by ensuring that code is analyzed and vetted for security before deployment.
• Facilitating DevSecOps Culture –  Strategies for SAST integration in the SDLC promotes collaboration between the development, AppSec, and operations teams. This helps break down silos and fosters a culture where security is a shared responsibility.
• Building Developer Trust – SAST tools empower developers to take ownership of the security of their code. They can identify and understand security issues as they work, incorporating security thinking into their daily tasks.

SAST and DevSecOps CI/CD

SAST tools can be integrated directly into the CI/CD pipeline with tools like Jenkins, Bitbucket, CircleCI, and others.

Enabling “shift left” security approach means that every time code is committed and a build is triggered, the SAST tool automatically scans the code for potential vulnerabilities.

As a result, developers get immediate feedback on any security issues discovered, and at the pace of their development.

Integrating SAST into CI/CD pipelines also fosters collaboration between development and security teams, which is a pillar of DevOps and DevSecOps.

When SAST is part of the CI/CD pipeline, security becomes a visible and shared concern.

Developers are empowered to address security issues, AppSec teams can understand what is required of developers to fix them and DevOps can ensure fast, secure and quality deliveries.

This enhances communication and cooperation between developers, AppSec and DevOps teams.

6 Benefits of Static Application Security Testing

SAST tools provide CISOs, Heads of AppSec, DevOps, developers and all stakeholders with multiple benefits.

The main ones include:

1. Affordability and Efficiency

Early Fixes – Identifying and resolving vulnerabilities early in the development process is less costly than addressing them post-deployment.

If issues are identified in production, they might require complex patches, hotfixes, or even architectural changes.

Enhancing Developer Productivity – SAST tools can be automated and integrated into the existing development and CI/CD pipelines, providing real-time feedback to developers.

This automation allows developers to focus on fixing issues rather than finding them.

Over time, regular feedback from SAST tools educates developers about security best practices, leading to better coding habits, which enhances developer productivity.

Secure Applications – By improving security, SAST helps avoid the potentially high costs associated with a security breach, including fines, legal fees, compensation, and the indirect costs of lost trust and damaged reputation.

2. Shift Left: Integration into Early SDLC Stages

Integrating SAST into the early stages of the SDLC is a strategic approach that aligns with the “shift left” application security concept.

By identifying vulnerabilities at the earliest point possible, organizations can prevent potential security issues, rather than having to remediate them after they’ve been exploited.

This proactive approach significantly reduces the risk of security incidents, reduces costs, and increases code quality.

3. No Test Cases Required

SAST tools analyze the source code directly.

They don’t need the application to be running or any specific test cases to execute.

This is unlike DAST or manual testing, which require a running application and carefully designed test cases that simulate various conditions and user behaviors.

As a result, SAST tools:

• Save time and effort in test preparation and execution.
• Provide a comprehensive approach, since they are not not limited by the scenarios that test cases cover.
• Are easier to use for developers.

4. Testing Complex Applications

SAST tools deeply inspect all layers of the application, including backend services, APIs, and third-party libraries.

They are also designed to handle large amounts of code, support a wide range of programming languages and frameworks, and analyze the relationships and data flows between components.

This comprehensive SAST analysis supports the testing of complex applications, which enhances the organization’s security posture.

5. Scan Everything with Ease

SAST tools automatically scan the entire codebase, third party modules and can even be integrated into CI/CD pipelines.

As a result, the scanning process requires minimal human intervention, allowing teams to focus on addressing the issues rather than finding them.

SAST and Compliance

Organizations are increasingly required to adhere to strict compliance regulations and requirements concerning data protection, privacy, and secure software development.

Examples of such regulations include PCI DSS, HIPAA and FISMA. By running SAST scans, analyzing the results of the scan, prioritizing and then remediating vulnerabilities and then re-testing the code, organizations can ensure applications are secure and compliant with regulations.

To make this process easier and more streamlined, organizations should:

• Choose a SAST tool with built-in compliance frameworks.
• Encourage secure coding standards, like OWASP Top 10, among developers
• Facilitate collaboration between development and application security teams through meetings and workshops.
• Use clear compliance dashboards that visually and easily show any possible violations and the overall posture.

Additional SAST tool features to take into consideration include:

• Audit trails, for documenting of SAST activities
• Integrations with development tools
• Reporting capabilities, which fosters transparency and accountability.

Limitations of Static Application Security Testing Methodology

Albeit the multiple advantages of SAST, when building your security stack it’s important to take the following limitations into consideration:

No Dynamic Code Scanning

SAST is static by nature. It analyzes the codebase without executing it. This means it cannot capture runtime behaviors, environment configurations, or interactions with other systems and services that could introduce vulnerabilities.

These include vulnerabilities that arise from specific deployment configurations, user interactions, or runtime conditions (like memory management issues); APIs that dynamically generate content and handle data; and microservices architectures or cloud services can have complex, dynamic interactions.

Source Code Analysis Depth and Breadth Limitations

While SAST tools analyze source code, different SAST tools may have varying levels of support for different programming languages and frameworks.

They might be highly effective for some technologies while offering limited coverage or insight for others, particularly with the popularity of cross platform application consumption.

In addition, modern programming languages and frameworks often include advanced features and abstractions. SAST tools might not fully understand the implications of these features, potentially missing vulnerabilities that span across multiple components or layers or misinterpreting code patterns.

Be sure to choose a SAST tool that supports all languages and frameworks, as well as both deep and wide scanning, to cover all such use cases.

SAST vs DAST vs IAST vs SCA

You’ve probably heard of SAST mentioned alongside terms like DAST and IAST. Let’s break down the differences and how they compare.

Static vs Dynamic Application Security Testing

SAST analyzes the source code of an application.

It’s performed early in the development lifecycle, and often integrated directly into the development environment.

This allows for early detection, comprehensive coverage and makes it a developer-friendly solution.

However, SAST can produce false positives or negatives since it does not analyze vulnerabilities at runtime.

This is where DAST comes in.

DAST (Dynamic Application Security Testing) is a set of security technologies that analyzes the application from the outside while it’s running. It simulates an attacker’s approach to discover vulnerabilities. DAST is typically performed later in the development lifecycle, once a runnable version of the application is available.

The DAST approach allows identifying vulnerabilities that only become apparent when the application is running, such as issues with user sessions, authentication, and server configurations.

DAST can also test any application accessible via a network, regardless of the language or technology used to build it.

However, relying solely on DAST has its limitations.

Late detection of vulnerabilities makes them more expensive and time-consuming to fix.

In addition, DAST potentially misses vulnerabilities in unexecuted code.

Analyzing the results is also less developer-friendly, because it typically requires more security-specific knowledge to interpret and act on the results.

SAST vs. DAST – Comparison Table

Static vs Interactive Application Security Testing (IAST)

IAST combines aspects of SAST and DAST by analyzing the code as the application runs.

It monitors the application’s behavior and data flow in real-time.

This approach provides insights into how the application behaves during execution, identifying issues that static analysis might miss.

It also produces fewer false positives and negatives compared to SAST, as it observes actual data and control paths used during application execution. As a result, it can be used in both testing and production environments, providing continuous insight into the application’s security posture.

SAST and IAST complement each other.

SAST is ideal for early-stage detection and remediation of vulnerabilities, allowing developers to address security issues before the application is fully built or deployed.

IAST is more dynamic and interactive, providing real-time feedback and a more accurate analysis by observing the application as it runs. It’s particularly useful for complex, interactive applications that require understanding runtime behavior.

SAST vs. IAST – Comparison Table

SAST vs. SCA: How to Combine SAST with SCA

Software Composition Analysis (SCA) is a set of technologies used to identify and manage the risks associated with using open-source and third-party components.

SCA tools evaluate third party components for security vulnerabilities, licensing issues, and outdated versions to ensure the safety and compliance of the software product.

With the right SCA tools, organizations can boost productivity while remaining secure and compliant.

SAST and SCA complement each other to provide a layered defense against a wide range of vulnerabilities, covering both the internal and external code.

While SAST helps write secure code from the start, SCA ensures that open source third-party components don’t introduce new vulnerabilities or violate licenses.

Both SAST and SCA can be integrated early in the development process and into the CI/CD pipeline, providing continuous, automated security feedback.

This integration ensures that security is a seamless part of the development process, ensuring developers get timely feedback and can fix vulnerabilities before deployment.

It’s important to choose the right SCA tool.

Many tools simply focus on known vulnerabilities in third-party components. They do so by checking the manifest file.

However, a comprehensive solution will also check additional aspects, like contributor names.

AppSec vs Developers: 5 Ways to Help Developers Embrace SAST

Traditionally, developers and AppSec teams have worked in silos.

Developers’ priority was to quickly deliver code and features to end-users, while AppSec professionals might delay deployment, but ensure code is secure and the organization is protected.

SAST tools can help bridge this gap, through automation, fostering collaboration and providing guided remediation.

Here’s a detailed look:

1. Potential Adoption Issues

Developers might see security as a discipline that slows down development by introducing additional checks and balances.

Also, understanding and effectively addressing security findings often involves a learning curve.

SAST tools can be used to empower development teams to take ownership of code security.

Similarly security teams can be shown the impact of security findings on the developers’ workflow and KPIs.

This fosters better communication, enables providing better security guidance and encourages adoption of security practices.

2. Sensitivity and False Positives

Certain SAST tools scan everything and are thorough supporting zero vulnerability policies. These to a large number of alerts, many of which might be false positives.

For developers, sifting through false positives to find real issues can be time-consuming and reduce their overall productivity.

This can also lead them to distrust the tool, viewing its findings as more noise than signal.

Choose an enterprise SAST tool that reduces the number of inaccurate findings, while still detecting all risks – like SQL injection, cross-site scripting, buffer overflows, cross-site request forgery, and insecure cryptographic storage.

3. Knowing Where to Prioritize

Without understanding the context and risk of vulnerabilities, developers might prioritize less critical issues over more severe ones.

SAST tools can assess and prioritize vulnerabilities based on potential impact, balancing security with development timelines and business objectives.

Take the following 7 steps for more impactful prioritization:

1. Tune your SAST controls for each unique application to account for differences between them.
2. Onboard each application to your AppSec program.
3. Correlate security findings to identify which ones are actually exploitable.
4. Unify dashboards to streamline the process and for effective triage.
5. Eliminate duplication in vulnerability bug tickets.
6. See the entire picture by focusing on critical applications first.
7. Leverage managed services for help as needed.

4. Integrations

Developers benefit most from static security scanning tools that integrate seamlessly into their IDEs and CI/CD pipelines, since this reduces friction and allows for timely feedback.

Therefore, it’s important to choose a SAST tool that syncs up with the tools, systems, and workflows that developers are already using.

5. Interrupting Workflows

Developers who view SAST tools as disruptive or too time-consuming may resist using them or might bypass checks to speed up their work. To build trust, application security executives should consider these features when choosing a SAST software solution:

• An easy-to-use dashboard that can filter and sort results in multiple ways to reveal patterns and other insights.
• Noise filters and presets that reduce false positives while avoiding false negatives.
• Integrations into the environments developers are already using.
• Built-in AI-powered remediation guidance. For example, showing developers the exact piece of referenced code.
• Incremental scanning that analyzes only modified or new code lines.
• Consistent and reliable support.

SAST Scan Characteristics

Here’s what you need to know about SAST scanning:

Open Box Testing Methodology

SAST is often described as an “open box” or “white-box” testing methodology. Unlike its counterpart, DAST, which tests an application from the outside in, SAST delves into the application’s internal structure, code, and design. This approach provides a comprehensive understanding of how data flows through the application, enabling it to identify complex issues like input validation problems, race conditions, and more.

2. Main Types of SAST Scans

There are three main types of SAST scans:

• Source Code Analysis – The original application source code.
• Bytecode Analysis – The intermediate code.
• Binary Code Analysis – The final compiled code of the application.

3. Scan Speed

The speed of a SAST scan can vary significantly based on various factors. First, the size and complexity of the codebase. Larger and more complex applications take longer to scan. Second, the type of scan being performed: Some scans, like pattern-based scans, are quicker, while flow-based scans might take more time due to their depth of analysis. Finally, the tool’s capabilities and configuration: Different tools and configurations can lead to variations in scan speed.

To increase the speed, accuracy, and efficiency of the scans, you can restrict the scan coverage to specific programming languages or categories of languages.

In addition, certain SAST tools support incremental scans. This means they don’t require a complete build to launch a scan, which saves significant time.

4. What Kind of Vulnerabilities Can SAST Tools Detect?

Static security scanning tools can detect risks like injection flaws and SQL injections, cross-site scripting (XSS), buffer overflows, cross-site request forgery (CSRF), improper authentication and access controls and insecure cryptographic storage.

5. What Level of Sensitivity (False Positives) Do You Want?

The level of sensitivity in a SAST tool refers to its threshold for reporting vulnerabilities. Higher sensitivity means it will report more potential issues, but also increases the likelihood of false positives (benign code flagged as vulnerable). High sensitivity might be preferred in early development stages to ensure no potential issue is missed or in highly-regulated industries. Lower sensitivity might be more suitable closer to deployment to focus on the most critical and certain vulnerabilities, reducing the noise for developers.

Choose a SAST tool that can scan both deep and wide:

• Deep – The most thorough scan to uncover all high, medium, and low-severity vulnerabilities for a comprehensive overview.
• Wide – A high-level scan for finding the most critical high-severity vulnerabilities and gaining a high-level view of risk.

Enterprise SAST Tool Tech Considerations

Choosing the right SAST tools for your needs requires mapping your use cases and breaking them down into technological requirements. When doing so, take the following into consideration:

1. Supported Languages

Organizations choose languages and frameworks based on personal preference, task requirements, application needs, developer goals and organizational standards.

Therefore, SAST solutions should support a wide scope of languages and frameworks.

Choose a vendor that supports the largest number of languages and frameworks and frequently adds new languages so you can standardize on a single application and future-proof your application security platform.

2. IDE and Tech Integrations

Integrating and automating SAST solutions into the SDLC will increase development adoption. The alternative, interruptions and adding additional steps, will create frustration and delay secure deployment.

Common integrations in SAST solutions should include:

• SCM solutions – Bitbucket, GitHub, GitLab, etc.
• IDE solutions – Eclipse, IntelliJ, Visual Studio, etc.
• CI/CD solutions – Jenkins, CircleCI, Bamboo, TeamCity, etc.
• Feedback solutions  – Azure DevOps, Jira, Rally, etc.

Choose a vendor that supports these integrations as well as custom integrations.

3. Scan Speeds/Presets/Best Fix Location

Scan Speeds

Waiting for code to compile before scanning can be annoying, and many developers will skip scans or ignore results.

Therefore, SAST solutions should incrementally scan after major changes and  scan at the source code repository level, avoiding the need to rebuild code.

Choose a vendor that can scan uncompiled code and directly from repositories.

Presets

AppSec teams can use presets, which are out-of-the-box groups of rules, to support use cases and compliance needs.

SAST solutions should offer multiple presets to help AppSec teams.

Choose a vendor that supports modifying queries and creating custom queries.

Best Fix Location

When detecting vulnerabilities, there are SAST solutions that rely on regex and pattern-matching. These approaches lack context.

SAST solutions should provide deeper analysis.

Choose a SAST vendor that provides a best fix location and guides developers to where coding errors exist and how to remediate them.

“Enterprise vs. Good Enough” Making the Right Choice

On top of available features and capabilities, some SAST tools were built for the enterprise, while others were built for a wide variety of organizations, and may not be sufficient to answer enterprise needs.

How can you distinguish between enterprise SAST solutions and SAST tools that are merely “good enough”?

Consider the following:

Languages

• Enterprise-level SAST tools typically offer broad language and framework support, understanding that large organizations often use a diverse stack of technologies. They are regularly updated to include the latest language versions and frameworks, ensuring that even the most modern or niche languages are covered. This comprehensive language support ensures consistent security practices across all projects and teams, security standardization and future-proofing the stack.
• Good Enough / Non-Enterprise tools might support popular or common languages but often lack the breadth or depth of their enterprise counterparts. They might not be as quick to update for new language versions or frameworks, potentially leaving newer codebases less protected. While sufficient for smaller teams or projects with a more uniform tech stack, such solutions might struggle in a diverse, fast-evolving environment.

False Negatives

• Enterprise SAST solutions typically invest heavily in reducing false negatives (real vulnerabilities that are not reported). They incorporate advanced deep SAST analysis techniques and are regularly updated with the latest security research to ensure they can detect emerging threats. The goal is to provide a safety net as robust as possible, understanding that in large organizations, even a single overlooked vulnerability can have significant repercussions.
• Good Enough / Non-Enterprise tools might not have the same level of sophistication or resources dedicated to minimizing false negatives. They might rely on more general or outdated vulnerability databases and lack the advanced analysis capabilities of enterprise tools. This doesn’t mean they’re insecure, but there might be a higher risk of not catching every potential issue.

Speed vs. Quality

• Enterprise SAST tools often provide a balance between speed and thoroughness. They are designed to integrate seamlessly into the CI/CD pipeline, providing quick feedback to developers without significantly slowing down development processes. However, they also offer deep, comprehensive scans to ensure quality. Such tools also provide customizable settings to balance speed and depth based on the project’s needs.
• Good Enough / Non-Enterprise tools might prioritize speed to appeal to smaller teams looking to integrate security without a resource drain. They can provide quick scans and feedback, which is excellent for early and frequent testing. However, the trade-off might come in the form of less thorough analysis, potentially missing complex or less common vulnerabilities.

Benefits of SAST on Checkmarx One

Checkmarx SAST engine is an integral part of the Checkmarx One application security testing platform – the industry leading cloud-native platform that builds DevSecTrust.

The platform secures every phase of development for every application from the very first line of code until production while simultaneously balancing the dynamic needs of security and development teams.

The main benefits enjoyed by more than 1,800 customers, including 60% of Fortune 100 Organizations, include:

The Platform

SAST on Checkmarx One was built for developers, providing best fix location of where to fix the vulnerability and the vulnerable line of code, as well as guided remediation advice, straight in the IDE. Guidance includes security context, explaining the attack vector and the point to place in the code. Checkmarx One enhances #DevSecTrust by enabiling them to prioritize for the greatest business impact, meet developers where they live, and equip developers with the tools and knowledge to deliver secure applications.

Through automation and integrations, SAST on Checkmarx One becomes a part of the SDLC, integrating with IDEs as well as build management servers, bug tracking tools and source repositories. This aligns security testing with quality testing.

In addition, SAST scans run on the server instead of on the developers’ workstation, so developers can continue working without interruption. These capabilities save time for developers, empowering them and increasing adoption.

SAST on Checkmarx One supports all major languages, including over 50 languages and 80 language frameworks, coverage for the latest development technologies and zero configuration to scan any language. Incremental scanning capabilities ensure only new or modified code is scanned, reducing scanning time by 80% and allowing for scalability.

For AppSec teams, the platform is agile and flexible, allowing to adapt the rule set to proprietary code and minimizing false positives, expanding rules per compliance requirements, and providing a detailed explanation of the root cause of every result.

Risk Management

Conclusion

The path to selecting and integrating the ideal SAST tool into your organization’s SDLC requires delicate consideration on the part of CISOs, AppSec professionals, and DevOps teams. The right tool can significantly enhance the security posture and efficiency of development processes. As we’ve explored, SAST is not just about finding vulnerability, it’s about fostering a culture of security-minded development, ensuring compliance, and enhancing overall software quality.

When making your final choice, consider how the SAST tool aligns with your organization’s specific needs, technology stack, and development culture. The goal is to select a tool that not only scans for vulnerabilities but also integrates seamlessly into your workflows, offers clear and actionable insights, and supports your developers in writing secure code from the outset. Remember, the best SAST tool is one that your team will actively use and trust, creating a proactive security stance.

Be guided by the principles of early integration, continuous feedback, and collaborative security, ensuring that every line of code contributes to the strength and integrity of your digital assets. With the right approach and tools, your journey toward secure coding practices can become a cornerstone of your organization’s success and resilience in the face of cybersecurity challenges.

Related Resources

• https://checkmarx.com/cxsast-source-code-scanning/
• https://checkmarx.com/resources/ebooks/sast-10-key-consideration-2023/
• https://checkmarx.com/learn/sast/simple-strategies-to-help-developers-embrace-sast/
• https://checkmarx.com/learn/sca/sca-sast-dast/
• https://info.checkmarx.com/trust-paradigm/
• https://docs.checkmarx.com/en/34965-46508-configuring-cxsast-scan-flow-processes.html