All Static Application Security Testing (SAST) tools perform the same basic ability: Scanning source code to detect security risks. However, the features and capabilities that SAST tools provide vary widely in ways that impact the efficiency and effectiveness of the solutions.
That’s why it’s important to assess the differences in how SAST tools work when evaluating different offerings. To provide guidance, this article breaks down the key features and capabilities you should expect from a modern SAST tool.
What are SAST tools?
SAST tools are a type of security scanner that analyzes static code to identify security risks. SAST tools work by parsing application source code and/or binaries and looking for signatures of common security flaws – such as code that is susceptible to injection attacks.
SAST tools are distinct from certain other types of security scanners – such as Dynamic Application Security Testing (DAST) tools, which evaluate running applications for security flaws – because SAST focuses on scanning static, non-running applications. In addition, SAST is distinct from Software Composition Analysis (SCA) tools, which scan applications for security vulnerabilities and licensing issues linked to third-party open source components – a different category of risk from the type that most SAST software detects.
What makes a good SAST tool?
While the ability to detect security risks is the key capability that any SAST tool must deliver to be worthy of its name, scanning is just one of the many considerations that impact how useful a SAST tool is.
Another important factor is how well the SAST tool integrates into the software development lifecycle (SDLC). To avoid delaying application releases, SAST tools should be able to connect seamlessly to the tools that developers use to write and stage applications, then perform tests in a way that keeps pace with the other processes that occur during the SDLC.
Scan speed is important, too. The time it takes a SAST tool to complete a scan can vary widely depending not just on the volume and complexity of the code it’s testing, but also on the efficiency of the tool itself. If your SAST tool lacks fast scanning capabilities, it may end up delaying your software development operations because you have to wait for time-consuming security tests to finish before you can deploy a new application release.
Last but not least, the type of developer experience that a SAST tool delivers is critical. Solutions that delay software development operations can frustrate developers – and lead to friction between development and AppSec teams – by reducing the rate at which they can build and release new features.
Likewise, if your SAST tools generate a large volume of alerts with a low accuracy rate, developers may waste time responding to issues that are not actually relevant. At the same time, a tool that doesn’t show alerts but rather lets vulnerabilities be found later by other tools or – even worse – released into production is also problematic.
For reasons like these, it’s important to look for SAST tools that help development teams work faster, accurately, and more efficiently, as opposed to becoming a burden that detracts overall from their job satisfaction.
Capabilities and features to expect from the best SAST tools
Now that you know what SAST tools do and how they impact the SDLC and developer experience, let’s talk about specific features and capabilities that highly effective SAST tools provide.
#1. Broad language and framework coverage
To identify security flaws in an application written in a given programming language or framework, a SAST tool must be able to interpret code in that language or framework. Some SAST tools support more languages and frameworks than others.
The best solutions work with a broad range of languages and frameworks. This is important because these tools are better equipped to detect security risks no matter which types of applications your developers are building and allow organizations to consolidate on a single set of tools rather than using one tool for Java and another for Python. In addition, SAST tools that offer broad coverage make it easy for your teams to adopt a new language or switch to a new framework whenever they wish – as opposed to being bound to a limited range of languages or frameworks due to a lack of SAST compatibility with alternatives.
#2. Incremental scanning
Incremental scanning is a feature available in some SAST tools that makes it possible to run tests without waiting for an entire application build to complete. Instead, the scans are incremental, meaning that some parts of an application can be scanned before others.
Incremental scanning is a key capability because compiling code is often a time-consuming task. Thus, if scanning could not begin until all code is compiled and code that wasn’t changed needs to be scanned again, teams would risk major delays to meeting crucial business deadlines. Incremental scanning makes it possible to scan in a more efficient way that keeps security testing at pace with software development.
#3. Highly accurate scanning
Discovering security flaws in your application is bad enough. What’s even worse is receiving false-positive alerts about a problem that turns out not to be an issue. And even worse [f][g]than that are false negatives, which happen when a scanner misses a legitimate security problem.
To avoid these issues, SAST tools should be able to deliver highly accurate scan results and minimize false negatives and positives. Accuracy is partly determined by how well-designed a SAST tool is, but it’s also affected by features like the ability to customize test rules and queries. These capabilities allow teams to tailor scanning based on the unique attributes of specific applications, leading to more accurate results.
In addition, testing based on data-flow analysis and symbolic execution enhance scan accuracy because this approach evaluates how an application actually behaves. Alternative scanning methods, such as rudimentary regex matching, deliver less accurate results because they don’t consider how an application actually processes input – they just look for simple code patterns associated with known security issues. “Good enough” isn’t really good enough.
#4. Preset support
Presets (also known as rulesets) are built-in rules that teams can use to guide scanning without having to develop their own policies from scratch. For organizations that need to meet specific compliance mandates or align with industry-recognized best practices, presets save a lot of time by enabling out-of-the-box scans that align with frameworks or recommendations like HIPAA and OWASP Top Ten.
The ability to customize scanning based on unique application characteristics is important, too, of course. But presets help teams address basic testing needs, giving them more time to set up additional custom rules to round out their SAST testing routine.
#5. Remediation guidance
Minimizing the time it takes to fix security issues and avoid delays to the SDLC requires not just fast and accurate scanning, but also guidance to help developers remediate flaws as efficiently as possible. SAST tools that provide this guidance deliver the best Mean Time to Remediate (MTTR) rates.
On top of that, remediation guidance also enhances the developer experience. Instead of having to figure out how to fix problems from scratch, or turning to the Internet for guidance, developers get assistance directly from the same SAST tools that generated security alerts. Some tools, such as Checkmarx, even can use the power of AI to automatically provide code snippets to fix the vulnerabilities.
How Checkmarx SAST stands out
As a Static Application Security Testing solution designed from the start with accuracy, speed, and developer experience in mind, Checkmarx SAST provides all of the critical capabilities that organizations should expect from a best-in-class SAST tool. With features like data-flow analysis and symbolic execution, an AI-powered query builder that makes it fast and easy to write custom test queries, and a broad preset library, Checkmarx SAST helps development and AppSec teams find and fix security flaws as efficiently as possible.
To learn more about how Checkmarx can help meet your SAST testing needs, you’re welcome to request a demo.