Security threats and data breaches have become more common and may have huge financial and business implications for your organization. As such, you must be able to detect vulnerabilities in your applications fast.
There are several ways to find security vulnerabilities, and we’ll cover two application security testing methods in detail:
- What is SAST – Static Application Security Testing?
- What is DAST – Dynamic Application Security Testing?
- SAST vs. DAST: what’s the difference?
In this article, we are focusing on Static Application Security Testing (SAST). Keep reading to know what SAST is, why it is important, and its pros and cons.
What is SAST?
Static application security testing (SAST) is a white-box testing method that examines the source code to find software vulnerabilities, flaws, and weaknesses. These vulnerabilities include SQL injection attacks, cross-site scripting, buffer overflows, and others listed in the OWASP Top 10 security risks.
Your team should perform SAST early and often in the development lifecycle against the entire codebase. SAST tools scan the application from the inside out to identify vulnerabilities in the code before compilation or execution. Finding these vulnerabilities earlier in the development lifecycle makes the life of your developers easier to ship high-quality code and enhances the overall application security.
Why is SAST important?
SAST tools automatically identify critical vulnerabilities earlier in the software development lifecycle, enabling you to shift security left. By doing so, SAST tools also decrease the cost of fixing the issues and their potential impact. For example, if you didn’t find vulnerabilities before you deploy the application, it could lead to a severe data breach, resulting in financial loss and damage to your organization.
SAST tools analyze your entire codebase, and they are much faster than manual code reviews performed by humans, scanning thousands of lines of code in a matter of minutes. As a result, integrating SAST into your software development lifecycle can significantly improve the overall quality of your code.
Some SAST tools point out the vulnerabilities’ location and highlight problematic code, guiding you on how to fix the issues. As such, developers have real-time feedback on the quality of their code, which helps them learn from previous mistakes and develop more secure code in the future.
SAST can also help you in the process of being compliant with standards or getting certifications, like ISO/IEC 27001:2013 or PCI DSS.
SAST pros & cons
SAST tools are great for analyzing source code. However, they cannot identify vulnerabilities happening during runtime. As in every method, SAST has its pros and cons. Let’s take a close look at them.
Pros of SAST
- Does not require source code execution: SAST works on the source code before the application runs. As such, SAST scans can be incredibly fast.
- Fixing vulnerabilities is cheaper: Since SAST doesn’t need a deployed application, it can be performed earlier in the development lifecycle, reducing the cost and time required to fix the identified vulnerabilities.
- Shows problematic code locations: SAST can point you to the exact location of a vulnerability, allowing you to fix the issues immediately. As a result, you and your team don’t spend days digging through source code, and you cut down on development time.
- Does not require test cases: SAST tools will apply their entire rule set to your codebase. By doing so, it allows you to catch vulnerabilities you might otherwise miss.
- Easy automation and fast scanning: SAST does not need many configurations, making the automation simple and easy.
- Faster at scanning than humans. SAST analyzes your entire codebase faster than humans. In fact, some tools can scan thousands of code lines in just a few minutes. So when you integrate a SAST tool into your development lifecycle, your team can focus on coding instead of security checking.
- Detection of common vulnerabilities: SAST tools can identify code patterns associated with common vulnerabilities, such as OWASP Top 10 security risks.
- Compatible with several programming languages. SAST tools are available for most mainstream languages and frameworks. As such, you shouldn’t have trouble finding an appropriate SAST tool for your team’s needs.
Cons of SAST
- High risk of reporting false positives: SAST works on source code, so it often doesn’t consider the entire picture. Some issues are false positives, meaning they may not be a problem. As such, developers much analyze the SAST tool results to determine whether they represent real security risks, which can slow down development.
- Programming language dependency: SAST analyzes your source code, meaning it is language-specific. For most mainstream programming languages (e.g., Java and C), there are a lot of SAST tools available, but for niche languages (e.g., ReScript and Clojure), there are very few SAST tools.
- Reports become outdated quickly: Since SAST tools only generate static reports, those reports become obsolete quickly. As such, you must run a SAST scan multiple times during the development lifecycle to catch new code errors or security vulnerabilities.
- No analysis of running vulnerabilities: SAST tools cannot identify vulnerabilities in dynamic environments, making them ineffective in finding configuration errors and runtime issues.
- Difficult initial setup: The initial setup of SAST, if you already have a large codebase, does not come easy. SAST tools usually detect many issues when the tools check source code for the first time. So you need to choose a tool that will give you fewer challenges when setting it up.
- Need to get more than one SAST tool: Sometimes, it is advisable to have more than one SAST tool as one may not detect all the vulnerabilities in an application.