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SAST vs DAST: Uncovering the Variances in Application Security Testing
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Quick Summary: SAST and DAST are two prominent methods for application security testing. SAST involves testing applications using the source code and DAST tests applications using simulated attacks. This article provides a comparison between SAST and DAST. Keep reading to understand their meanings and differences.
Every day, organizations have to face a relentless battle against malicious threats targeting their sensitive data and software applications. This has spurred the adoption of comprehensive security testing methodologies, with Static Application Security Testing (SAST) and Dynamic Application Security Testing (DAST) emerging as prominent players in the arsenal of defense.
If we look at the statistics, as per the report, the worldwide number of malware attacks reached 6.06 billion, an increase of two percent compared to the preceding year. Therefore, to mitigate risks and vulnerabilities, understanding the similarities and differences between these methodologies is essential for you to craft a robust and resilient security strategy.
In this detailed article on the difference between SAST and DAST, we will analyze both methods and explore their strengths and weaknesses in fortifying the security posture of software applications. By unraveling the intricacies of these security testing methodologies, you can make informed decisions to enhance overall security resilience.
Table of Contents
- What is SAST?
- Why is SAST Important?
- What is DAST?
- Why is DAST Important?
- Market Overview of SAST and DAST
- Key Difference Between SAST and DAST
- SAST vs DAST: Differences
- Similarities: DAST and SAST
- ZeroThreat: An Advanced, Next-Gen DAST Tool
What is SAST (Static Application Security Testing)?
SAST or Static Application Security Testing is one type of security testing that scans the application’s source code in a static or non-running state. Since this security testing method provides a comprehensive view of app’s source code, it is also known as “White Box” testing. Also, it identifies potential vulnerabilities by thoroughly examining them.
SAST is performed at an early stage of the software development life cycle (SDLC) – before the execution of the code. The primary objective of SAST tools is to identify vulnerabilities and weaknesses in the software code that may result in security breaches. In fact, the SAST methodology can help you identify vulnerabilities like buffer overflows, input validation flaws, insecure server configurations, XML external entity (XXE) attacks, and other OWASP Top 10 security risks by scanning the code while it’s not executing.
While plenty of SAST tools are available in the market to identify potential security threats, it’s not without its challenges. Since SAST is static, it cannot detect vulnerabilities that occur during runtime, and it may sometimes have false positives. However, SAST can be an effective security strategy when utilized correctly and in conjunction with other testing methods.
Why is SAST Important?
SAST is a unique method to identify security vulnerabilities before the code is executed. However, it offers many benefits; the significant importance of SAST is identifying vulnerabilities and marking their precise location, including the file name and line number. In fact, the SAST tool defines the severity of each detected issue and offers a brief description. This makes the SAST methodology cheaper and easier to fix vulnerabilities in software applications.
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What is DAST (Dynamic Application Security Testing)?
DAST or Dynamic Application Security Testing is a “Black Box” testing methodology used to identify security vulnerabilities that malicious attackers could exploit in running web applications.
DAST uses the exact opposite of the SAST approach. Unlike SAST, DAST tools don’t scan the application’s source code. So, the dynamic application security testing methodology is executed later in the development cycle – before deploying the application code.
Dynamic Application Security Testing (DAST) primarily aims to identify vulnerabilities that may not be evident in the source code but can become exploitable once the application is executed. This includes multiple vulnerabilities like SQL injection, cross-site scripting (XSS), or vulnerability sources like OWASP Top 10 or SANS/CWE 25.
Although DAST tools offer a valuable viewpoint on possible runtime vulnerabilities, they are not without challenges. When it comes to business logic vulnerabilities, for instance, DAST may miss vulnerabilities that are not exploitable in the running state and may result in false negatives. However, advanced DAST tools and solutions address many of these drawbacks.
In a nutshell, the primary difference between DAST and SAST is that SAST utilizes a white-box testing technique, whereas DAST uses a black-box testing technique.
Another major difference between SAST vs DAST is that DAST can only be used much later in the development process than SAST since it requires functional software applications.
Why is DAST Important?
When compared to other standard testing methods that focus on the code and technology within your application, DAST helps you identify security risks and vulnerabilities in your apps that are unlikely to be discovered.
DAST uses attack simulations to find security weaknesses in the application, allowing software developers to fix them before the real attackers exploit them.
DAST tools like ZeroThreat are capable of identifying OWASP Top 10 and CWE Top 25 vulnerabilities. DAST can be used to test your application's exterior environment as well as dynamically verify the internal state of your application based on inputs and outputs.
Market Overview of SAST and DAST
According to the survey by Mordor Intelligence, the Dynamic Application Security Testing market is projected to be valued at USD 7.17 billion by 2029, achieving a compound annual growth rate (CAGR) of 18.74% over the forecast period from 2024 to 2029.
As per a MarketsandMarkets report, the size of the global security testing market is projected to reach USD 43.9 billion by 2029, with a compound annual growth rate (CAGR) of 24.7%.
Key Difference Between SAST and DAST
When it comes to implementation, many organizations often refer to the advantages and disadvantages of SAST vs DAST. We have seen in the above section that these two are different approaches to finding vulnerabilities within the software development life cycle with their own benefits.
Now is the time we should go further to understand the difference between DAST and SAST.
Implementation
While talking about SAST vs DAST, SAST is generally executed at an early stage of SDLC – before the compilation and execution of the code to find vulnerabilities. This early detection approach helps you fix issues and prevent potential vulnerabilities immediately, resulting in saving time, costs, and resources.
On the other hand, DAST is executed after executing the application. It scans the entire application in its operating environment, simulating real-world attacks by cybercriminals to identify threats and vulnerabilities.
Furthermore, integrating modern DAST tools into SDLC allows pentesters to execute DAST during the testing stage before the application is in production.
Testing Behavior
SAST examines the binary code or source code of the application. It performs the internal analysis of the application, finding common coding errors and security flaws. The proactive approach of the SAST strategy is designed to prevent security threats before they become attacks.
On the other hand, DAST scans the application from the outside. It engages with the application through its publicly accessible interface, considering it a black box without any knowledge of its internal workings. DAST helps you identify vulnerabilities that may not arise during development but could be exploited when the application is being developed.
Detection of Vulnerabilities
Implementing SAST allows you to identify vulnerabilities like buffer overflows, SQL injections, cross-site scripting (XSS), and others at the code level. In addition, it also detects insecure coding practices that could lead to security vulnerabilities.
While talking about DAST, it can also help you identify runtime vulnerabilities like server configuration errors, application-level denial of service (DoS) attacks, and other vulnerabilities like SQL injections, XSS, and OWASP Top 10 that arise from the application’s interaction with its environment. It’s helpful in identifying vulnerabilities that SAST would miss and are not code related.
Ability for False Positives and Negatives
When we talk about false positives and negatives, no tool – SAST and DAST are perfect. Since SAST examines the source code in detail, it frequently finds false positives when the tool incorrectly detects a vulnerability. Sometimes, it may misinterpret safe code as vulnerable, resulting in unnecessary remediation efforts.
In contrast, DAST is more likely to produce false negative results. As a result, it may fail to detect a real vulnerability. Its black-box approach may miss security flaws that are concealed deep within the application’s code or that are only visible in particular circumstances.
Since DAST evaluates the application while running, it gives you a more precise and realistic picture of potential vulnerabilities. Furthermore, next-generation DAST solutions from ZeroThreat use generative AI technology to eliminate false positives and negatives to virtually zero.
Language Dependency
Since SAST is used during the SDLC and scans the entire source code, it’s highly reliable on the programming languages and frameworks used to develop an application. The SAST tool you use must support programming languages like – C++, Python, Go, React, Ruby, and many more.
DAST is a language or framework independent. It means unlike SAST, DAST is not concerned with the languages or frameworks used to build an application for testing. It scans your application from the outside like an attacker would.
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SAST vs DAST: Differences
Since static application security testing (SAST) and dynamic application security testing (DAST) tools are used to identify security vulnerabilities, organizations find them useful differently at SDLC.
Below is the table, which represents the key differences between DAST vs SAST.
Aspect | SAST | DAST |
---|---|---|
Testing Type | White box security testing | Black box security testing |
What it Tests | Source code (or intermediate or binary code) | Running application |
When it Tests | Early in SDLC, as code is written | Later in development and in production |
Testing Approach | Like a developer | Like a real-life hacker |
Vulnerability Coverage | Coding errors and misconfigurations | Runtime vulnerabilities |
Detectable Vulnerabilities | Security issues evident in source code | The majority of security flaws, such as runtime problems and configuration errors that attackers might target |
Location of Vulnerabilities | Finds the exact location | Finds vulnerabilities without pointing to a particular line of code |
Run-time Issues | A SAST tool can only check static code; run-time vulnerabilities are beyond its scope | An application can undergo dynamic analysis with a DAST tool, which can also identify run-time problems |
Scope | SAST can be applied to software like web applications, web services and mobile applications | Typically, DAST tools are platform specific |
Key Benefit | It identifies problems with the source code. Also, it reduces the number of vulnerabilities introduced during coding | Tests the functionality of an application, including server configurations, third-party components, and APIs, regardless of the programming language or the source code's accessibility |
Limitation | Dependent on programming languages or frameworks. Requires fine-tuning to minimize false arms | Unable to pinpoint the exact location of a vulnerability in the source code. Requires a runnable app for testing |
Similarities: DAST and SAST
As we have seen, SAST and DAST offer unique features and advantages to organizations, along with some differences. After all, SAST and DAST tools are two sides of the same coin in security testing, which means you will find some similarities as well.
Let’s understand in what terms these methodologies are similar.
- Both DAST and SAST tools are used to identify vulnerabilities in the applications.
- SAST and DAST tools are integrated into the software development life cycle to provide developers with continuous testing and immediate feedback.
- Both security testing methodologies include automation capabilities that can expedite testing and reduce the required manual effort.
- Both security testing tools generate reports that include a list of the vulnerabilities found and suggestions for fixing them.
- Both tools are essential components of a comprehensive application security program. Combining SAST and DAST tools can help organizations address various security testing needs.
- SAST and DAST tools are capable of identifying vulnerabilities and security risks, like data breaches, application downtime, and financial losses.
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ZeroThreat: An Advanced, Next-Gen DAST Tool
ZeroThreat is a next-gen DAST tool that scans and tests the application in every aspect. ZeroThreat is capable of scanning any target elements, including web applications, internal applications, and APIs (REST, GraphQL, SOAP). The major benefit of using ZeroThreat is it seamlessly integrates with any framework, tool, or language you already use. It performs a blazing-fast scanning process, delivering accurate and comprehensive vulnerability reports to fix them.
In addition, ZeroThreat leverages Generative AI, which communicates with applications and APIs intelligently instead of just crawling applications and doing the guesswork. In fact, our AI-driven engine understands application architecture and generates simulated attacks that real attackers would do. ZeroThreat ensures false positives reports are shared by verifying and exploiting the vulnerabilities.
Capabilities of ZeroThreat
- Seamless Integration with Any Environment: ZeroThreat can be easily integrated into your existing CI/CD pipelines. It also performs trigger scans on every commit or pull request.
- Setup, Configure, and Scan: ZeroThreat works in three simple steps. Also, you don’t have to do any UI-based configuration in your system.
- Blazing Fast Scan: Instead of scanning and crawling applications and APIs, its AI-powered engine interacts with applications and ensures to scan faster. Also, ZeroThreat understands the application architecture and workflows to generate targeted attacks for accuracy.
- No False Positives: Developers and testers may focus on releasing code by using AI analysis to prevent returning false positives.
ZeroThreat can help you get the most out of DAST — and much more — to help you improve the security of your applications without sacrificing speed.
Frequently Asked Questions
What are the differences between SAST and DAST?
SAST is static code analysis in which the source code of an application is examined to identify vulnerabilities. It is the Whitebox testing method. DAST involves evaluating applications based on simulated attacks and is the Blackbox testing method.