Static Application Security Testing (SAST)

Software security is an essential aspect of software development, and Static Application Security Testing (SAST) is an essential tool in ensuring software security. SAST is a type of security testing that involves analyzing source code or compiled binaries to identify security vulnerabilities. SAST tools can help developers find security flaws early in the development life cycle, reducing the risk of security incidents and ensuring compliance with security standards. This chapter will provide an overview of SAST security, as well as its benefits and limitations, and discuss how it fits into the overall software development process.

SAST occurs early in the Software Development Life Cycle (SDLC) as it analyzes code in a non-running state and does not require a working application. This chapter covers the free and open source tools around SAST:

• What is SAST?
• Identifying vulnerabilities early in the development process
• Resolving...

Introduction

Software security testing is a crucial component of the software development process as it ensures that software applications are secure and resilient against attacks. It involves testing software for vulnerabilities and weaknesses that attackers can exploit to gain unauthorized access, steal data, or cause harm to the system. Various types of security testing exist, including SAST, Dynamic Application Security Testing (DAST), Interactive Application Security Testing (IAST), and penetration testing.

Security testing is not a one-time activity but rather a continuous process that needs to be integrated into the SDLC. It involves identifying security requirements, assessing potential risks, developing security controls, implementing security measures, and monitoring the system for any security incidents.

Software security is a critical aspect of modern software development, and it requires continuous attention and effort to ensure that software applications are secure...

What is SAST?

SAST is a type of security testing that analyzes source code or compiled binaries to identify potential security vulnerabilities. SAST is performed during software development and helps developers find security flaws early in the SDLC.

SAST is beneficial in identifying security flaws early in the development process, facilitating easier and more cost-effective remediation. Additionally, SAST helps ensure compliance with security standards and regulations, such as the OWASP Top Ten, PCI DSS, and HIPAA.

However, SAST has its limitations. Many SAST tools produce false positives and false negatives, which can be time-consuming to investigate and fix. False positives occur when the tool identifies a vulnerability that is not present, while false negatives occur when the tool fails to detect an actual vulnerability. SAST tools can also have difficulty detecting certain types of vulnerabilities, such as those related to runtime behavior. A false negative is a term that...

Identifying vulnerabilities early in the development process

Identifying vulnerabilities early in the development process is one of the key benefits of SAST, along with Software Component Analysis (SCA) and threat modeling. SAST tools analyze application source code before it is compiled and deployed, allowing vulnerabilities to be identified early in the development cycle. By doing this, organizations can remediate them before they are deployed into production. This reduces the risk of security incidents and minimizes the cost of remediation.

Identifying such vulnerabilities early is a key benefit of SAST as it allows organizations to remediate vulnerabilities before they are deployed into production, reduce the risk of security incidents, and comply with regulatory requirements.

The SAST process

The SAST process is a set of activities and workflows that are used to perform SAST. Here is an overview of the typical SAST process and workflow:

1. Tool selection: The first...

Resolving issues without breaking the build

Resolving issues without breaking the build is an important aspect of integrating SAST into the development process. We need to make sure that when we help developers identify any critical issue in the build with the DevSecOps process, the build is not failing and we can still fix the issues within the stipulated timeline. To accomplish this, developers need to understand the nature of the vulnerability and its impact on the application. They also need to have access to tools and resources that can help them resolve the issue, such as code snippets or guidance on best practices.

One approach to resolving issues without breaking the build is to use an iterative development process. In this approach, developers identify and remediate vulnerabilities in small batches, testing each change to ensure that it does not introduce new vulnerabilities or break the build.

Another approach is to use code branching and version control to isolate...

The benefits of SAST

SAST provides several benefits for organizations looking to improve the security of their software applications. Here are some of the key benefits of SAST:

• Early identification of security vulnerabilities: SAST tools analyze application source code before it is compiled and deployed, allowing vulnerabilities to be identified early in the development cycle. This enables organizations to remediate vulnerabilities before they are deployed into production, reducing the risk of security incidents and minimizing the cost of remediation.
• Integration into the development process: SAST tools can be integrated into the SDLC, providing feedback to developers during the coding process. This allows developers to address vulnerabilities as they are introduced, reducing the need for post-release remediation.
• Comprehensive analysis: SAST tools can perform a comprehensive analysis of the application source code, identifying potential vulnerabilities that may not...

The limitations of SAST

While SAST can identify vulnerabilities early in the software development process, it can produce false positives and false negatives, has a limited scope, and is less effective against certain types of vulnerabilities. SAST should be used in combination with other security testing techniques to ensure that software applications are secure and resilient against security risks.

Here are some of the key limitations of SAST:

• False positives: SAST tools can produce false positives, which are security vulnerabilities that are reported by the tool but do not exist in the code. False positives can be time-consuming to remediate as they require additional analysis and can take resources away from more critical vulnerabilities.
• False negatives: SAST tools may miss actual vulnerabilities, leading to a false sense of security.
• Limited context: SAST tools analyze application source code in isolation, without considering how the code interacts with other...

Open source SAST tools

Several open source SAST tools are available that organizations can use to identify security vulnerabilities in their code. Here are some of the most popular ones:

• Bandit: Bandit is a SAST tool explicitly designed for Python applications. It identifies common security issues such as SQL injection, XSS, and buffer overflows. Bandit can be integrated with popular development environments such as PyCharm and Visual Studio Code, and it provides detailed reports that highlight vulnerabilities and recommended remediation steps. It is available for free on GitHub.

  Link: https://github.com/PyCQA/bandit

• FindSecBugs: FindSecBugs is a SAST tool that identifies security vulnerabilities in Java applications. It can identify vulnerabilities such as SQL injection, command injection, and XSS. FindSecBugs can be used with popular Java development environments such as Eclipse and IntelliJ IDEA, and it provides detailed reports that highlight vulnerabilities and recommended...

Case study 1

A software development company was in the process of building a new web application for a client. As part of their development process, they were using a combination of manual code reviews and automated testing tools, including SAST. They had integrated SAST into their development pipeline and were running it regularly to identify any potential security vulnerabilities in their code.

During one of their SAST scans, they discovered a critical vulnerability in their application code. The vulnerability was a classic SQL injection flaw that could allow an attacker to execute arbitrary SQL commands on the underlying database. If left unaddressed, this vulnerability could have potentially exposed sensitive customer data and allowed attackers to take control of the application.

Thanks to the early detection provided by SAST, the development team was able to quickly remediate the issue before deploying the application to production. They fixed the vulnerability by implementing...

Case study 2

A large financial institution was in the process of building a new online banking application. The application was designed to give customers a convenient and secure way to manage their accounts and conduct online transactions. As part of their development process, they integrated SAST into their development pipeline to identify any potential security vulnerabilities in their code.

During one of their SAST scans, they discovered a critical vulnerability in their application code. The vulnerability was a remote code execution flaw that could allow an attacker to execute arbitrary code on the server hosting the application. If left unaddressed, this vulnerability potentially exposed sensitive customer data and allowed attackers to take control of the application and the underlying infrastructure.

Thanks to the early detection provided by SAST, the development team was able to quickly remediate the issue before deploying the application to production. They fixed the...

Loss due to not following the SAST process

It is difficult to quantify the exact amount of loss that has occurred as a result of not following SAST processes since the impact of a security breach can vary widely, depending on the nature and scope of the breach, the industry in which it occurred, and other factors.

However, data breaches can result in significant financial losses, both for the affected organization and for its customers. In addition to direct costs such as legal fees, remediation costs, and lost revenue, there can be indirect costs, such as damage to reputation, loss of customer trust, and decreased shareholder value.

According to a 2021 report by IBM, the average total cost of a data breach was $4.24 million in 2021, up from $3.86 million in 2020. This includes costs such as investigation and escalation, notification and communication, legal and regulatory expenses, and remediation and recovery.

Furthermore, the report found that the longer it took to detect...

Summary

In conclusion, SAST is a crucial process in software development that helps identify security vulnerabilities early in the development life cycle. By analyzing the source code of an application for potential security issues, SAST tools can help developers fix issues before they are deployed into production, reducing the risk of security breaches.

SAST offers several benefits, including early detection of vulnerabilities, cost-effective security testing, and the ability to identify security issues in third-party code. However, it also has limitations, including the potential for false positives and false negatives, and the inability to detect certain types of security issues.

Despite these limitations, SAST is a critical component of a comprehensive application security program. It should be used in conjunction with other security measures, such as SCA and manual penetration testing, to provide a multi-layered approach to application security.

Implementing strong SAST...