Cybersecurity Audit Types Explained

In this post, we’ll cover three types of code security audits, the difference between internal vs. external audits, and how to audit security throughout the software development lifecycle (SDLC).

What are the types of cybersecurity audits?

Three types of cybersecurity audits are:

1. Threat modeling

2. Vulnerability assessments/penetration testing

3. Security compliance audits

Let’s take a deeper look at each security audit type.

1. Threat modeling

Modern software development depends on achieving the “magic three” outcomes: faster releases, shorter cycles, and higher quality code. In order for code to be of high quality, it needs to be secure, so cybersecurity must be integrated with the development cycle in a way that does not hinder developers’ ability to release code fast.

The key to implementing application security without disrupting DevOps workflows is to assess security risks from the start using threat modeling. This process examines business requirements and logic to uncover any areas that might pose security risks. 

In particular, threat modeling examines four areas:

• The design of system operations and data flow

• The risks and what areas are exploitable

• How to defend against each exploit

• How well threat modeling and defenses perform

Threat modeling is an ongoing process that is never fully complete, but it’s the first step towards baking security into your development process, and following cybersecurity hygiene best practices.

2. Vulnerability assessments/penetration testing

Vulnerability assessments work on the principle that it’s easier to remediate vulnerabilities if they are uncovered before they reach a runtime environment. By using static analysis and source code analysis tools in code security audits, organizations can uncover and remediate the most common and risky types of vulnerabilities, including injection attacks and third-party vulnerabilities. Furthermore, they can ensure that code meets compliance and licensing requirements before it’s released.

Penetration testing is a form of ethical hacking where internal or external testers attempt to uncover vulnerabilities by simulating a cyberattack against an environment.

Penetration tests come in three forms depending on how much visibility the tester has into the code: white box, black box, and gray box testing.

White box testing

White box testing refers to penetration testing where the tester or tool has knowledge of the software's internal working structure and understands what it is supposed to do. With this knowledge, testers can break code down into the smallest functional components and then test each component (“unit testing”). Testers can also examine specific pieces of code to ensure there are no errors such as loopholes in the business logic. White box testing can be automated and executed in the CI pipeline using tools such as Snyk Code.

Black box testing

Black box testing refers to penetration testing where the tester or tool has no knowledge of the software’s internal working structure. As such, it simulates how an attacker would attempt to exploit flaws in a system to breach it. Techniques for executing black box testing include:

• Fuzzing, which tests API services or web interfaces with random or customized input;

• Syntax testing, which checks for invalid inputs or outputs, such as wrong syntax or exposing sensitive data;

• Exploratory testing, where analysts uncover hidden security issues, report them, and suggest fixes;

• Data analysis, which analyzes system logs or responses to uncover any suspicious behavior or potential security issues.

One of the most popular black box testing methods is dynamic application security testing (DAST), which can happen manually or automatically. Unlike static application security testing (SAST) tools, which analyze the source code itself, DAST does not require insight into the software’s internal working structure so it can be conducted externally. While DAST has a lower rate of false positives than SAST tools because it only uncovers vulnerabilities that are exploitable, it's difficult to ensure the entire code base has been evaluated, and it requires absorbing the costs of deploying applications in order to carry out DAST tests.

Gray box testing

Given that white box and black box testing both have their own advantages and disadvantages, testers often use gray box testing to apply the best parts of each testing method. For example, gray box testing simulates how an attacker would view an application, while using knowledge of the application to uncover vulnerabilities. If a tester knows the language an application is written in, he or she can use that knowledge to uncover common vulnerabilities in that language. 

3. Security compliance audits

Applications that handle sensitive data that’s protected under HIPAA, PCI, or other standards may need special considerations to ensure they are compliant. In particular, they should be regularly tested for new or previously undetected vulnerabilities. Snyk offers a PCI compliance service that uses compliance-as-code and other methods to ensure compliance (and provide a trail for auditors).

Internal vs external cybersecurity audits

The types of cybersecurity audits include both internal and external audits. Internal audits, such as those completed by developers and security teams, are more conducive to white box testing since they only expose source code to internal teams. External auditors can then apply black box tests from an attacker’s perspective.

A variety of new tools are available to both internal and external auditors. Internal auditors can take advantage of advanced SAST tools like Snyk Code to automatically uncover vulnerabilities within code. External auditors can then take advantage of modernized penetration testing tools, along with sophisticated artificial intelligence (AI) powered tools like security analysis, which monitor logs and requests to uncover any unusual patterns that could indicate a vulnerability.

Auditing security throughout your SDLC

Security traditionally has happened at the end of the SDLC, but DevSecOps approaches incorporate security from the start. By continuously auditing security throughout your SDLC, it’s possible to uncover vulnerabilities and apply fixes before they impact production environments. Let’s consider how audits address each aspect of the modern software application:

Open source audits

The majority of code in a modern application may actually be in open source libraries that are consumed by the main application. These libraries themselves need to be audited since they may introduce vulnerabilities that are unknown to developers. Snyk offers open source audits to help uncover vulnerabilities and manage your open source software. Furthermore, Snyk Open Source helps ensure open source usage is compliant with the relevant licensing requirements.

Code security reviews

Code reviews are a critical part of the SDLC since they help uncover the primary causes of poor code quality, including security issues. They are slightly different from audits since they are typically conducted by developers themselves and address all aspects of code quality, whereas audits specifically address security risks and may be conducted by security teams or external auditors. 

Container image audits

Since modern developers typically specify container configurations along with their application, they need to audit their container management processes. Snyk Container is designed to help with the security aspects of containers, including selecting a secure base image, automated base image upgrades, and ongoing monitoring for new vulnerabilities. This allows developers to confidently use containers without needing advanced operating systems expertise.

IaC template audits

The DevOps approach means developers are increasingly responsible for configuring the infrastructure on which their containers will be deployed. From a security perspective, this means implementing IaC best practices such as operating on a “least privilege” basis, segmenting network traffic, and encrypting data in transit and at rest. 

Related Links

• Cloud Native Application Security (CNAS) | Snyk

• Code Security Auditing 101 | Snyk

• Application Security Testing - Top questions answered | Snyk

• Best Practices for Cybersecurity Audits | Snyk

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