Best practices for effective attack surface analysis

An application’s attack surface is the sum of points where it might be vulnerable to bad actors. It consists of all the paths in and out of the application. Identifying vulnerabilities is vital to mitigating threats because any access point is a potential entry point for an attack.

An attack surface analysis, which is critical to this mitigation strategy, is the process of identifying and assessing the potential vulnerabilities and risks in a software system or network.

When performing an attack surface analysis, we must consider the different components, interfaces, and communication paths bad actors could use to access or attack a system. Some essential aspects include:

• Assessing the potential vulnerabilities

• Identifying the attack vectors

• Prioritizing the risk

• Implementing mitigations

• Continuous monitoring

• Community support

• License compliance

• Supply chain security

A thorough analysis strategy is necessary to ensure we don’t overlook any aspect of a system’s security posture. This article reviews several best practices we can implement to make an attack surface analysis more effective.

Attack surface analysis best practices

This section will explore best practices for performing an attack surface analysis. But first, let’s review how to conduct an attack surface analysis.

How to conduct attack surface analysis

The analysis process consists of two primary steps: 

• Mapping out the attack surfaces. 

• Ranking the severity of potential breaches. 

Let’s explore each step in more detail.

Map out attack surfaces

Mapping out attack surfaces involves examining the different interaction points with an application. This includes APIs, databases, user input forms, authentication tools, and other potential services. We also need to determine attack vectors — the methods or paths a bad actor can use to introduce malware, ransomware, and viruses into the system. Attack vectors might include email attachments, pop-up windows, or instant messages. 

Vulnerabilities often emerge from the need to open interaction pathways between applications and users, data sources, and other applications. These paths become more complex when they use microservices, open source, and third-party components. These components communicate via APIs or other channels, making their access points plentiful. Without adequate authentication, these entry and exit points represent a substantial portion of our attack surface. 

Incorporating open source components must be done with appropriate care. Don’t assume that a component is secure. Investigate each component to confirm that it’s free from vulnerabilities. Validating that open source code is from a trusted source is another smart mitigation step. Remember that any vulnerability in these components becomes part of the application’s attack surface.

We can divide the mapping process into several categories — including databases, networks, and applications. Once we identify vulnerabilities in these areas, we should confirm whether the components are accessible from the internet or other external sources. Although many components aren’t externally facing, they may be accessible through an external source if access is breached. 

Attack surface mapping and analysis have traditionally been relegated to the end of the development cycle. However, incorporating attack surface analysis as part of our DevOps workflow provides the advantage of identifying attack points when introduced. We can work through an application’s architecture and create a detailed breakdown of different attack surfaces.

Rank the severity of attacks

Once we’ve identified an application’s attack surfaces, we need to rank the severity of the threats. These severity rankings are based on the likelihood of exploitation and the severity of this potential exploitation.  We might rank them based on aspects like access to sensitive data and exposure — especially with publicly available applications.

Data sensitivity is one factor that informs severity rankings. Highly sensitive data — credit card numbers, financial information, or health information — would be damaging if released publicly. Other information might not be as sensitive but should still remain confidential. The least sensitive category is publicly available information, which includes anything the organization is willing to disclose. 

Severity assessments also consider the access controls used to protect systems from malicious viruses or ransomware. The stronger the security controls are, the less vulnerable they are to attack.

Outward-facing systems are the most vulnerable, so extending the analysis to these applications is crucial. Bad actors can breach the outer layer and move freely through the system if you don’t adequately secure these applications. Once inside, they can find deployment points for attack vectors much more easily.  

Threat modeling

Threat modeling is a great place to start ranking and analyzing the severity of the attacks, as it involves determining the priority of any given threat by weighing several factors — such as the likelihood of attack and potential loss if an attack is successful. 

Threat modeling starts by looking at the assets from the attacker’s perspective. By looking at the likelihood of malicious actors targeting a particular attack point, we can determine potential attack points and vectors and respond accordingly. 

Threat modeling outlines three key factors to help prioritize which vulnerabilities should be addressed first:

• Greatest vulnerabilities

• Most likely threats

• Mitigation strategies and possibilities

Considering these factors ensures that we can balance the ease with which we could mitigate a threat with the danger that potential attack vectors pose. This process helps clarify whether it’s better to address fast, easy-to-rectify issues first or focus on the more high-risk threats that take longer to resolve. Balanced decision-making is a key to priority — and threat modeling is key to balanced decision-making. 

Implement vulnerability scanning 

A vulnerability scanner is a testing tool that reviews code, networking, configurations, and more for possible vulnerabilities. Using a vulnerability scanner throughout the development lifecycle allows us to automatically identify, and more easily correct, vulnerabilities before they’re committed. Additionally, it helps secure the software supply chain, as we can scan open source code and packages for vulnerabilities. 

Snyk’s vulnerability scanning capabilities allow us to scan network and open source applications for vulnerabilities. Then, tools like Snyk Code and Snyk Open Source allow us to implement vulnerability scanning in our development pipelines by scanning code while it’s being written. 

Introducing vulnerability scanning supports a shift-left approach to security, helping us reduce our attack surface. 

Additional best practices for attack surface analysis 

In addition to implementing vulnerability scanning and following the attack surface analysis steps outlined above, we can follow other best practices to keep our applications secure.

Use categories as a framework for mapping attack surfaces

Breaking down the mapping process into categories — such as network, database, or API — makes analysis more manageable. These categories provide a framework to examine the attack surface, which is useful in structuring attack surface discovery. 

While it’s possible to accomplish this manually, automated scanning tools, like those from Snyk, can scan the environment and identify potential attack points/vectors. In addition, these tools detect weaknesses that make the attack point/vector more vulnerable. 

Make attack surface discovery a continuous process

Since the system is changing, with components and capabilities continuously being added, you should continuously perform attack surface discovery to secure the system. 

Attack surface discovery should be a continuous process to stay ahead of potential threats and vulnerabilities. Here are some ways to make it a continuous process:

1. Regular vulnerability assessments: Conduct regular vulnerability assessments of your systems and applications. This will help you identify and address potential vulnerabilities before they can be exploited.

2. Penetration testing: Conduct regular penetration testing to simulate real-world attacks and identify potential security weaknesses in your systems and applications.

3. Continuous monitoring: Implement continuous monitoring of your systems and applications to detect potential security threats in real time.

4. Employee training: Provide regular employee training on cybersecurity best practices, including identifying potential attack surfaces and reporting suspicious activity.

5. Keep up with industry trends: Stay up-to-date with the latest trends and developments in cybersecurity, including new attack methods and vulnerabilities.

Work to secure your supply chain

Supply chain security is often overlooked but proves important. Securing your supply chain means staying alert to vulnerabilities introduced through partnerships with other organizations, such as vendors or suppliers. For instance, bad actors can insert vulnerabilities into code residing in public software repositories, increasing the attack surface of any organization that uses this code.  

Get involved in the cybersecurity community

Participating in the cybersecurity community can be a useful way to gain information about security trends and possible risks. Organizations such as the OWASP, OpenSSF, SANS Institute, and ISC2 promote the exchange of information between organizations and can raise the alarm about emerging issues or hacking strategies. 

Ensure license compliance

Ensuring you’re compliant with your licenses can also minimize the attack surface. License compliance means deploying the software in a means consistent with your license. When in license compliance, the security patch sent by the licensee will correct vulnerabilities. However, if the product is not deployed in a way consistent with the license, then patches may not apply correctly. 

Additionally, open source applications may make use of applications that require licenses. You’re expected to acquire your own licensing of these applications, and failing to do so means risking both security vulnerabilities and the possibility of litigation. 

Attack surface analysis with Snyk

With the continued expansion of digitalization and cloud implementation of services, IT organizations are faced with the issue of how to protect an ever-growing attack surface. Identifying an organization’s attack surface has become an arduous task, even without the work of mitigating vulnerabilities. Points of attack and attack vectors are only increasing, and bad actors now exploit vulnerabilities more frequently and creatively than ever before. 

Protecting the attack surface requires continual scanning of the entire infrastructure. The best scanning systems are automated to include artificial intelligence and machine learning that incorporates IT community knowledge and makes it actionable. 

Snyk provides the ability to incorporate best practices to protect the attack surface in the hands of developers by detecting third-party dependency issues in open-source components. Explore Snyk’s resources and watch a live demo to learn more about its powerful capabilities.