External Attack Surface Management (EASM): Managing Digital Risk

An external attack surface, or digital attack surface, is the sum of an organization’s internet-facing assets and the associated exploitable attack vectors.

Consider the following scenario: a large online retail company sells its products through its e-commerce platform and wants to ensure the security of its online presence and customer data. However, the retailer ignores a vulnerability in their web server software, and malicious actors exploit it to gain unauthorized access to customer data. 

The retailer could have avoided this by regularly assessing and reducing their external attack surface to protect its online business and customer information proactively. 

Recognizing the importance of external attack surface management and taking proactive steps to secure digital assets prevents security breaches like the one illustrated above and their inevitable consequences.

Keep reading to discover:

• What is external attack surface management (EASM)?

• When should you use EASM?

• Four EASM solutions.

• How to implement EASM successfully.

• How Snyk helps with EASM

What is external attack surface management (EASM)?

EASM is a modern approach to cybersecurity focusing on identifying, managing, and mitigating risks posed by exposed assets within an organization's digital perimeter. This perimeter consists of all the externally visible points (attack surfaces) where an attacker can interact with an organization's digital assets.  

According to Gartner, EASM refers to the services deployed to discover internet-facing enterprise assets and systems and associated exposures, which include misconfigured public cloud services and servers, exposed enterprise data such as credentials, and third-party partner software code vulnerabilities that adversaries could exploit. 

EASM provides valuable risk prioritization, context, and actionable information through regular or continuous monitoring and discovery of external-facing assets and systems. 

External attack surface management should be a top priority for security teams and risk managers. Components of EASM can be managed at scale with ASPM tools, which aggregates data about assets, helps discover assets and tools within your organization and the vulnerabilities affecting them, and prioritizes fixes based on wider business risk. 

What are the components of EASM?

EASM involves several key components and activities to manage an organization's exposure to external security threats. The components of EASM typically include:

• Asset discovery and monitoring: Identifying, cataloging, and continuously monitoring all digital assets and resources accessible from the internet, including domains, IP addresses, web applications, APIs, cloud services, and more.

• Risk assessment: Evaluating the risks associated with the external attack surface. This assessment helps organizations prioritize their security efforts based on threats' potential impact and likelihood.

• Risk mitigation: Implementing measures to reduce and mitigate the identified risks and vulnerabilities, including patching, access control, configuration changes, and security best practices.

Continuous monitoring and adaptation: Ongoing surveillance and real-time monitoring of the external attack surface, with the ability to adapt and respond to changes in assets, vulnerabilities, and emerging threats.

When should you use EASM?

You should consider using EASM in the following scenarios:

1. Rapidly evolving digital footprint: If your organization's digital footprint is expanding rapidly due to digital transformation initiatives, mergers and acquisitions, or adopting cloud services, then EASM becomes crucial. EASM can help you continuously monitor and manage your increasing and evolving external attack surface. 
   With the ever-changing landscape of digital assets, EASM ensures that you can adapt to new security challenges as they arise.

2. Compliance with regulatory requirements: In some cases, regulatory bodies may require EASM. For instance, if you're subject to regulations like the General Data Protection Regulation (GDPR) or the California Consumer Privacy Act (CCPA), you may need to demonstrate that you have controls to protect against external threats. 
   EASM can provide the necessary visibility and control to meet these requirements. It helps you proactively identify and mitigate security risks to safeguard sensitive customer and user data.

In addition to the above situations, EASM is valuable in organizations that want to maintain a strong cybersecurity posture, especially in the face of evolving cyber threats and a constantly changing digital landscape. Proactively managing the external attack surface is essential to reduce the risk of data breaches and security incidents.

Two key indicators that your organization needs EASM

Two key indicators that your organization needs external attack surface management are:

1. Frequent security incidents: If your organization experiences a high frequency of security incidents, such as data breaches, cyberattacks, or unauthorized access, it's a strong indicator that you may need EASM. EASM can help you proactively identify vulnerabilities and reduce the risk of security incidents.

2. Unmanaged shadow IT assets: Unmanaged or unauthorized IT assets and services within your organization (often called "shadow IT") can create security blind spots. EASM can assist in discovering and securing these assets, ensuring that they do not pose security risks to your organization.

Four EASM solutions

Tooling for EASM is crucial in identifying, monitoring, and managing an organization's external attack surface. Here are some common tools used for EASM:

1. Vulnerability scanners: These tools scan your digital assets for vulnerabilities and weaknesses. They help you identify security issues that attackers could exploit. 

2. Penetration testing tools: Penetration testing tools simulate cyberattacks to identify security weaknesses. 

3. Asset management solutions: Asset management tools help you catalog and keep track of all digital assets, including devices, software, and services that are part of your external attack surface. 

4. SIEM solutions (Security Information and Event Management): SIEM solutions collect and analyze security-related data from various sources to provide real-time monitoring, threat detection, and incident response capabilities. 

These tools are essential for identifying potential vulnerabilities and threats and responding to security incidents effectively. Implementing a combination of these tools can help organizations enhance their cybersecurity posture and reduce risks associated with external attack surfaces.

How to implement EASM successfully in your organization 

To successfully implement EASM in your organization, follow these key steps:

1. Establish a dedicated team: Form a dedicated team responsible for EASM. This team should include cybersecurity, asset management, and risk assessment experts. Clearly define roles and responsibilities within the team to ensure that EASM tasks are effectively carried out.

2. Choose the best tooling for you: Select the appropriate EASM tools and solutions that best fit your organization's needs. These tools should include asset discovery, vulnerability assessment, penetration testing, and asset management systems. Ensure the chosen tools can provide real-time monitoring and adapt to the evolving threat landscape.

3. Adopt a risk-based, asset-first approach: Prioritize your efforts based on risk assessment. Identify critical assets and focus on them first. Not all assets have equal value, so allocate resources to protect those most essential to your organization's operations.

4. Promote a security-first culture: Instill a security-first mindset throughout the organization and encourage employees to be vigilant about security. Additionally, conduct security awareness training to educate staff about the importance of EASM and their role in maintaining a secure environment.

5. Stay informed with security intelligence: Keep your team updated with the latest security intelligence. Subscribe to threat intelligence feeds, attend security conferences, and collaborate with industry peers to understand emerging threats and vulnerabilities. This knowledge will help you adapt your EASM strategy to address new challenges.

How Snyk helps with EASM

Snyk is a developer security platform that enables developers to secure their whole application — finding and fixing vulnerabilities from their first lines of code to their running cloud. 

Snyk's products integrate into your development workflow and offer solutions like:

• Snyk Code: Secure your code as it’s written with static application security testing built by, and for, developers. Snyk Code works alongside your developers to prevent vulnerabilities in code reaching production with real time security scanning and fix advice.

• Snyk Open Source: a developer-first SCA solution, helping developers find, prioritize, and fix security vulnerabilities and license issues in open source dependencies.

• Snyk Container: Container and Kubernetes security that helps developers and DevOps find, prioritize, and fix vulnerabilities throughout the SDLC — before workloads hit production.

• Snyk Infrastructure as Code (IaC): Build, deploy, and operate securely in the cloud with security embedded in developer workflows from code to cloud. Snyk IaC provides security feedback and fixes in-line with code across the SDLC and running cloud environments.

Snyk’s support for multiple programming languages and platforms makes it a versatile suite of products for EASM. Using Snyk as part of your EASM strategy, you can proactively secure your digital assets, reduce risks associated with external threats, and maintain a strong cybersecurity posture.