Last updated at Fri, 19 Apr 2024 20:12:55 GMT

This article was written by Ethan Smart, Co-Founder and Chief Solution Architect, appNovi (a Rapid7 integration partner).

It's essential for security and IT teams to have a comprehensive view and control of their cyber assets. This is why Cyber Asset Attack Surface Management (CAASM) has received so much attention from security practitioners and leaders.

According to Gartner, “CAASM tools use API integrations to connect with existing data sources of the organization. These tools then continuously monitor and analyze detected vulnerabilities to drill down the most critical threats to the business and prioritize necessary remediation and mitigation actions for improved cyber security.”

What is CAASM?

CAASM provides a unified view of all cyber assets to identify exposed assets and potential security gaps through data integration, conversion, and analytics. It is intended to be authoritative source of asset information complete with ownership, network, and business context for IT and security teams.

Security teams integrate CAASM with existing workflows to automate security control gap analysis, prioritization, and remediation processes. These integration outcomes boost efficiency and break down operational silos between teams and their tools. Common key performance indicators of CAASM are asset visibility, endpoint agent coverage, SLAs, and MTTR.

It’s important to understand assets are more than devices and infrastructure. In a Security Operations Center (SOC), assets include users, applications, and application code. Recognizing the interconnectedness of these assets is key to enhancing the SOC's capabilities. For example, consider a scenario where 1,000 servers have the same vulnerability. Assessing each one individually would be incredibly time-consuming. CAASM enriches cyber asset data to automate the majority of analysis.

For example, when you understand only eight of the 1,000 servers are internet-facing, and of those only two are exposed through the necessary port and protocol for exploitation of the vulnerability, you know which assets have the highest contextual exposure, which are exploitable, and which should be addressed first.

In this blog, we’ll cover how security teams can leverage their existing tech stack for Cyber Asset Attack Surface Management.

Understanding the Attack Surface

Comprehensive attack surface management hinges on a comprehensive understanding of everything that is a target for attackers. In a sprawling enterprise environment, there's an abundance of assets distributed across different networks (e.g. cloud, SDN, on-prem), each with its own set of monitoring and alerting tools. When these security tools don’t interoperate or mesh with one another, security teams lack a complete picture of the attack surface. This fragmented understanding results in the continued siloing of teams and tools and inhibits effective data sharing.

One of the oldest adages in cybersecurity is complexity is the enemy of security—and complexity increases when teams recognize assets as more than devices. Assets are more than just computers and servers connecting on the network, as those assets are used to support applications to drive revenue. Applications also use code, which can be used by multiple applications. Users are assets that operate the business using technology. This complex asset tracking and relationship mapping spans network connections, application and code ownership, and the dependencies and indirect dependencies between applications.

CAASM emerged to address this complexity. CAASM is founded through the consolidation of existing data from all the different network and security tools. For example, by integrating Rapid7's portfolio of products with a security data integration and visualization solution like appNovi, organizations can achieve and maintain full visibility across their entire connected network—including on-prem, Software Defined Network (SDN), and hybrid cloud.

Using CAASM, organizations can leverage analytics to refine search results, identify trends, or disseminate specific information to defined groups or individuals. One common use case with appNovi is identifying vulnerable application servers contextually exposed for exploitation and identifying owners based on login telemetry and notifying the server owner and security. This integrated approach delivers comprehensive attack surface visibility and mapping to enable organizations to address risks and manage vulnerabilities more efficiently. When analytics are coupled with automation tools, such as orchestrators, the SOC is able to focus on threat hunting and less on data analysis. Common examples include asset inventory management and security control gap analysis.

Cyber Asset Inventory and Mapping

To manage the attack surface proficiently, it's essential to discover and map an organization's assets accurately and with the greatest level of detail. Organizations that use Rapid7’s Insight Platform already identify network infrastructure to pinpoint active devices, open ports, and running services. When combined with your other tools’ data through the enrichment capabilities of appNovi, Rapid7’s InsightVM integrates with the entire network and security tech stack to reveal overlooked assets, those that were inadvertently deployed without endpoint detection and response (EDR) agents, and those that require a prioritized response.

Telemetry data can also be leveraged from Rapid7’s InsightIDR to enrich asset data to understand network connections, ownership, and user activity. This relationship and connection mapping supports establishing the relationships between assets and their relevance to applications. With an automated and continuously updated asset inventory enriched by telemetry, IT and security teams not only gain visibility but also develop a comprehensive understanding of each asset’s dependencies and business significance.

Risk Assessment and Prioritization Based on Exposure

Vulnerability scanners and agents help you understand what devices and their software are vulnerable. For teams today to understand the exposure of their vulnerable devices requires sifting through large amounts of network log data. This time-consuming process often inhibits the ability to prioritize devices based on their network contextual exposure. But when telemetry sources are abstracted and converged with cyber asset data, contextual exposure analysis becomes a simple and automated analysis. That’s why data convergence in appNovi with Rapid7’s platform compiles network, asset, and vulnerability data into a comprehensive and easily accessible format.

This powerful data management capability means teams efficiently and accurately identify the devices that are the most vulnerable and exposed to both external threats and lateral movement from within the network. With this level of enrichment, security teams can quickly identify the handful of assets that require immediate prioritization to support an effective remediation strategy.

Identifying and Managing New Assets

Monitoring the attack surface involves leveraging a diverse set of tools to identify new assets within an organization's digital ecosystem. It is vital to utilize comprehensive asset discovery tools, vulnerability scanners, and other solutions to gain a holistic view of the digital infrastructure.

However, some infrastructure is ephemeral or may be inaccessible to all monitoring tools, in which case telemetry data sources and other SIEM data can be used to identify new assets. This aggregation, enrichment, and analysis can feed into other actions whether it be as simple as email notifications of results or triggering specific automated actions.

Creating Closed-Loop Remediation

When an authoritative source of detailed asset data is established standard searches can be run to provide consistent results and define specific outcomes. As an example, many organizations want to prioritize appropriate EDR agent and Rapid7 IDR agent installations across their application infrastructure.

To achieve this functionality, security teams define what constitutes appropriate security controls and search for all assets that do not meet the criteria. The results can trigger playbooks or workflows to create automated remediation notifications. In instances where orchestrators can install agents, those assets without agents can be automatically remediated in a self-healing loop.

By integrating Rapid7's platform with appNovi, businesses gain actionable insights into the changes that occur across their attack surface with the ability to implement streamlined remediation.

Best Practices for Cyber Asset Attack Surface Management

Maintaining a robust attack surface management initiative is essential—automating as much of it as possible is what will result in efficiencies for the SOC. There are several best practices for organizations that want to undertake the initiative to uplevel security operations with Cyber Asset Attack Surface Management.

Different data, same problem
Rarely is all data in the same format. Even more rarely does all data provide the same match values of assets. For CAASM to be effective, ingestion and data convergence must facilitate data normalization through abstraction. This needs to be done through unique identifiers. Without integrated data feeds that support the wide variety of data structures and vendor nuances, you’ll end up back in an Excel spreadsheet that effectively only saves you a SIEM query.

Less is hard
There are many different data points about assets. All the asset attributes must converge into a single asset profile. Without this capability, security teams will be sifting through duplicate records providing two different perspectives on the same asset which often leads to partial resolution or inaction. To be effective, the SOC needs a high-fidelity source of data and not several incomplete profiles of the same asset.

Where is it?
Complete asset inventories are helpful to satiate compliance requirements, but without context, all assets will be viewed based on an objective data point. Because you have network data, you should be able to apply your network context to it and make the asset subjective. An external-facing asset with a medium risk is more important than a high risk asset buried behind several network security controls. Your tools already monitor and have network and business context—that telemetry and enrichment need to extend to assets.

What is it?
Every enterprise has applications. Few know how many they have deployed in their network. Using application data sources can help delineate and track application servers and what they are direct and indirect dependencies of. The business importance of an asset helps not only in prioritization, but telemetry such as logins can expedite ownership identification.

Overcome the complexity of asset tracking

By leveraging the power of CAASM, organizations can overcome the complexity of asset tracking and relationship mapping, optimize their security workflows, and effectively manage the evolving threat landscape. The tooling already exists, all that’s required is the integration and data convergence capabilities for you to uplevel the SOC.

Watch appNovi’s video on CAASM capabilities with Rapid7 today to understand this comprehensive and proactive approach to cybersecurity.