What is External Attack Surface Management (EASM)?
The Growing External Attack Surface
Historically, IT security strategies have focused on establishing robust perimeter defenses, using internal networks and firewalls. However, attackers don’t always need to infiltrate these perimeters, as externally hosted assets present easy targets. Securing this external attack surface poses a significant challenge for security teams.
Modern digital systems have a broad reach, with numerous assets deployed beyond the protected network edge. This external digital footprint, which includes online interactions among employees, customers, and third parties, can be much larger and more difficult to safeguard than the internal network.
This challenge escalates as businesses undergo digital transformation and enable remote users to engage via web applications and services. Organizations expand their digital assets, many of which are hosted outside the firewall or in the public cloud, such as on cloud infrastructure or mobile app stores.
Moreover, developing these applications and services often involves third-party products and features, including data, infrastructure, and code. Third-party vendors and service providers often build their functionalities on top of other providers (i.e., fourth parties). Organizations must include these assets in their external attack surface strategy, even if they lack detailed knowledge.
Key Challenges Around the External Attack Surface
Organizations face several challenges when attempting to map and protect the external attack surface:
Excessive Data from Automated Tools: Organizations frequently use multiple tools to monitor the attack surface, leading to an abundance of data and alerts that can drain resources. Security tools should prioritize and triage alerts, providing actionable insights.
Distributed IT Ecosystems: Organizations no longer have a traditional, well-defined network perimeter. Today’s IT ecosystems consist of multiple endpoints and assets dispersed across various locations and devices. This ecosystem may include a core network, regional offices, subsidiaries, third-party hosting providers, and business partners located outside the organization’s firewalls.
Shadow IT: Besides the increasingly distributed nature of IT ecosystems, organizations also confront serious risks posed by shadow IT – unauthorized use of IT systems, software, devices, services, and applications. While shadow IT can boost employee productivity and innovation, it introduces significant security risks that may lead to data leaks and potential compliance violations. The primary issue is not that employees use a particular tool, but that they introduce these tools without notifying the IT or security department. Shadow IT results in security teams being unaware of compromised assets already exploited by attackers. This lack of visibility, inventory, and comprehensive security coverage leaves organizations vulnerable.
External Attack Surface Management (EASM) Use Cases and Capabilities
EASM tools help organizations map their external attack surface, uncovering and managing potential vulnerabilities and security weaknesses in external and internal-facing assets and detecting unknown infrastructure-based vulnerabilities. EASM should be integrated into your overall cybersecurity strategy and used alongside tools like cloud security posture management (CSPM) and vulnerability scanners. EASM should work within your security stack to identify, prioritize, and remediate misconfigurations and vulnerabilities.
Common EASM use cases include:
Merger and acquisition (M&A) pre-deal diligence and post deal integration : EASM helps organizations understand the digital assets landscape and the associated risks that the acquiring organization may inherit from an acquired company.
FDA premarket submission and post-market monitoring: EASM can play a crucial role in supporting organizations within the medical device and pharmaceutical industries throughout the FDA premarket submission and post-market monitoring processes
Supply chain or third-party risk: EASM extends visibility to cover supply chain vulnerabilities and third-party threats, supporting assessments that evaluate the organization’s risk exposure.
Subsidiary risk: EASM provides visibility into digital assets across various subsidiaries, enabling a more comprehensive risk assessment.
Digital asset discovery and inventory: EASM helps organizations discover unknown digital assets such as websites, domain names, IP addresses, cloud services, and SSL certificates across various environments, including cloud, local IT, operational technology (OT), and IoT. EASM maintains an up-to-date inventory of identified assets.
Remediate vulnerabilities and reduce exposures: EASM prioritizes the remediation of exposures, including misconfigurations, unpatched vulnerabilities, and open ports, based on risk level and severity.
Cloud security and governance: EASM assists organizations in identifying public assets across cloud vendors to enhance cloud governance and security. The aim is to discover cloud assets the organization is unaware of and apply appropriate protections to secure them.
Sensitive data leakage detection: EASM monitors for data leakage, including credential leakage and sensitive data exposures occurring through cloud applications and collaboration tools used by third parties and employees.
Key EASM capabilities include:
Monitoring: Continuous scanning of various external environments, such as external-facing on-premises infrastructure, cloud services, and distributed ecosystems like IoT infrastructure.
Asset discovery: Identifying and mapping unknown external-facing assets.
Analysis: Assessing asset attributes to determine the risk level of each asset and whether it is vulnerable or displaying abnormal behavior.
Prioritization: Prioritizing vulnerabilities and risks, generating alerts based on prioritization analyses.
Remediation: Providing actionable insights for mitigating prioritized threats and integrating remediation with solutions like ticketing systems, security orchestration, automation and response (SOAR) solutions, and incident response tools.
Attack Surface Management with Praetorian’s Managed Service — Chariot
Visibility alone is insufficient to minimize risk and withstand attacks. Organizations need to understand their attack surface and rank their assets based on how an attacker would prioritize and execute their attacks. Chariot combines intelligence from full-time offensive security operators with asset discovery, continuous assessment, and process improvement to reduce risk across your ever-expanding digital landscape. You can identify, analyze, manage testing scopes, and track testing results in one place for a complete asset inventory. Once identified, asset risk can be ranked, coverage gaps addressed, and remediation resources assigned. With Chariot, organizations will have a comprehensive understanding of their attack surface and be equipped to effectively resist attacks.