Vulnerability management is undeniably a key part of any organization’s cyber risk strategy. Yet, despite regular patching and constant monitoring for new threats, attackers still manage to exploit entry points that security teams either overlook—or never even knew were there.
This article explores external attack surface management (EASM) and how it extends beyond traditional vulnerability management to give organizations a more complete view of their security gaps and vulnerabilities.
EASM vs. Vulnerability Management
External Attack Surface Management (EASM) and vulnerability management are often conflated, but they serve distinct and complementary roles in a cybersecurity strategy. The key difference lies in their scope. EASM begins with the assumption that an organization has unknown or unmanaged assets; based on this premise, it establishes a foundation in continuous discovery.
Gartner reports that shadow IT makes up 30-40% of IT spending in large organizations, with 69% of employees intentionally bypassing cybersecurity measures. EASM solutions scan for all internet-facing assets, including shadow IT, and assess exposures that go beyond just known CVEs. By uncovering these hidden risks, EASM helps organizations prioritize threats and implement effective mitigation strategies.
On the other hand, vulnerability management operates within the boundaries of a known asset inventory. It scans these identified systems for recognized vulnerabilities, and focuses remediation efforts based on established data. So while both are important, vulnerability management relies on what is already known, whereas EASM seeks to illuminate what isn’t.
The Shortcomings of Vulnerability Management
The key difference between EASM and vulnerability management is visibility (or lack thereof). Vulnerability management is limited to known assets, leaving blind spots where systems have been forgotten, misclassified, or never documented in the first place. While vulnerability management is a crucial aspect of cybersecurity, it falls short when assets go unnoticed or are overlooked.
For example, organizations often rely on internal CMDBs or IT-owned inventories as a single source of truth. But over time, human error and process drift can lead to overlooked assets: decommissioned servers, misconfigured cloud buckets, unregistered web applications, and the like.
These forgotten components become orphaned, unpatched, and vulnerable, with critical services potentially running outdated configurations—all while new domains and servers spin up under the radar of IT and security teams. The consequences are often disastrous: almost 60% of organizations that experienced a data breach in the past two years attribute the incident to a known vulnerability that had not yet been patched.
How EASM Fills the Blind Spots
You can't secure what you can't see. This is where EASM solutions come in, providing the following capabilities to close that visibility gap:
- Continuous Discovery: EASM solutions use automated crawlers and DNS records to map every exposed, public-facing asset—even those outside IT’s purview.
- Security Validation Platform: By continuously assessing your risk posture through simulations of real-world attack scenarios across your entire attack surface, EASM solutions enable security teams to stay ahead of advanced and emerging threats.
- Contextual Prioritization: EASM solutions correlate asset criticality, traffic patterns, and threat intelligence to rank the highest-risk exposures ahead of known CVEs.
- External Validation: By simulating attacker reconnaissance efforts, EASM solutions validate which discovered assets actually respond—and which vulnerabilities are exposed and exploitable in the wild.
- Integrations: EASM solutions feed discoveries back into vulnerability management and ticketing systems so that every newly uncovered asset enters the organization’s patch cycle.
Five Key Uses for EASM
The following guidelines and insights can help security teams strengthen their defenses against both known and hidden threats.
Map Continuously
Security teams traditionally rely on penetration tests to identify vulnerabilities and map exposures across their environments. While highly effective, these tests are costly and resource-intensive, often disrupting operations and consuming the security team’s bandwidth—even when external firms are hired for red teaming. As a result, penetration tests are typically performed on a quarterly basis.
In contrast, EASM solutions can be configured to automatically scan environments continuously, without requiring manual effort or intervention; this allows security teams to have them scanning all the time.
Reconcile Inventories
As previously mentioned, CMDBs and IT asset inventories are often seen as authoritative sources that reflect the full state of an organization’s environment. However, they typically only provide a partial list of known configurations and assets. By integrating an EASM solution that automatically scans and reports its findings, IT and security teams can streamline the process of updating these data sources, providing a more accurate and comprehensive view of their environments.
Prioritize by Exposure
In an ideal world with unlimited budgets and resources, security teams would have everything they need to cover all their bases. However, even in the largest enterprises with substantial resources, teams are often stretched thin and must prioritize their efforts.
By focusing on assets with high internet traffic or sensitive data, you can ensure that your most critical, sensitive, and high-value assets are protected. EASM solutions offer the visibility and insights necessary to make this prioritization possible.
Close the Loop
Integrating EASM alerts into your vulnerability remediation workflows allows you to close the loop on your security efforts. A robust EASM solution will seamlessly integrate with your existing security stack, providing comprehensive coverage that scales with your infrastructure.
Empower Governance
Without established processes and metrics for continuous improvement, security teams struggle to track their progress. By defining SLAs for onboarding new assets into both EASM and vulnerability management workflows, teams can strengthen governance efforts and drive ongoing improvements in their security programs.
EASM and vulnerability management work together to deliver more comprehensive cyber defenses for organizations. See how Outpost24’s EASM solution could enhance your organization's digital resilience – map your attack surface for free.
