Attack Surface Monitoring Guide for Security Teams

The rising threat of cybercrime, projected to reach an astonishing $13.82 trillion by 2028, is largely attributed to the expanding attack surface. This signals that organizations are more vulnerable than ever.

Assuming your organization is safe, without ongoing visibility is dangerous. That’s because every digital asset poses a threat, whether a new tool or forgotten assets. Security and Operations Center (SOC) teams require real-time insight, which is why attack surface monitoring is crucial.

In this guide, we define what it is, explain why it matters, outline attack vectors, provide best practices, and answer your most frequently asked questions.

What is attack surface monitoring

Attack surface monitoring continuously discovers, classifies, and assesses all internet-facing digital assets to identify and mitigate potential risks before attackers can exploit them.

​Attack Surface Management (ASM) provides a more comprehensive remediation lifecycle in comparison. Monitoring forms part of this, providing the foundation for visibility in a robust security program, which encompasses the discovery and assessment phases with 24/7 coverage.

Why attack surface monitoring matters

Attack surface monitoring provides organizations with around-the-clock visibility, enabling fast response times and mitigating the impact of breaches. It shifts defenses to an attacker’s perspective, prioritizing external risks that can be exploited for initial access.​

With the expansion of remote and hybrid workforces and the integration of SaaS tools, cloud services, and DevOps, security gaps often go undetected for months.  Additionally, regulatory and compliance pressures make attack surface monitoring critical today.

1. Rising external threats

​Attackers increasingly target easily exposed cloud instances and neglected endpoints. With nearly 82% of all breaches involving cloud data, organizations must prioritize continuous monitoring of these digital-facing assets, as they pose the highest risk for initial access.

2. Combatting Shadow IT & Sprawl

Attackers move faster than internal audit schedules because rapid cloud adoption is leading to forgotten assets (or Shadow IT), which lack proper security controls. Attack surface monitoring will immediately detect these hidden assets, bringing them into your security scope before an attacker can exploit them. 

3. Pressures from regulators

Compliance frameworks such as PCI, DSS, HIPAA, and GDPR require ongoing continuous vulnerability assessments and asset inventory logging. Implementing these provides auditable proof of due diligence and places greater accountability on organizations that fail to detect external risks. 

4. Operational cost savings

Automated attack surface monitoring is operationally beneficial in that it reduces the time and resources SOC teams spend on manual asset discovery and time-boxed vulnerability scanning.

Additionally, proactive patching prevents financial damage from data losses, regulatory fines, and reputational harm.

Common attack vectors and assets

Attack surface monitoring uncovers external entry points that criminals rely on for easy access. These include overlooked web applications, unprotected APIs, or leaked credentials, which can be used maliciously.

1. Cloud infrastructure

Misconfigurations or data exposures within cloud infrastructures can lead to large-scale data breaches. The complexity of a shared responsibility model often leads to this oversight, particularly regarding customer security duties such as access controls, which attackers are eager to exploit.

2. Credential exposure

Leaked credentials are a primary enabler of unauthorized access, often being bought and sold on the dark web. Continuous monitoring helps to alert teams to exposure, prompting immediate actions such as credential rotation and enforcing Multi-Factor Authentication (MFA).

For proactive monitoring of leaked credentials and dark web sales, explore UpGuard’s Threat Monitoring solution.

3. Misconfigured endpoints

Assets inadvertently left open and exposed without proper security controls, such as legacy systems, Internet of Things (IoT) devices, or outdated servers, are considered misconfigured endpoints. These assets are low-effort targets to attackers and require routine, external configuration checks to prevent exploitation.

4. Forgotten endpoints & legacy tech

This category includes outdated, unpatched servers, forgotten IoT devices, or development and test environments that are left running after their primary purpose has ended. These systems are often easily overlooked but represent a major and easily exploitable entry point for a persistent attacker.

4. Public-facing APIs

Public-facing Application Programming Interfaces (APIs) act as a direct gateway to an organization’s data. Attackers actively scan for unprotected or poorly documented API endpoints, and once they are found, they pose a significant risk for large-scale data exfiltration.

Best practices to implement attack surface monitoring

This is your step-by-step guide to integrating attack surface monitoring effectively into your security operations: 

Identify all internet-facing assets

Utilize specialized discovery tools to identify and track every external asset, including shadow IT and unknown domains. This creates a central asset inventory, receiving real-time updates from the monitoring solution to act as a single source of truth for complete visibility.

Rank vulnerabilities by criticality

Use risk-based prioritization by considering key elements, such as data sensitivity, the availability of a public exploit, and the potential impact of a successful compromise. This process addresses vulnerabilities with the largest immediate impact first.

Automate patching and validation

Integrate monitoring alerts directly with patch management or DevSecOps pipelines for continuous, automated updates. This allows continuous, computerized updates, significantly reducing the window of exposure. The system must validate the fixes to confirm the vulnerability was actually resolved, closing the remediation loop.

Bridge the Gap to Remediation

Monitoring generates data, but it is useless without corresponding action. To automate the handoff from discovery to mitigation, integrate monitoring alerts into existing workflows, such as Jira, ServiceNow, or Splunk. This integration makes sure that alerts reach the appropriate remediation teams immediately, turning visibility into protective action.

FAQs about attack surface monitoring

How is ASM different from vulnerability scanning?

Vulnerability scanning involves an authenticated, internal scan against known assets to find security flaws. ASM, however, is an unauthenticated, external process that first discovers all external assets (including unknown shadow IT) and then assesses them from an attacker's perspective.

For a detailed comparison, read our guide on attack surface monitoring versus vulnerability management. 

Is ASM the same as continuous penetration testing?

Penetration testing is a time-boxed, goal-oriented security assessment performed by human experts. ASM is an automated, continuous, and broader process focused on constant asset discovery and identifying all external vulnerabilities. It supports penetration testing by providing the initial list of exposed assets.

Can ASM integrate with third-party risk solutions?

Modern ASM can integrate with Third-Party Risk Management (TPRM) platforms to extend monitoring to the exposed assets of essential vendors, providing a complete view of digital supply chain risk.

Securing the future of your organization

UpGuard’s Attack Surface Management supports organizations in transitioning to a proactive and resilient cybersecurity strategy.

UpGuard’s capabilities include:

• Continuous monitoring: It continually scans the internet to identify and link IP addresses and domains using DNS, certificates, and web archives, helping to discover previously unknown assets, such as test servers or subdomains, as they are created.
• Real-time visibility: The platform provides up-to-date security posture snapshots, enabling quick detection of new assets or exposed APIs.
• Attacker’s view: It provides an external view of your security posture, revealing vulnerabilities and misconfigurations that a hacker might spot.
• Risk reduction: It helps simplify your attack surface by flagging "unmaintained page" risks (such as stale DNS records), allowing for the decommissioning of abandoned assets.
• Prioritization: Risks are automatically prioritized by severity, enabling your teams to focus on high-impact remediations.

Download our ebook to learn how Attack Surface Management helps you monitor and secure your most critical data and assets.

‍