5 Core Functions of Attack Surface Management

5 Core Functions of Attack Surface Management

Effective attack surface management (ASM) performs five key functions to combat vulnerabilities and minimize risks of cyberattacks and data breaches.

If you made it through 2022 without experiencing a major cyberattack that compromised sensitive data, consider yourself lucky – yet that does not mean you should relax.


Attack surface management provides visibility to identify and prioritize vulnerabilities, helping prevent cyberattacks and data breaches. For the process to be successful, five core functions must be included within it:

Discovery involves the identification of all known systems, both those not connected to an organization’s network and remote access points, that exist within their digital supply chain as well as third party and IoT devices. It should be an ongoing process.

An inventory of all internet-facing assets allows identifying and mapping entry points, then prioritizing remediation efforts accordingly.

At this phase, potential vulnerabilities and misconfigurations are assessed, risks ranked and remediation steps presented to the security operations team. All this information is then tied back to an organization’s risk profile, compliance requirements and business goals; thus allowing SOC staff to prioritize efforts and make more informed decisions regarding vulnerability remediation.

Today’s organizations face many more security risks than just those related to firewalled on-premises systems; today’s organizations often feature unmanaged devices, cloud resources, IoT devices, and SaaS applications that make identifying their full attack surface challenging.

Attackers take full advantage of this dynamic environment to create vulnerabilities within an organization, necessitating organizations to frequently adapt their attack surface management program – including the deployment and testing of continuous monitoring solutions that detect issues immediately and can address them effectively.

Ideal, these functions should be automated so that the SOC can focus on other priorities while staying one step ahead of attackers and lowering its risk for cyberattacks and data breaches. Complying with industry regulations and internal policies is also key for organizations, so using an attack surface management solution like IONIX Connective Intelligence to address these challenges enables businesses to do more with limited resources in less time. Download a free trial of Tenable’s Attack Surface Management Software today and see for yourself! 2023 Tenable, Inc. All rights are reserved by Tenable Inc. Tenable, Nessus, Lumin and Assure are trademarks registered by Tenable in various countries around the world; other marks belong solely to their respective owners.


An accurate assessment of an organization’s external attack surface is key to mitigating cyber risks. The initial step in attack surface management involves identifying and mapping all assets accessible over the internet from outside-in, including internal systems, cloud services, third-party software and remote access protocols – this data helps assess vulnerability landscape and prioritize risk remediation efforts.

Traditional asset inventories were performed manually and only occasionally. Due to modern infrastructure’s rapid evolution and new cloud instances created through M&A transactions or digital transformation initiatives, however, security teams cannot keep pace with all these changes manually; moreover, their quality has an immediate effect on all security processes.

An attack surface management solution equipped with advanced threat intelligence solutions designed to emulate attacker tools can detect unknown, rogue or external assets that serve as entryways for cyberattackers and expose organizations to unnecessary risk. By using contextual data from threat intelligence platforms to prioritize risks according to risk-based prioritization criteria, information security and IT teams can focus on eliminating their most significant vulnerabilities first.

As part of an organization’s inventory phase, it’s also vital that all its internet-facing assets are identified and understood. This helps prevent future incidents by eliminating false positives caused by traditional scanners; also important is understanding the business impact and vulnerability associated with an asset; for instance when workloads are exposed over the internet they could expose sensitive data or provide hackers with entry points into corporate networks.

An attack surface management solution with contextual data can also help avoid alert fatigue, which results in security teams being overwhelmed with alarms that go unanswered and ultimately slow down security response times. Quick identification of what vulnerabilities most threaten the business so security, IT, and DevSecOps teams can act accordingly is essential.

Threat Prioritization

Attack surface management involves more than simply discovering and mapping entry points into a network; it also involves evaluating vulnerabilities and prioritizing them for risk mitigation and remediation, without bombarding infosec/DevSecOps teams with irrelevant alerts. This process takes place during threat prioritization phase of attack surface management.

Prioritization of threats and vulnerabilities involves ranking them according to impact, exploitability, and likelihood of discovery. This helps security and DevOps teams focus on the most urgent vulnerabilities. Considering context when prioritizing vulnerabilities is also an integral component – considering potential effects on core business functions, regulatory compliance obligations, reputation or brand value may all influence severity levels for specific vulnerabilities.

Additionally, it is vitally important to take into account the ripple effects of vulnerabilities across an ecosystem. A vulnerability in one cloud service could spread to multiple other services and cause data theft or business impacts that result in sensitive information being lost or other negative repercussions. Furthermore, taking into account asset complexity, usage patterns and breach implications is vitally important.

Security and DevOps teams should take an in-depth analysis of asset relationships during this phase, in order to better identify how one compromised asset could potentially impact other systems and data within an organization, as well as which department is accountable for the affected system. This is an integral component of reducing human error – which remains one of the primary causes of cybersecurity breaches.

An effective attack surface management framework will evaluate and score each asset within a particular environment to provide a holistic and objective measure of an organization’s security status that can be compared with others in its industry, geographic location or sector.

Continuous Attack Surface Management (CASM) is an ongoing process that monitors an organization’s internal and external attack surfaces for suspicious activities that could compromise vulnerable systems quickly, in order to quickly detect threats to cyber defenses. CASM helps organizations keep an eye on a digital landscape that constantly evolves and shifts.


Attack surfaces refer to vulnerabilities, misconfigurations and weaknesses which a threat actor can exploit in order to gain entry into a system or network without authorization. The more entry points there are, the higher is its risk.

An effective attack surface management program seeks to identify and reduce the number of vulnerabilities that attackers can exploit to break in, providing regular scanning cycles and the identification of assets added or modified since previous scanning cycles.

Known digital assets are devices and systems known to security teams and authorized for connection to their networks. During inventory phase, known digital assets and associated vulnerabilities are revealed; once this list of vulnerable assets has been identified, the security team can assess them accordingly and prioritize remediation efforts accordingly.

Mitigation seeks to limit or remove access paths leading to sensitive information such as personally identifiable or financial data, which includes PHI/PCI as well as customer and financial details. Zero-trust policies are one way of doing this, restricting network traffic only to systems and applications which need it.

One alternative approach is implementing a continuous attack surface management (ASM) solution that monitors both internal and external Internet-facing environments for new assets, vulnerabilities, or other threats that arise. An ASM tool should perform regular scans that identify assets and vulnerabilities so security teams can detect threats early.

Additionally to ASM discovery, assessment, and prioritization processes, solutions should allow the SOC to conduct regular remediation activities while tracking their impact on cyber risk within an organization – giving visibility into its worth for senior leadership.

Today’s expansive digital landscape can present even the most experienced security teams with an uphill struggle. Work-from-home trends, COVID-19 legislation and cloud migration have dramatically expanded the number of external-facing assets and vulnerabilities they must protect, while many legacy tools lack context that is key for prioritizing remediation efforts. A unified Asset Service Management platform that automatically discovers and assesses all assets on-premise or cloud provides security teams with valuable insight needed to identify blind spots and reduce cyber exposure risk for their organization.

Mark Funk
Mark Funk is an experienced information security specialist who works with enterprises to mature and improve their enterprise security programs. Previously, he worked as a security news reporter.