Key takeaways
ASM Is no longer optional. The number of entry points into your organization is infinite. Cloud infrastructure, SaaS apps, mobile devices, hybrid work, and third-party vendors have all contributed to a sprawling and often invisible digital footprint — what’s known as the attack surface.
That expansion isn’t slowing down. On average, 100+ new vulnerabilities emerge every day, creating an overwhelming burden on already stretched security teams. And those are the vulnerabilities we know about!
This is where attack surface management (ASM) comes in.
Attack Surface Management (ASM) is the continuous process of discovering, monitoring, evaluating, and reducing all the exposure points across your digital ecosystem. The goal is simple: make the attack surface visible and manageable, so attackers don’t find the gaps before you do.
ASM helps answer questions like:
ASM gives security teams the context and control needed to proactively manage risk, and not just respond after the fact. With threat actors exploiting weaknesses faster than ever, ASM helps shift organizations toward a more resilient, prevention-first security posture.
An attack surface is the sum total of all possible ways an attacker could gain access to your environment, whether through exposed infrastructure, human error, unmonitored third-party tools, or forgotten test servers.
It includes every internet-facing asset, every internal system or endpoint, every third-party integration, every single human entry point. In short: your attack surface is not only about technology, it’s about anything that could be exploited to compromise your business.
see primer on what constitutes an attack surface: What Is an Attack Surface?
An attack surface is what’s exposed. An attack vector is how it’s attacked. ASM focuses on reducing exposed assets, thereby limiting attacker options.
Every year, organizations grow more connected — and more exposed. According to recent industry reports:
With digital infrastructure evolving faster than security practices, it’s easy to lose visibility over what’s live, what’s vulnerable, and what’s connected. ASM helps close that visibility gap.
Without ASM, most organizations are flying blind across parts of their infrastructure, leaving shadow assets and outdated systems exposed to increasingly automated and opportunistic attackers.
ASM isn’t a one-time scan or an annual audit. It’s a continuous lifecycle designed to help organizations stay ahead of risk. Your ASM program can be custom to your organization, and should include these four key stages:
Step one is to understand all your assets. Inventory all internet-facing and internal assets, including:
Example: A development team spins up a temporary cloud environment that gets indexed by search engines. Discovery ensures it gets flagged, even if IT wasn’t informed. That cloud environment expands the attack surface.
Not all risks are equal. Group and prioritize assets based on business context and risk. Knowing what something is, and how critical it is to operations, helps guide your response. Prioritize assets based on:
Fix what poses the greatest risk first. Consider risk scoring to assist in prioritization and know your organization’s risk tolerance and risk appetite.
Example: An exposed staging environment may be low priority in terms of attack service risk. In contrast, an exposed production database with customer data is not.
Now it’s time to take action. Act on exposures, as prioritized, by patching, removing, isolating, or hardening assets. Actions here will depend on the prioritized assets but common remediation can include:
After remediating, always be sure to validate that your actions actually worked — do not assume.
Example: A SOC uses ASM data in its SOAR playbook to automatically quarantine risky assets and assign tickets to relevant teams.
Use automation to continuously monitor and track changes continuously and over time. The continuous monitoring is essential because your attack surface changes constantly: new assets get added, apps get misconfigured, people leave the organization. ASM keeps your inventory fresh and your alerts real.
Watch for changes and exposures, such as:
ASM isn’t limited to firewalls and endpoints. That’s why assets in scope for ASM must include:
Even with the right intent, managing attack surfaces can be difficult to implement without the right strategy or tooling. Common roadblocks include:
Attack surfaces may be expanding, but so are the tools and strategies to manage them. With attacks on organizations happening every day, we can no longer rely on manual processes alone.
Platforms like Splunk help teams automate discovery, correlate data across assets, and respond faster, making attack surface management both manageable and actionable. Splunk brings structure and visibility to ASM by helping teams:
Attack surface management (ASM) is asset-centric and focuses on discovering all assets and exposures, known or unknown, across your environment. Vulnerability management is software-centric, identifying and remediating flaws (like CVEs) in systems already inventoried. ASM and vulnerability management are complementary: ASM helps you find what needs protection, while vulnerability management helps you fix known issues.
No. ASM includes both external and internal assets, covering cloud infrastructure, on-premises environments, shadow IT, and even human touchpoints.
ASM should be continuous. Because your environment changes daily, continuous monitoring ensures your asset inventory and risk visibility stay current.
Choose tools that automatically discover assets (cloud, web, third-party), continuously monitor exposure changes, risk-score assets by exploitability, integrate with SIEM/SOAR/ticketing systems, scale across hybrid environments, and offer flexible alerting and reporting.
Yes. ASM continuously verifies the existence and status of assets, supporting least-privilege access and helping enforce Zero Trust security principles.
No. ASM complements vulnerability scanning by ensuring all assets—known and unknown—are discovered. Vulnerability scanning then focuses on finding software-level issues within those assets.
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This posting does not necessarily represent Splunk's position, strategies or opinion.
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