We could reminisce about the good old (and simpler) times in enterprise IT, and it would do us little good. The perimeter is everywhere nowadays, from the latest promotional sites to seemingly endless third-party SaaS tools spinning up on a company’s dime. As cloud infrastructure scales dynamically and remote work stays for good, the attack surface slowly but surely turns into a sprawling archipelago of endpoints.
Arguably the worst thing in all of this is that security teams don’t know what they own, courtesy of shadow IT (more on this particular problem below). When you can’t defend what you can’t see, attack surface management (ASM) becomes paramount.
Why managing an attack surface is a nightmare
The theory is sound: continuous outside-in visibility defends an organization by providing insight into all potential digital and physical endpoints, which makes it possible to identify and mitigate risks. Applying it in the real world is an entirely different story because of these challenges:
- Explosion of shadow IT: Unsanctioned apps, forgotten subdomains, legacy services, unauthorized devices, and shadow AI (as the cherry on top) are just some examples of hardware and software used without IT's explicit approval or oversight. Then, there are non-IT teams that try to be agile and adopt new cloud tools or launch customer-facing portals without notifying security. Doing so leaves behind an unmonitored trail that is routinely strewn with default admin passwords and unpatched libraries.
- Shifting attack surface: Relying on quarterly vulnerability scans or static inventory spreadsheets is no good when attack surfaces are changing at a frightening pace. By the time a manual audit is completed, various updates, architectural coding flaws, reconfigurations, third-party supply chain dependencies, or excessive user permissions can create new vulnerabilities with ease.
- Alert fatigue: Vulnerability scanners of the legacy variety almost universally flood security teams with countless CVSS (Common Vulnerability Scoring System) alerts. The problem is that many of these flagged vulnerabilities exist on isolated, internal-only servers or behind web application firewalls (WAFs) where they’re out of reach. So, when you spend (better yet, waste) hours sifting through a lot of noise, true external risks tend to go unnoticed.
- Fragmented tools and poor overall visibility: Traditional security architectures have a silo problem, where they rely on one tool for cloud monitoring, a separate scanner for web applications, another platform entirely for something else, and so on. Hence, numerous blind spots emerge as a natural byproduct, neatly hiding critical exposures, which threat actors just love.
How ASM works
At the center is a continuous, automated workflow that follows a four-step operational blueprint:
1. Continuous asset and perimeter mapping
ASM tools combine deep DNS enumeration, SSL/TLS certificate parsing, WHOIS crawling, and public IP ranges to come up with a full map of a company’s digital footprint. They automatically link root domains to exposed cloud storage buckets, open ports, API endpoints, and unvetted AI models, among other things, essentially placing one big 1000W floodlight on shadow IT.
2. Active vulnerability verification
This is perhaps where legacy tools are most fallible. They read software version tags from HTTP headers to extract software name and version numbers, also known as banner grabbing. For the most part, these tools assume a vulnerability is there. But, they can’t figure out if a patch or a vendor-backported fix has already been applied to that version, which leads to false positives.
Advanced ASM platforms like NordStellar use active testing, specifically dynamic application security testing (DAST), to interact with a vulnerability from the open internet just like an external attacker would. They also add safe exploit simulations in the mix to confirm whether a vulnerability (be it a garden-variety SQL injection, remote code execution, etc.) is actually exploitable, so as not to consume analysts’ time.
3. Risk prioritization
Not so long ago, security teams had to wade through hundreds of CVSS scores to prioritize immediate patching and risk mitigation. And while using a numerical scale certainly simplifies the task at hand, the entire process lacks the full picture view.
Through cross-references of verified exploitability with business context, the ASM platform can spot a critical flaw on a, say, staging server exposing sensitive customer data. At the same time, an unexploitable vulnerability on an isolated system gets de-prioritized.
4. Actionable remediation
Finding a hole in your defense is only half the battle. The other half is closing it as fast as possible to prevent a breach. ASM tools convert validated threats into prioritized work items, delivering detailed evidence and step-by-step remedy instructions directly to IT and engineering teams so they can do their magic before any real damage occurs.
How ASM improves your company’s defense posture
Implementing attack surface management fundamentally changes how your security team operates day-to-day, most notably in these areas:
- Gets rid of shadow IT blind spots: Continuous crawling sees to it that whenever there’s a new element in the workflow, it gets cataloged and evaluated within minutes. That way, there are no unmonitored blind spots for threat actors to discover.
- Eliminates false positives: Active verification of vulnerabilities through safe exploit simulations filters out noise that is oftentimes largely theoretical. As a result, your analysts stop chasing ghosts and divert their efforts to fixing confirmed entry points.
- Catches errors automatically: The role of human error in data breaches is well documented, since a large percentage of incidents doesn’t involve fancy zero-day exploits. Whether someone forgot to renew an SSL certificate or left default credentials active on a router, ASM catches these slipups right away.
- Reduces triage time: Thanks to pre-verified, prioritized risk data, SecOps teams can focus on strategic hardening rather than manual data entry and raw scanner notifications.
- Tailors monitoring: ASM scanning is customizable, so you can adapt it to your needs. It allows you to run targeted checks across specific IP ranges or domain groups on demand whenever you need fresh data for incident response, audits, post-deployment validation, and such.
- Accelerates remediation: ASM platforms generate evidence-backed remediation guides that feature plenty of context for developer teams. They receive precise reproduction steps and code-level recommendations, shrinking mean-time-to-remediate (MTTR) from days to hours.
- Improves regulatory compliance: External visibility directly meets key requirements in modern standards like the NIS 2 Directive, DORA, and SOC 2 that explicitly mandate continuous asset discovery and risk-based vulnerability management.
In a nutshell, attack surface management flips the advantage back to you, so you can lock the doors before the attacker reaches for the handle.