As the digital perimeter continues to dissolve, security leaders are rethinking how they manage cyber risk. Penetration testing and vulnerability management remain essential—but they’re no longer enough on their own. Today’s attackers exploit what lies beyond your defined scope: misconfigured cloud buckets, forgotten subdomains, exposed APIs, and rogue SaaS apps.
To stay ahead, organizations need not just testing, but visibility. That’s where continuous Attack Surface Management (ASM) comes in.
Penetration testing: critical for validation
Penetration testing plays a crucial role in any mature cybersecurity program. It simulates real-world attacks to validate defensive controls, assess the potential impact of breaches, and expose weaknesses that automated tools might miss. Penetration tests are also key for demonstrating compliance, stress-testing incident response protocols, and identifying high-impact vulnerabilities in known environments.
But these tests are, by design, point-in-time. They are scoped engagements that reflect the conditions of your environment during a specific window. If an unknown asset spins up the day after your test concludes, no one is watching—except your adversaries.
Penetration tests are critical not just for uncovering overlooked vulnerabilities, but also for validating how an organization would respond in a breach scenario. As DomainGuard cofounder Erkin Djindjiev often emphasizes, they show how real-world threat actors could exploit those gaps—not just that the gaps exist.
ASM: your continuous line of sight
Attack Surface Management is the continuous process of discovering, monitoring, and assessing internet-facing assets—including domains, subdomains, APIs, cloud storage, VPN portals, and more. It captures not just the known, but the unknown and unmanaged components of your digital footprint.
ASM helps you:
- Detect new or unexpected assets in near real time
- Uncover exposures created by misconfigurations or third-party vendors
- Reduce your visible footprint
- Support incident response and vulnerability triage
ASM fills the gap between reactive scanning and high-effort testing. Vulnerability management uncovers what’s already known. Penetration testing reveals what could go wrong. But ASM exposes the assets and exposures no one saw coming—often before attackers do.
Why you need both
Penetration testing and ASM are not redundant. In fact, they work best together:
- Together, they reduce blind spots. ASM operates continuously between pen test intervals, ensuring you maintain visibility as your environment evolves.
- ASM enhances your pen test scope. If ASM uncovers a previously unknown domain, system, or service, it can be included in your next testing schedule.
- Validation of ASM findings. A newly discovered exposure may not be obviously exploitable, but continuous testing simulates attacker behavior to find out.
We’ve seen customers maintain annual penetration testing schedules, complemented by ongoing ASM. By continuously validating and addressing exploitable issues between scheduled tests, they are turning visibility into real protection.
Building a program that works
Getting started with ASM doesn’t require a major investment upfront. Begin by:
- Running baseline discovery using open-source tools (e.g., Amass, Shodan, Nuclei)
- Comparing externally discovered assets to internal inventories or CMDBs
- Feeding unknown or unmanaged assets into your vulnerability scanning and penetration testing workflows
- Establishing a repeatable process for triage, asset ownership, and remediation
Over time, this process can be automated and integrated with platforms that offer continuous monitoring, ticketing, and reporting. ASM not only enhances your penetration testing and vulnerability management programs but also strengthens audit readiness and supports compliance with standards such as CIS, PCI DSS, and ISO 27001.
Final thought: visibility and validation go hand in hand
There is no silver bullet in cybersecurity—only layered strategies. Penetration testing remains indispensable, but it thrives when complemented by continuous visibility into your attack surface. ASM offers proactive insight to discover what you didn’t know existed. Continuous testing shows you what could go wrong if you don’t act.
You need both discovery and validation to stay ahead. ASM provides early visibility into exposures, but without validation—whether through internal testing or an external partner—there’s no way to confirm the true risk. Combined, these efforts help organizations move from reactive remediation to proactive protection. And in today’s threat environment, that’s the visibility every executive needs to protect their company.
