Attack Surface Management, or ASM, is quickly becoming a core part of modern cybersecurity strategies. Why? Because most security teams today have a visibility problem.
From forgotten cloud instances to abandoned subdomains, exposed APIs, shadow IT and employee-owned SaaS tools, your organization’s external attack surface is growing fast, whether you realize it or not.
Attackers are constantly scanning the internet for these blind spots. ASM helps you find them first.
Let’s break it down.
What is an attack surface?
Your attack surface is the sum of all internet-facing assets an attacker could potentially exploit to gain unauthorized access to your systems.
That includes:
Websites, subdomains, web apps
Cloud environments (AWS, Azure, GCP)
Public-facing APIs and ports
Remote login services (RDP, VPN, SSH)
Misconfigured DNS entries
Forgotten test environments or staging servers
Employee-owned tools and SaaS apps
In short: anything that can be found and targeted from the outside.
And unlike your internal infrastructure, these assets are exposed 24/7.
So what is ASM (Attack Surface Management)?
Attack Surface Management (ASM) is the continuous process of discovering, monitoring, and managing all external assets connected to your organization — so you can identify and fix risks before attackers exploit them.
The three main pillars of ASM are:
Discovery
Automatically detect known and unknown internet-facing assets, including shadow IT, forgotten domains, and third-party exposures.
Monitoring
Continuously track your assets for changes, misconfigurations, vulnerabilities, and signs of exposure.
Remediation
Prioritize and fix issues based on risk — from unpatched software to exposed databases or leaked credentials.
Think of ASM as an always-on security radar for your digital footprint.
Why is ASM important?
Attackers don’t care what’s meant to be public. They exploit what is public.
That’s why ASM is so valuable. It:
Helps you see what attackers see
Reduces your exposure to external threats
Improves incident response and breach prevention
Complements your existing tools like SIEM, vulnerability scanners, or firewalls
Gives you a clear inventory of your digital perimeter
Without ASM, your organization is effectively blind to a huge portion of its risk.
While ASM focuses on external assets, Cloud Security Posture Management (CSPM) focuses on cloud configuration and compliance within platforms like AWS or Azure.
Many organizations benefit from using both — to cover different layers of their security posture.
Who needs ASM?
If your organization uses the internet (and we’re guessing it does), you need some form of ASM.
It’s especially important if:
You’re growing fast and adding new tools or domains regularly
You work in a regulated industry or handle sensitive data
You’ve recently migrated to the cloud
You’re managing multiple subsidiaries or business units
You don’t have a clear inventory of all public-facing assets
Even small businesses can benefit — and many attackers specifically target smaller companies because they tend to have weaker defenses.
Do I need a tool for ASM?
Technically, you could try to do it manually. But keeping track of every public asset, third-party risk, and misconfiguration, across teams and regions, is nearly impossible without the right tooling.
A good ASM platform helps you:
Continuously discover assets (even ones you didn’t know existed)
Detect risks in real time
Alert the right people automatically
Track improvements and exposure over time
Closing thoughts
Managing your attack surface doesn’t have to be complex or expensive.
The key is to start small, stay consistent, and use tools that work with your workflow, not against it.
That’s exactly why we built Tresal.
Want to see what your attack surface looks like today?
You might be surprised.