Platform · Discover
External attack surface management
An attacker starts on the outside with a domain name and works inward until they find something you left exposed. External attack surface management is about doing that first, so you see your own exposure the way an outsider sees it.
The concept
External attack surface management, shortened to EASM, is the ongoing work of finding and watching everything an organization exposes to the public internet, seen the way an outsider would see it. Gartner named the category in 2021 to describe tools that discover and inventory internet-facing assets a company may not even realize it owns. EASM begins on the outside, with no list to start from, and works inward, mapping the domains, hosts, services, and certificates an attacker doing reconnaissance would run into first.
In the exposure management loop, this is the discovery stage, and it feeds everything after it. Prioritization and validation only work on assets that have been found. A flaw on a server nobody cataloged will not get fixed, because nobody knows it is there. The rest of a security program depends on having that full inventory.
Where the industry falls short
Most security programs still begin on the inside, with a list of assets the organization already keeps. A traditional vulnerability scanner checks the things on that list, which means anything absent from it sits outside the program entirely. The list is hard to keep accurate. Cloud accounts come and go, a team stands up a subdomain without telling anyone, an acquisition arrives with servers no one has audited, and a service spun up years ago is quietly still running. Each of those is an asset facing the internet that no one is watching.
Attackers have moved toward exactly this gap. Verizon's 2025 Data Breach Investigations Report found that exploiting a vulnerability to break in rose 34 percent in a single year, on top of a 180 percent jump the year before, and it now sits behind about 20 percent of breaches. A large share of that pressure lands on internet-facing edge equipment such as firewalls and remote-access gateways, where the same report measured how quickly a newly disclosed critical flaw reached mass exploitation and found the median to be zero days.
The Verskop difference
Mapped from the outside, with an honest count.
Verskop begins where an attacker would and enumerates the internet-facing assets an outsider can reach, without ever touching anything it should not.
From a single domain, Verskop maps what you expose from the outside. The blue marks are assets you already know about. The amber ones are assets it surfaced that you did not know you had.
What an outsider can reach
From a single domain, Verskop resolves the subdomains and live hosts behind it, notes the ports and the services listening on them, reads certificate and TLS posture, and fingerprints the technology running on each service. The work stays on the outside, looking only at what any stranger on the internet could already see, so it needs no permission to run and nothing on your side is disturbed.
- Subdomain and host discovery from a single starting domain
- Ports, services, and cleartext exposure noted from the outside
- Certificate and TLS posture read on every host
- Per-host technology fingerprinting, with the version pinned down where the evidence shows it
An asset count that reflects reality
Loose discovery tends to inflate the numbers. A wildcard DNS record can make one host look like a thousand, and the same server often answers to several aliases. Verskop collapses that noise, so the count in the report reflects what is genuinely out there and holds up when someone checks it.
- Wildcard and alias noise removed before anything is counted
- Duplicate hosts collapsed to the single asset behind them
The surface changes, so monitoring is continuous
Your internet-facing exposure shifts week to week. Because discovery looks only at public information, Verskop can repeat it on a schedule and flag a newly exposed service, a freshly opened port, or a certificate about to expire as soon as it appears. New exposure gets caught while there is still time to close it.
- Re-scans run on a schedule, with changes flagged
- New exposure surfaced as it appears, while there is still time to act
The standards this rests on
Every figure above is sourced. The only claim that is ours is what Rampart Cybersecurity LLC and Verskop do.
See it on your domain
See what you expose from the outside in.
Point Verskop at your primary domain and we will show you what discovery turns up, including the assets you may not know you own.