See what attackers see.
Scan it first.
Manual security scans of your internet-facing assets, run from the outside. 12,000+ focused checks, no agent, free to start.
Outside-in,
on your schedule.
You pick the asset and the moment. S4E runs the checks from the internet and gives you findings you can act on.
From the outside
No agent, no server login
Free to start
Pick the depth you need.
Every mode runs on the same engine, so a quick check and a deep scan speak the same language.
Full Scan
Light Scan
Crawl Only
Single Scan
A library of 12,000+ focused, single-purpose scans targeting specific CVEs, technologies, and configuration weaknesses. Every feature on this page is powered by this engine.
New CVEs, covered
within hours.
S4E monitors the global vulnerability landscape daily and ships scanner support as new CVEs emerge so your assets are checked before attackers can exploit them.
See all CVE scanners →Security intel,
always one tab away.
Install the S4E extension and scan from the tab you're already on. Save your session for authenticated web scans, collect attack surface as you browse, and set crawl include/exclude rules without leaving the page.
Add to Chrome Free →Keep it running,
or look inside.
AI-based CTEM
S4E keeps watching: continuous scanning, prioritised actions and AI fix guidance.
Credentialed Scanning
Add a server login and S4E also looks inside the server for outdated, vulnerable software.
Start free.
Scale when ready.
No credit card. No commitment. Just sign up and scan.