What is EASM?
External Attack Surface Management (EASM) is a continuous, attacker's-eye-view inventory of every internet-facing asset that belongs to your organisation — subdomains, exposed services, open ports, third-party dependencies, leaked credentials, lookalike domains, expired SSL certificates, and forgotten cloud assets. Unlike traditional vulnerability scanning, EASM operates from the public internet without any internal access, surfacing shadow IT and supply-chain exposures that internal tools miss.
EASM platforms (Infilux's own GuardEon, plus Bitsight, Censys, CyCognito, SocRadar) operate by combining DNS enumeration, certificate-transparency monitoring, port and service fingerprinting, dark-web crawling, and brand-impersonation detection. The goal is to know what an attacker reconning your organisation would discover before they discover it.
Where traditional vulnerability management is inward-looking — agents on your servers, scans of CIDR ranges you provide — EASM is outward-looking. It finds the dev subdomain a contractor stood up two years ago, the AWS S3 bucket your subsidiary forgot to lock down, the API endpoint that returned to public after a misconfigured load-balancer change, and the typosquat domain registered by a phishing crew last week.
Risk scoring in EASM is dynamic. Each finding gets a continuously-updated criticality score based on exploitability (known CVE? public PoC?), exposure (anonymously reachable? authentication-gated?), and business impact (production user data? payment flows?). Most platforms integrate with ticketing (Jira, ServiceNow) to route findings to the responsible engineering team.
Key points
- Continuous, outside-in asset discovery (no internal agents).
- Surfaces shadow IT, forgotten cloud assets, supply-chain exposures.
- Combines DNS, cert transparency, dark web, port/service fingerprinting, brand monitoring.
- Real-time risk scoring with ticketing integration (Jira, ServiceNow, Slack).
- Required for mature programmes under NIST CSF 2.0 ID.AM-2 and CIS Control 1.