Attack Surface Management (ASM)

Overview

Attack Surface Management (ASM) is the continuous discovery, classification, prioritization, and reduction of assets, exposures, identities, dependencies, and pathways that an attacker could use. The control exists to reduce the likelihood and impact of compromise by making assets, identities, software, data, exposures, and control responsibilities visible and governable. ASM can include internal and external exposure, while External Attack Surface Management focuses specifically on assets observable or reachable from outside the organization. It should be interpreted alongside External Attack Surface Management (EASM) because the concepts can affect the same decision without representing the same control, event, or risk.

The workflow identifies the protected object and owner, evaluates threats and dependencies, applies preventive and detective safeguards, and routes exceptions or failures to accountable teams. Controls should be tested against realistic misuse, version changes, privileged access, third parties, and recovery conditions. In this context, the program should combine automated discovery with ownership validation, business criticality, exploitability, control coverage, remediation workflow, exception handling, and confirmation that exposures are actually removed.

It should connect the term to Asset Inventory where that relationship changes access, transaction treatment, investigation, communication, or recovery.

Records should preserve scope, ownership, configuration or policy version, changes, approvals, test results, alerts, exceptions, incidents, remediation, and verification that the risk was reduced. Evidence must be protected from alteration and retained according to legal and operational need.

Useful measures include coverage, control effectiveness, unresolved critical findings, remediation age, unauthorized changes, detection time, incident frequency, repeat weaknesses, exception volume, and recovery performance.

The relationship with API Inventory should be documented where it affects residual risk or control ownership.