What is an Attack Surface? Definition & Management for Business Security

What is an Attack Surface in Cybersecurity?

An attack surface is the complete set of all possible entry points where cyber criminals or unauthorized users can attempt to exploit vulnerabilities to breach your company systems, networks or data. According to the National Institute of Standards and Technology (NIST), it includes all hardware, software, network services, human elements and physical components that can be targeted by threat actors. Every business, regardless of size, has an attack surface that requires continuous monitoring and management to reduce security risks.

Attack Surface Definition & Key Components

An attack surface encompasses the sum total of all vulnerabilities in your computing environment that are accessible to attackers. This includes network vulnerabilities, software vulnerabilities and human vulnerabilities that could be exploited to gain unauthorized access, disrupt operations or steal sensitive information. Understanding and managing your attack surface is fundamental to implementing effective cybersecurity defenses.

Types of Attack Surfaces

Digital Attack Surface

• Applications & Services: Web applications, APIs, email services, cloud services, SaaS platforms
• Network Infrastructure: Firewalls, routers, switches, VPNs, WiFi networks, DNS servers
• Endpoints: Workstations, laptops, mobile devices, IoT devices, servers, virtual machines
• Data Storage: Databases, file servers, cloud storage, physical storage media, backups

Physical Attack Surface

• Facilities: Server rooms, office spaces, reception areas, data centers
• Hardware: Physical access to computers, network equipment, storage devices, servers
• Documentation: Printed materials, disposed documents containing sensitive information

Human Attack Surface

• Employees: Vulnerability to social engineering, phishing attempts, impersonation attacks
• Credentials: Usernames, passwords, access cards, biometric access, MFA tokens
• Privileges: Administrative rights, access levels, user permissions, service accounts

“Attack surface vulnerabilities are the primary entry points for ransomware attacks and most successful breaches exploit known vulnerabilities that could have been remediated!”

– The Commodore, DarkSub

Key Points for SMBs, Business Owners and IT Managers

Business Impact

• Every new technology, service or user added to your environment expands your attack surface
• 60% of SMBs go out of business within six months of a major security breach
• Attack surface vulnerabilities are the primary entry points for ransomware attacks
• Most successful breaches exploit known vulnerabilities that could have been remediated
• The average cost of a data breach for small businesses exceeds $108,000 per incident

Essential Actions

1. Conduct Regular Attack Surface Mapping: Document all assets, connections and potential entry points
2. Implement Access Controls: Apply least privilege principles to minimize unnecessary exposure
3. Maintain Patching Schedules: Prioritize updates for internet-facing systems
4. Decommission Unused Systems: Remove or disable unused applications, services and accounts
5. Segment Networks: Isolate critical systems from general-purpose networks

Cost-Effective Management Strategies

• Focus on securing the most critical business systems first
• Implement basic network monitoring to detect unusual activity
• Use cloud security services that automatically update protections
• Establish clear BYOD (Bring Your Own Device) policies
• Reduce unnecessary external connections and third-party integrations

Key Points for Digital Agencies and Cyber Advisors

Client Guidance Framework

1. Assessment Methodology: Develop a standard approach to map client attack surfaces
2. Risk Prioritization: Help clients distinguish between theoretical and practical risks
3. Remediation Roadmaps: Create phased plans based on business impact and implementation cost
4. Communication Strategy: Translate technical vulnerabilities into business risk language

Advanced Considerations

• Incorporate attack surface management (ASM) into DevOps workflows
• Implement continuous discovery and monitoring of shadow IT
• Consider API security as a distinct attack surface component
• Evaluate supply chain dependencies as extended attack surface elements
• Develop metrics to demonstrate attack surface reduction over time

Why Attack Surface Management Matters

Effective attack surface management is crucial because businesses cannot secure what they don't know exists. By identifying, classifying and securing all potential entry points, your company can significantly reduce risk of compromise. This proactive approach helps prevent data breaches, maintain business continuity and protect customer trust.