Minimizing Your Organization's Attack Surface: A Comprehensive Guide

In today's digital world, organizations large and small rely heavily on online systems and infrastructure to run their operations. However, this increased dependence on technology also expands an organization's digital footprint and exposes more potential vulnerabilities that cyber attackers can exploit. This digital footprint, known as an organization's attack surface, encompasses everything from public-facing websites and servers to employee endpoints and cloud services. As attack surfaces continue growing, security teams are finding it increasingly difficult to maintain adequate visibility and control across their environments.

According to some estimates, the global average enterprise attack surface contains over 2,000 externally visible assets. Without proper governance, this number tends to expand rapidly as companies undergo digital transformation initiatives and adopt new technologies. More assets and more connections also introduce more potential vulnerabilities that attackers can take advantage of. Verizon's 2021 Data Breach Investigations Report revealed that external attacks are now the primary source of security incidents, accounting for 85% of breaches analyzed. As threats grow more sophisticated and attacks become more targeted, minimizing the attack surface must become a strategic imperative for organizations that value their data security.

In this comprehensive guide, we will explore what an attack surface is, how it is expanding, and most importantly - how organizations can reduce their exposure through continuous discovery, monitoring, and remediation across their environments.

What is an Attack Surface?

In cybersecurity, the term "attack surface" refers to the total sum of points where an unauthorized user or attacker can try to enter, access, or extract data from an environment. It encompasses all exposed vulnerabilities and weak points across an organization's people, processes, and technology that could potentially be exploited to cause harm.

Some elements that comprise an attack surface include:

• Network Infrastructure - Servers, endpoints, mobile devices, network services, open ports, internal network architecture etc.
• Applications - Public-facing websites, APIs, business applications, exposed databases.
• Cloud Services - Storage buckets, functions, configurations, permissions, integrations with on-prem systems.
• Users & Accounts - Employees, contractors/partners, privileged accounts, improper access controls.
• Physical Assets - Employee laptops/phones, removable media, papers/documents.

Any asset that is accessible from outside the organization's secure internal networks and systems makes up part of the attack surface. The larger this surface area, the more opportunities attackers have to gain access, breach defenses, and exfiltrate sensitive data. That's why minimizing the attack surface is critical for security.

How Digital Transformation Expands Attack Surfaces

Digital transformation initiatives aimed at boosting efficiency, agility, and connectivity have led companies to rapidly adopt cloud services, new technologies, and third-party partnerships. However, this expansion of the digital footprint has also created new security challenges:

More External Connections

• Adopting SaaS apps, IaaS cloud, and PaaS serverlessly connects internal systems and data to external providers outside the organization's firewalls.
• APIs enable integration with third-party services but increase risk if not properly secured.
• BYOD policies boost productivity but reduce control over endpoints.
• Vendor ecosystems introduce third-party risk exposure.

More Users & Accounts

• Remote/hybrid work expands access from outside corporate networks.
• Growth leads to managing more user accounts with access to data.
• Privileged accounts for IT staff and admin consoles increase insider threat risk.

Complex & Dynamic Environments

• Multi-cloud environments create management blindspots across disparate consoles.
• Frequent updates to cloud-native apps lead to misconfigurations.
• Lack of asset inventory makes it hard to track transitory resources.
• M&A activity folds in companies with unknown security postures.

This expansion introduces more assets, users, privileges, technologies, and connections - each one representing another potential target for attackers. Without minimizing the growing attack surface, organizations are unlikely to keep threats at bay.

5 Core Strategies to Reduce Your Attack Surface

Just as digital transformation increased your technology footprint and expanded the attack surface, a proactive security transformation is required to consolidate exposures and implement governance. Here are 5 keys strategies and capabilities needed:

1. Discover Your External Attack Surface

The first step is gaining complete visibility over your external-facing digital footprint. You can't secure what you can't see - so continuous discovery across the enterprise attack surface and supply chain is critical. Core capabilities needed:

Asset Discovery - Use automated scanning and analytics to identify all Internet-facing assets associated with your organization and supply chain. Maintain always up-to-date inventory.

Asset Classification - Not all assets are equal so intelligent classification identifies business criticality and functions. This enables risk-based prioritization of discovery findings.

Attack Surface Analytics - Visualize the scope of your external attack surface and analyze changes over time driven by business initiatives, M&A, or other expansion activities.

Supply Chain Coverage - Expand discovery beyond your own environment to also identify exposures stemming from third-parties, vendors, subsidiaries, and partnerships.

2. Understand Your Level of Exposure

Once you can see your attack surface, you need to analyze exposures and vulnerabilities from the perspective of an attacker. Identifying weak points and misconfigurations allows intelligent prioritization of issues based on exploitability. Key capabilities include:

Exposure Modeling - Leverage a framework that analyzes vulnerabilities, misconfigurations, outdated software, unpatched threats, and other external risk factors specific to each asset.

Continuous Monitoring - Exposure modeling provides just-in-time insights into the current state of risks and changes over time. Automated monitoring reduces reliance on point-in-time assessments.

Contextual Analytics - Not all vulnerabilities present equal risk. Analytics provide contextual insights based on severity, affected assets, and exploitable weaknesses to enable risk-based prioritization of issues.

Holistic Coverage - Expand modeling beyond your own environment to also monitor exposures stemming from third-parties, vendors, subsidiaries, and partnerships.

3. Prioritize Remediation Using Risk Analysis

The next step is to take action on exposed vulnerabilities before attackers can exploit them. With hundreds or even thousands of potential issues, intelligent prioritization based on risk analysis is key. Critical capabilities include:

Risk-Based Prioritization - Combine factors like asset importance, vulnerability severity, and exploitability to focus remediation on exposures that present higher potential impact and likelihood of compromise.

Benchmarking & Trend Analysis - Compare exposure against historical trends and peer organizations to better understand performance in business context. Is the environment getting more secure or less over time?

Remediation Management - Provide remediation teams with insights needed to formulate data-driven response plans. Maintain oversight into status of remediation efforts.

Vendor Risk Coordination - For third-party risks, coordinate with external providers to understand and remediate vulnerable exposures stemming from their environments.

4. Reduce Your Digital Footprint

In addition to remediating identified exposures, organizations also need to implement foundational practices to minimize the attack surface by reducing unnecessary ports, services, insecure protocols, and other digital footprint expansions. Key capabilities include:

Least Privilege Access - Implement zero trust principles and enforce least privilege permissions across all users, accounts, roles, applications, and infrastructure components.

Decommission Unused Assets - Actively maintain an inventory of all assets and regularly decommission unnecessary ports, services, applications, devices, and accounts no longer being used by the business.

Network Segmentation - Use VLANs, subnets, microsegmentation, and internal firewall rules to restrict lateral movement and limit access across the environment in the event of a breach.

Protocol Lockdown - Disable outdated and insecure remote access protocols like Telnet/SSHv1 and enforce modern secure protocols like SSHv2 for any required remote admin access.

5. Embed Attack Surface Visibility into Security Governance

Managing your attack surface is not a one-time project - it requires establishing ongoing governance driven by actionable metrics. Key capabilities for success include:

Executive Reporting - Provide executives and board members with reports demonstrating attack surface management program maturity, progress reducing exposures, benchmark comparisons, and investment impact.

Risk Quantification - Connect remediation investments and efforts with metrics showing hard reduction of business risk exposure over time. Demonstrate ROI.

Continuous Validation - Embed attack surface discovery and exposure analytics into existing vulnerability management, pen testing, and compliance assurance programs for continuous validation.

Security Roadmap Alignment - Ensure attack surface management and reduction activities align with and support overarching security strategies, roadmaps, and maturity models adopted by the organization.

Implementing an Attack Surface Management Program

With the right strategies and solutions in place, organizations can implement fully mature attack surface management programs that deliver the visibility, control, and risk reduction today's complex environments require. Key elements for success include:

Complete Visibility of Assets & Exposures

• Maintain always updated inventory of Internet-facing assets through continuous automated scanning.
• Monitor exposure across both your own environment and third-party ecosystem.
• Analyze attack surface scope expansion over time driven by business initiatives.

Risk-Based Remediation Prioritization

• Model external vulnerabilities from perspective of attacker exploitability.
• Quantify actual risks based on asset context and vulnerability details.
• Enable remediation teams to focus on fixing highest risk exposures first.

Effective Security Governance

• Inform security roadmaps and planning with attack surface intelligence.
• Report metrics to demonstrate risk reduction over time.
• Improve existing programs by embedding attack surface insights across key workflows.

Holistic Coverage Across Vectors

• Monitor attack surface risk factors like vulnerabilities, misconfigurations, outdated software, compromised systems, and unsecured data exposures.
• Maintain visibility across all external digital footprints - web, social media, dark web, code repositories.

Continuous Automation

• Discover new assets in real-time as they are provisioned.
• Model exposures constantly without reliance on point-in-time assessments.
• Receive alerts when high-severity events occur that require quick response.

Closing Thoughts

Today's constantly evolving threat landscape coupled with accelerated digital transformation makes minimizing your organization's attack surface crucial for security. By implementing comprehensive discovery, analytics, and governance centered around reducing external exposures, security teams can gain control over the new risks introduced as technology footprints expand. With the right strategies and solutions, you can confidently pursue business growth and cloud adoption without expanding your organization's vulnerabilities. But attack surface management is not a temporary initiative - it requires establishing continuous visibility, risk-based response capabilities, and governance that will flex and scale over time. Companies that embed these processes into their security strategies and operations will gain a major competitive advantage.

Conclusion

This guide covered what an attack surface is, how it is expanding through digital transformation, and 5 core strategies needed to reduce your organization's exposure - 1) Discover your external attack surface 2) Understand your level of exposure 3) Prioritize remediation using risk analysis 4) Reduce your digital footprint 5) Embed attack surface management into governance. Implementing capabilities in each of these areas as part of an integrated attack surface management program is key to minimizing vulnerabilities in today's complex, hybrid environments. With attackers constantly evolving and targeting weaknesses, reducing your organization's attack surface needs to become a top strategic imperative.