Shadow in the Cloud: Why EASM Must Uncover Your Unknown Cloud & CDN Assets

Imagine the chaos: a Fortune 500 retailer, fresh off a record-breaking Black Friday, receives a cryptic email from a security researcher: "Your customer data is exposed on Google. Thought you should know." The link leads to an abandoned AWS S3 bucket containing thousands of customer invoices, credit card details, and purchase histories—indexed by search engines and accessible to anyone. This forgotten bucket, a relic of a short-lived marketing campaign, had been leaking sensitive data for months.

This wasn’t a sophisticated cyberattack. It was a preventable oversight caused by shadow IT—an all-too-common issue in today’s cloud-driven world. As organizations race to adopt cloud services and Content Delivery Networks (CDNs), their external attack surfaces are expanding faster than their ability to secure them. 

Enter External Attack Surface Management (EASM), a critical cybersecurity discipline that uncovers hidden cloud and CDN assets before attackers exploit them. This blog explores why EASM is indispensable, supported by market insights and real-world examples.

The Cloud and CDN Boom: Opportunity and Risk

The rapid adoption of cloud services and CDNs has transformed how businesses operate, enabling scalability and global performance. However, this digital acceleration comes with a hidden cost: an ever-expanding attack surface. Misconfigured cloud buckets, orphaned subdomains, and forgotten CDN endpoints create vulnerabilities that attackers eagerly exploit.

• Market Insight: The global cloud discovery market is projected to reach USD 4.1 billion by 2030, growing at a CAGR of 16.4% from 2024, driven by widespread cloud adoption and AI integration.
• CDN Growth: The CDN market, valued at USD 23.69 billion in 2024, is expected to soar to USD 73.48 billion by 2033, with a CAGR of 11.98%, fueled by demand for streaming and e-commerce.
• Security Stakes: The cloud security segment within the CDN market is growing at a 14% CAGR through 2029, as organizations prioritize protection against threats like DDoS attacks and data breaches.

These statistics highlight the explosive growth of cloud and CDN infrastructure and the corresponding rise in cyber risks. The challenge? Many organizations don’t even know what assets they have exposed online.

How EASM Illuminates the Shadows

EASM addresses this blind spot by providing continuous discovery and monitoring of internet-facing assets, including cloud infrastructure (e.g., AWS, Azure, Google Cloud) and CDNs (e.g., Akamai, Cloudflare, Fastly). Unlike traditional security tools, EASM takes an outside-in approach, mimicking how attackers scout for vulnerabilities. It leverages DNS analytics, SSL/TLS fingerprinting, passive DNS, and threat intelligence to uncover:

• Cloud Infrastructure (AWS, Azure, GCP): Uncovers S3 buckets, VMs, APIs, and more
• CDNs (Akamai, Cloudflare, Fastly): Identifies misconfigured or forgotten endpoints
• Shadow IT: Flags unauthorized cloud services introduced outside IT’s purview
• Third-Party Assets: Detects dependencies and integrations that expand risk

By mapping these assets, EASM enables organizations to answer critical questions: What’s exposed? Who owns it? Is it vulnerable? Could it be exploited?

Real-World Examples of EASM in Action

1. SolarWinds Attack (2020): The SolarWinds Orion software breach exploited a vulnerability in a widely used IT management tool, affecting numerous organizations. EASM could have helped by identifying exposed assets running vulnerable versions of the software. For instance, Detectify added the zero-day vulnerability (CVE-2020-10148) to its EASM scanner, enabling organizations to detect and mitigate risks in their external assets, including those hosted on cloud infrastructure. This highlights the importance of continuous monitoring to catch vulnerabilities in third-party dependencies.
2. Unsecured Database Exposure: A multinational corporation suffered a data breach when an unprotected database was left exposed in a cloud environment. EASM tools identified this shadow IT asset by scanning for misconfigured cloud resources, such as publicly accessible S3 buckets, alerting the security team before attackers could cause further damage. This case highlights EASM’s role in uncovering hidden cloud assets.
3. CDN Misconfiguration at a Media Company: A global media company using a CDN for streaming content discovered a misconfigured subdomain tied to a test environment. The subdomain, hosted on a CDN, was publicly accessible and lacked security updates. An EASM solution traced it to a CDN-hosted IP through recursive discovery, enabling the company to secure it before exploitation. This demonstrates EASM’s ability to pinpoint CDN-specific risks.
4. Lookalike Domain Phishing Campaign: Cybercriminals created lookalike domains mimicking a financial institution’s primary domain, hosted on a CDN for credibility. An EASM tool analyzed SSL certificates and DNS records to flag these domains, allowing the organization to initiate takedowns before phishing campaigns caused significant harm. This underscores EASM’s effectiveness in combating impersonation risks.

Why Traditional Tools Fall Short

Traditional security tools like Dynamic Application Security Testing (DAST), Static Application Security Testing (SAST), and Security Information and Event Management (SIEM) are powerful but limited. They require predefined targets and struggle to identify unknown assets. EASM, by contrast, starts with an organization’s digital footprint—known and unknown—and systematically uncovers:

• Assets obscured by CDN configurations.
• Orphaned cloud services from mergers, acquisitions, or contractor projects.
• Subdomains linked to decommissioned environments.
• Third-party assets that inherit brand reputation risks.

This outside-in perspective makes EASM uniquely suited to today’s dynamic cloud and CDN environments.

The Challenges - and the Fix

Cloud and CDN ecosystems are inherently fluid, with assets frequently spun up or decommissioned. This creates challenges that EASM addresses:

The Future of EASM in Cloud and CDN Security

As cloud and CDN adoption continue to grow, EASM is evolving to meet the increasing complexity of modern attack surfaces:

• AI-Powered Discovery: Machine learning is enhancing EASM’s ability to detect high-risk assets and anomalies, often before a known vulnerability is present.
• Smarter Asset Attribution: Advanced correlation techniques help identify ownership, context, and configuration risks across dynamic cloud and CDN environments.
• Continuous Threat Exposure Management (CTEM): Gartner predicts that organizations implementing CTEM strategies — with EASM as a foundational capability — will experience two-thirds fewer breaches by 2026.

These advancements underscore EASM’s critical role in proactive cybersecurity, enabling security teams to identify, assess, and mitigate risks before they’re exploited.

Conclusion: See It, Secure It

Your cloud and CDN infrastructure is growing—often faster than your ability to track it. Attackers exploit these gaps, turning forgotten assets into liabilities. EASM closes this visibility gap, empowering organizations to discover, assess, and secure their external attack surface.

Don’t wait for a security researcher’s email to expose your vulnerabilities. Invest in EASM to uncover your hidden cloud and CDN assets and take control of your digital frontier. Ready to start? Contact us to request a ZeroFox External Attack Surface Risk Assessment.