CDE Attack Surface Inventory
In the context of cybersecurity, CDE Attack Surface Inventory refers to the comprehensive and continuous process of identifying and cataloging all potential points or vectors through which an unauthorized entity (e.g., an attacker) could attempt to gain access to, compromise, or exfiltrate data from a Cardholder Data Environment (CDE). The CDE is the part of an organization's network that stores, processes, or transmits sensitive payment card information.
This inventory goes beyond simply listing known assets. It involves a detailed examination of:
Network Perimeter: Identifying all internet-facing devices, systems, and services that could potentially lead to or interact with the CDE. This includes public IP addresses, domains, subdomains, open ports, firewalls, routers, and internet-facing applications.
Applications: Cataloging all web applications, mobile applications, APIs, and other software components that directly handle cardholder data or could provide a pathway to it. This includes understanding their versions, configurations, and known vulnerabilities.
Data Storage Locations: Identifying where cardholder data is stored, both at rest and in transit, across all systems, databases, cloud services, and even third-party environments. This includes understanding data retention policies and encryption status.
Third-Party Connections: This maps out all connections to external entities, such as payment gateways, service providers, cloud vendors, and business partners, that interact with the CDE. It assesses the risk introduced by their own security posture.
Personnel and Access Points: Identifying all individuals, accounts, and methods (e.g., VPNs, remote access tools) that have access to the CDE, focusing on authentication mechanisms and least privilege principles.
Code and Development Environments: Discovering publicly exposed code repositories or development/test environments that might contain sensitive information (like credentials or configurations) that could inadvertently lead to CDE compromise.
Digital Footprint beyond direct control: This includes identifying brand impersonations, typosquatted domains, and dark web mentions that could be used for phishing or other social engineering attacks targeting employees with CDE access.
The purpose of a CDE Attack Surface Inventory is to provide a complete and dynamic picture of an organization's exposure, enabling security teams to:
Scope the CDE Accurately: Ensure all components that store, process, or transmit cardholder data are identified and included in PCI DSS compliance efforts.
Identify Unknown Assets (Shadow IT): Uncover systems or applications that are managing sensitive data but are not formally tracked or secured by IT, posing significant risks.
Prioritize Vulnerability Management: Focus remediation efforts on external exposures that present the most direct threat to the CDE.
Strengthen Network Segmentation: Verify that logical and physical segmentation controls effectively isolate the CDE from other networks.
Improve Incident Response: Have a clearer understanding of potential entry points and compromised assets in the event of a breach.
Reduce the Attack Surface: Proactively close or secure unnecessary exposures, thereby minimizing opportunities for attackers to gain a foothold.
This inventory should not be a one-time exercise but a continuous process, as the CDE and its surrounding environment constantly evolve with new deployments, configurations, and third-party integrations.
ThreatNG is an all-in-one external attack surface management, digital risk protection, and security ratings solution that can help organizations create and maintain a robust CDE Attack Surface Inventory. It does this by providing an "outside-in" perspective, identifying elements of the CDE and its surrounding environment that are visible to attackers.
External Discovery & Continuous Monitoring
ThreatNG performs purely external, unauthenticated discovery, meaning it identifies assets and risks from an attacker's perspective without needing connectors. This is crucial for a CDE Attack Surface Inventory because it helps organizations discover unknown or rogue assets that might be storing, processing, or transmitting cardholder data (CHD) and fall within the scope of PCI DSS. ThreatNG monitors an organization's external attack surface, digital risk, and security ratings. This continuous monitoring ensures that new exposures or changes to existing assets that could impact the CDE are immediately identified and added to the inventory.
Examples of ThreatNG's help:
Identifying Rogue Applications: ThreatNG can discover "Applications Identified" and login pages the organization may not have been aware of. If these applications handle CHD, they must be inventoried and secured according to PCI DSS Requirement 1.4.2 (maintaining an inventory of system components in scope). ThreatNG's discovery helps ensure all such interfaces are known, tracked, and subject to proper security governance, thus improving the CDE Attack Surface Inventory.
Detecting Exposed Developer Resources: ThreatNG can find "Developer Resources Mentioned" and environments exposed externally. If these environments are not segmented from production or are not using real CHD, they pose a direct risk to the CDE. ThreatNG's continuous monitoring would flag such exposures, ensuring they are documented in the CDE Attack Surface Inventory and remediated.
ThreatNG performs various external assessments that directly contribute to building and maintaining a comprehensive CDE Attack Surface Inventory:
Cyber Risk Exposure: This assessment considers parameters like certificates, subdomain headers, vulnerabilities, and sensitive ports. It also factors in "Code Secret Exposure", which involves discovering code repositories and investigating their contents for sensitive data. These critical components of an attack surface inventory could lead to CDE compromise.
Example: ThreatNG detecting "Invalid Certificates" or "Subdomains Missing Strict Transport Security (HSTS) Header" highlights weaknesses in data-in-transit protection. While not directly CHD, these insecure configurations on public-facing assets could be part of an attack chain leading to the CDE, and thus must be included in the CDE Attack Surface Inventory for remediation.
Cloud and SaaS Exposure: ThreatNG evaluates sanctioned and unsanctioned cloud services and Software-as-a-Service (SaaS) solutions. This is crucial for a CDE Attack Surface Inventory, as many organizations use cloud services to store or process CHD, and unknown or misconfigured instances pose a significant risk.
Example: ThreatNG discovering "Files in Open Cloud Buckets" directly highlights a data exposure risk that could include CHD. This finding immediately adds a critical, potentially overlooked, component to the CDE Attack Surface Inventory, which must then be addressed per PCI DSS 3.1.1 (retain cardholder data only if required).
Mobile App Exposure: ThreatNG evaluates an organization's mobile app exposure by discovering them in marketplaces and analyzing their content for sensitive credentials and identifiers. Mobile applications can directly interact with or expose CHD.
Example: ThreatNG identifying "Mobile Application Exposure Sensitive Information Found" means sensitive data, such as access credentials, is present within mobile applications. These mobile app components become part of the CDE Attack Surface Inventory and require immediate attention per PCI DSS 3.2 (do not store sensitive authentication data) and 3.4 (encrypt sensitive data in storage).
Breach & Ransomware Susceptibility: This assessment considers exposed sensitive ports, private IPs, and known vulnerabilities. These findings directly inform the CDE Attack Surface Inventory by identifying specific points of weakness that attackers could target.
Example: ThreatNG discovering "Private IPs Found" in public DNS highlights a significant security risk, as it reveals internal network architecture. This exposure undermines network segmentation (PCI DSS 1.1.1) and directly adds these internal IPs to the external CDE Attack Surface Inventory, requiring immediate remediation.
ThreatNG provides comprehensive reports, including an "Inventory" report and "External GRC Assessment Mappings (e.g., PCI DSS)". These reports are invaluable for building and maintaining a CDE Attack Surface Inventory:
The Inventory report lists all discovered assets, directly supporting the creation and maintenance of the CDE Attack Surface Inventory.
External GRC Assessment Mappings allow organizations to see how discovered external risks align with PCI DSS requirements. This helps prioritize additions and updates to the CDE Attack Surface Inventory based on compliance implications.
ThreatNG's core capability includes "Continuous Monitoring of external attack surface, digital risk, and security ratings of all organizations". This is fundamental to a CDE Attack Surface Inventory, as the attack surface is dynamic. New assets, misconfigurations, or exposed data can appear at any time. Continuous monitoring ensures that the inventory remains up-to-date, providing real-time visibility into new components that fall into the CDE scope or pose a risk to it.
ThreatNG's investigation modules provide detailed insights that are critical for populating and enriching the CDE Attack Surface Inventory:
Domain Intelligence: This module comprehensively overviews an organization's digital presence, including DNS Intelligence (Domain Record Analysis, Domain Name Permutations, Web3 Domains), Email Intelligence, WHOIS Intelligence, and Subdomain Intelligence.
Example: Through Subdomain Intelligence, ThreatNG can identify "APIs on Subdomains." If they handle payment data, these APIs are critical components of the CDE, and ThreatNG's discovery ensures they are included in the CDE Attack Surface Inventory and subjected to secure coding practices (PCI DSS 6.5.1) and penetration testing (PCI DSS 11.3.1).
Example: When ThreatNG performs a "Default Port Scan" as part of its Subdomain Intelligence, it identifies externally exposed ports. Suppose SSH, RDP, or database ports are found to be open. This indicates potential unauthorized access points that must be documented in the CDE Attack Surface Inventory and secured with firewalls (PCI DSS 1.2) and secure configurations (PCI DSS 2.2).
Sensitive Code Exposure: This module discovers sensitive information within public code repositories.
Example: If ThreatNG finds "Code Secrets Found," such as API keys or database credentials, in a public repository, these represent potential backdoor access points to systems within or connected to the CDE. These exposed secrets immediately become critical entries in the CDE Attack Surface Inventory, demanding immediate remediation to prevent unauthorized access (PCI DSS 7.1).
Cloud and SaaS Exposure: ThreatNG discovers "Open Exposed Cloud Buckets" and various SaaS implementations.
Example: Discovering an "Open Exposed Cloud Bucket" through Cloud and SaaS Exposure directly reveals an unintended storage location that might contain CHD. This immediately adds the bucket to the CDE Attack Surface Inventory, highlighting the need to restrict access based on need-to-know (PCI DSS 7.2.1) and ensure unreadable stored PAN (PCI DSS 3.4.1).
Intelligence Repositories (DarCache)
ThreatNG's continuously updated intelligence repositories provide vital context for enriching the CDE Attack Surface Inventory:
Vulnerabilities (DarCache Vulnerability): This includes NVD, EPSS, KEV, and Verified Proof-of-Concept (PoC) Exploits.
Example: "DarCache KEV" identifies vulnerabilities actively exploited in the wild. If ThreatNG detects an internet-facing asset (identified in the CDE Attack Surface Inventory) with a KEV vulnerability, this indicates an immediate, proven threat. This information allows for rapid patching prioritization, fulfilling PCI DSS 6.2.3 (addressing security vulnerabilities).
Mobile Apps (DarCache Mobile): This repository details findings within discovered mobile applications, including access and security credentials.
Example: "DarCache Mobile" can reveal that a mobile application associated with the organization exposes "Amazon AWS Access Key ID". If found on a mobile app related to the CDE, this sensitive credential would be a critical entry in the CDE Attack Surface Inventory, mandating immediate credential revocation and secure development practices (PCI DSS 6.3).
Working with Complementary Solutions
ThreatNG's capabilities create powerful synergies when combined with other cybersecurity solutions, significantly enhancing the creation and maintenance of a CDE Attack Surface Inventory.
Configuration Management Databases (CMDBs): ThreatNG's external discovery directly feeds newly identified assets and misconfigurations into a CMDB.
Example: When ThreatNG identifies "Applications Identified" or "Private IPs Found" that were previously unknown to the organization, this data can be automatically populated into the CMDB. This ensures the CMDB, which serves as the core for the CDE Attack Surface Inventory, is complete and accurate, aligning with PCI DSS Requirement 1.4.2 for maintaining an inventory of system components.
Vulnerability Management (VM) Platforms: ThreatNG's external assessment capabilities, particularly its identification of "Critical Severity Vulnerabilities Found" and "High Severity Vulnerabilities Found", provide a crucial external perspective that complements VM platforms.
Example: ThreatNG can flag an exposed web application with a critical vulnerability. This finding can then be pushed to a VM platform to initiate deeper, authenticated scans of the internal components of that application. This combined approach ensures that both external and internal vulnerabilities that could expose the CDE are identified and prioritized for remediation, supporting PCI DSS 6.2.3 (addressing security vulnerabilities) and 11.3.1 (annual external penetration testing).
Cloud Security Posture Management (CSPM) Tools: ThreatNG's "Cloud and SaaS Exposure" capability identifies externally exposed cloud resources.
Example: ThreatNG might discover an "Open Exposed Cloud Bucket" that could potentially contain CHD. This external finding can trigger a more granular internal scan by a CSPM tool to confirm data presence, assess misconfigurations, and ensure access controls are aligned with PCI DSS 7.2.1 (restrict access based on need-to-know) and 3.4.1 (render stored PAN unreadable). The CSPM tool can then continuously monitor the cloud environment for new exposures, enriching the CDE Attack Surface Inventory.
Incident Response (IR) Platforms: ThreatNG's continuous monitoring provides real-time alerts on significant external exposures that could lead to a breach of the CDE.
Example: If ThreatNG detects "Compromised Emails" that are linked to individuals with access to the CDE, or a "Subdomain Takeover" that could be used for phishing, this intelligence can automatically trigger an incident response playbook in an IR platform. This allows for a swift and coordinated response, including immediate investigation of affected CDE components, in line with PCI DSS 12.10.5 (responding to alerts from detection systems).
Security Information and Event Management (SIEM) Systems: ThreatNG's findings from its various assessment modules can be integrated into a SIEM.
Example: Details about "Admin Page References" or "Custom Port Scan" results revealing unexpected open ports can be fed into the SIEM. The SIEM can then correlate these external insights with internal log data to detect suspicious activities targeting these newly identified or unmanaged attack surface components. This combined visibility supports PCI DSS 10.2.1 (logging access to system components) and 10.6.1 (monitoring and responding to security alerts).
