A Cryptographic Inventory Checklist for the Post-Quantum Era

Digital transformation has pushed cryptography into the spotlight as the unseen foundation of business security. Yet, for many organizations, this critical layer is a vast, unmapped territory. As we stand at the precipice of the quantum era, this lack of visibility is no longer a manageable risk, but it’s an existential threat. A comprehensive cryptographic inventory is not just a checklist, it’s the blueprint that will guide your organization’s journey to post-quantum readiness.

While the strategic importance of this inventory is clear, the real challenge lies in the execution. This detailed checklist goes beyond the “why” and provides a practical “what” and “how” to ensure your inventory is thorough, actionable, and robust enough to stand against the challenges ahead.

Understanding Key Inventory Principles

Before you begin collecting data, establish a clear framework. This isn’t a one-time task; it’s an ongoing process that requires continuous improvement and visibility. Your approach should be guided by these core principles:

• The Six W’s of Crypto: Every cryptographic asset in your organization must be documented with these six key details:
  1. What is the cryptographic component? This includes specific keys, digital certificates, software libraries, hardware security modules (HSMs), etc.
  2. Where is it located? This identifies its placement, whether in a specific application, on a server in a data center, within a cloud vault like Azure Key Vault, etc.
  3. When was it created, and when will it expire or be rotated? This is crucial for identifying long-lived keys that are prime targets for “harvesting.”
  4. Who is the owner or party responsible for its management and lifecycle?
  5. Why is it being used? This defines its purpose, such as protecting sensitive data for regulatory compliance like GDPR, authenticating a user, ensuring transactional integrity, and more.
  6. How is it being used? This specifies the technical details, including the specific algorithm, key length, protocol version configured, and more.
• Acknowledge Your Scope: Clearly define what’s under your direct control (your own keys, hardware, and applications) versus what’s managed by a third-party vendor. For third-party services, you must document them as “black boxes,” and your responsibility is to get a risk statement, a detailed remediation plan, and a PQC roadmap from the provider.
• Standardize and Simplify: Use consistent business processes and deployment methods wherever possible. This is the essence of crypto agility. By standardizing your approach, you simplify not only the inventory process but also future updates, patching, and new deployments.
• Be Comprehensive: Your inventory must reflect all components that could be negatively impacted by PQC advances, from legacy systems to cutting-edge technologies. No system is too small or too old to ignore.

Building Your Inventory

A single scanning tool or method won’t give you the full picture. A truly comprehensive inventory requires a multi-layered approach that combines various techniques to eliminate blind spots.

Public Key Infrastructure (PKI)

Your PKI is the digital identity system for your organization, enabling secure communication and authentication. It’s a critical area for inventory because it relies on asymmetric encryption, which is highly vulnerable to quantum attacks.

• Crypto Asset List: Create a meticulous inventory that lists all applications and communications channels that use asymmetric cryptography. This includes TLS/SSL certificates for web servers, code-signing certificates, and keys used for digital signatures and authentication.
• Key Management Audit: Verify and document your entire PKI process, including how keys are generated, stored, and rotated. Your most critical keys, such as root signing keys, should be stored in a trusted Hardware Security Module (HSM), which provides a higher level of security. Examining HSM logs can be a powerful method for discovering which applications are making cryptographic calls.
• Certificate Lifecycle Management: Document the validity periods of all your certificates. This is particularly crucial for identifying long-lived certificates (e.g., 25 years or longer), as these are prime targets for “harvesting” attacks. Just as important as validity periods is the key size and algorithm used. Even with shorter lifecycles, certificates that rely on RSA (2048/3072/4096-bit) or ECC (P-256, P-384) are still vulnerable to quantum attacks, since Shor’s algorithm can break them regardless of key length. To mitigate this, create a process not only to regularly review and re-issue certificates with shorter lifecycles but also to catalog the algorithms and key sizes in use. This visibility will help prioritize which certificates pose the greatest quantum risk and should be transitioned first to quantum-resistant or hybrid cryptographic models.

Application Development (AppSec)

Cryptography is often embedded deep within applications, making it hard to find and manage. To build an effective inventory, you’ll need to leverage multiple discovery methods:

• Self-Identification: A simple and effective starting point is to expand your existing application inventory. Require application owners to explicitly record whether their application uses encryption, what type it is, and a brief description of its usage. This first-line data provides a crucial starting point for more technical discovery.
• Static Scanning: Integrate static code analysis tools into your CI/CD pipelines. These tools can scan code to find cryptographic function calls. While they may not be perfectly precise (e.g., they might show all available algorithms in a library, not just those in use), they are an excellent way to quickly identify which applications are calling algorithms that are no longer considered PQC-safe, like RSA and ECDSA.
• Dynamic Analysis: For a more accurate, run-time view, use Interactive Application Security Testing (IAST) tools. These tools have visibility into the cryptographic functions that are actually being used by an application, including calls from third-party libraries and framework components. This approach complements static scanning by showing “what’s really happening.”
• Software Bill of Materials (SBOM): As SBOMs become more widespread, they will provide a valuable “list of ingredients” for software components. You can use this to map cryptographic libraries and identify known vulnerabilities.
• File System Discovery: Use file system scans with tools like Tanium or Varonis to find cryptographic components like keys, key stores, and certificates. Be aware that this method can produce a lot of noise, so it’s best used in conjunction with other methods to confirm what’s actually in use.

Other Critical Considerations

Cryptography isn’t limited to traditional servers and applications. Your inventory must also account for these specialized asset classes:

• SaaS Providers: Don’t assume your data is safe just because it’s in the cloud. Document the encryption algorithms used by your SaaS providers. Understand their key management model: is it SaaS-managed, Bring Your Own Key (BYOK), or do they allow for customer-managed keys? Ask for their PQC plan and timeline, especially if they use older algorithms.
• Hardware Security Modules (HSMs): HSMs contain an organization’s most important keys. They must be included in your inventory. Beyond simply listing the HSMs, you should examine their logs to identify which applications are making calls to perform cryptographic functions, providing a more detailed view of usage.
• APIs, IoT, and Blockchain: These are separate asset classes that each present unique PQC risks. For APIs, document their use of encryption and ensure their connection ciphers are strong. For IoT, catalog all devices and their embedded crypto, as updating firmware can be a challenge. For blockchain, you must understand its usage of public-key cryptography, which is vulnerable to PQC risks.

The Journey of Continuous Improvement

Building and maintaining this inventory is a journey, not a destination. It requires continuous effort and a well-defined process to remain accurate and relevant.

• Start with a CBOM: Use your initial inventory to create a Cryptographic Bill of Materials (CBOM), which provides a comprehensive, structured view of your crypto usage.
• Frequency of Scans: Determine the appropriate frequency of scans based on risk and change activity. More critical areas should be scanned more often.
• Address Blind Spots: Acknowledge that some keys may be offline or in inaccessible locations. Develop alternative methods to find them or make assumptions where validation isn’t possible.
• Develop Awareness: Provide training to your development and security teams to embed crypto agility into your culture and processes.
• Monitor and React: Create a process for handling exceptions and alerts triggered by monitoring (e.g., an algorithm being deprecated or a key expiring).

How Encryption Consulting Can Help

Building a comprehensive cryptographic inventory is a huge undertaking, but you don’t have to do it alone. We are a globally recognized leader in applied cryptography, offering Post-Quantum Cryptography (PQC) Advisory Services specifically designed to help organizations like yours navigate the quantum shift.

Our services are built on a structured, end-to-end approach:

• PQC Assessment: We perform cryptographic discovery and inventory to locate all your keys, certificates, and dependencies. This delivers a clear Quantum Threat Assessment and a Quantum Readiness Gap Analysis that identifies your vulnerabilities and most urgent priorities.
• PQC Strategy & Roadmap: Based on the inventory data, we help you develop a custom, phased PQC migration strategy aligned with NIST and other industry standards. This includes creating a Cryptographic Agility Framework to ensure you’re prepared for future changes.
• Vendor Evaluation and PoC: We assist in selecting the best PQC solutions by defining evaluation criteria, shortlisting vendors, and executing proof-of-concepts (PoCs) on your critical systems to validate their effectiveness.
• PQC Implementation: We help you seamlessly integrate PQC algorithms into your PKI and other security ecosystems, including the deployment of hybrid cryptographic models for a secure and disruption-free transition.

With our deep expertise and proven framework, you can build, assess, and optimize your cryptographic infrastructure, ensuring a smooth and secure transition to a post-quantum future.

Conclusion

The quantum era will not wait for organizations to catch up. A comprehensive cryptographic inventory is the cornerstone of true post-quantum readiness, giving you the visibility and control needed to protect your most critical assets. By moving beyond theory to a structured, actionable checklist, you can uncover hidden risks, strengthen crypto agility, and prepare your infrastructure for the inevitable transition.

With the right approach, and the right partners, you can turn today’s uncertainty into tomorrow’s resilience. Start building your cryptographic inventory now to ensure your organization is not just quantum-aware, but quantum-ready.