Build a cryptographic inventory before your encryption becomes a mystery box. If you do not know where your keys, certificates, algorithms, and crypto libraries live, you cannot protect them. You also cannot replace them fast when something breaks.
TLDR: A cryptographic inventory is a clear list of all cryptography used across your organization. It tracks things like TLS certificates, encryption keys, hashing algorithms, crypto libraries, owners, systems, and expiry dates. For example, a company with 240 public certificates might discover that 18 expire within 30 days and 6 use weak settings. That is boring data until one expired certificate takes checkout offline at 2:13 a.m.
What is a cryptographic inventory?
A cryptographic inventory is a map of your cryptographic assets.
That sounds fancy. It is not.
It is a list that answers simple questions:
- What encryption do we use?
- Where is it used?
- Who owns it?
- When does it expire?
- Is it strong enough?
- What breaks if we change it?
Think of it like a kitchen pantry, but for secrets. You do not want to find a 2012 can of beans during an emergency. You also do not want to find a forgotten SHA-1 certificate during an audit.
A good inventory includes:
- Certificates, such as TLS, code signing, client, and internal certificates.
- Encryption keys, such as database keys, API keys, SSH keys, and cloud KMS keys.
- Algorithms, such as RSA, AES, ECC, SHA-256, and older weak choices.
- Protocols, such as TLS 1.2, TLS 1.3, SSH, IPsec, and mTLS.
- Crypto libraries, such as OpenSSL, BoringSSL, Java crypto, and .NET crypto packages.
- Dependencies, such as apps, services, servers, containers, APIs, and vendors.
Why organizations need one
Because cryptography hides everywhere.
It hides in web servers. It hides in mobile apps. It hides in containers. It hides in old Java services that nobody wants to touch. It hides in vendor tools with admin panels that still look like 2009.
Honestly, it feels like encryption was designed by careful engineers and then scattered by raccoons.
Without an inventory, teams guess. Guessing is not a security plan. It is a slow path to outages, audit pain, and late-night calls.
1. Certificate outages are painfully common
An expired certificate can stop users from logging in. It can block payments. It can break APIs. It can also make internal services panic like toddlers with no snacks.
In many organizations, certificates are owned by different teams. Some are in public cloud. Some are in load balancers. Some are in Kubernetes secrets. Some were created by “Steve,” who left three years ago.
A cryptographic inventory prevents this. It shows expiry dates and owners. It sends alerts before the fire starts.
2. Weak crypto does not announce itself
Old algorithms can sit quietly for years. MD5. SHA-1. RSA 1024. TLS 1.0. They may still work, which is the annoying part.
Attackers love old crypto. Auditors do not.
An inventory helps you find weak algorithms and replace them. It also helps you prove that replacements happened.
3. Post-quantum planning needs facts
Quantum-safe migration is not a “someday” spreadsheet problem. It starts with knowing where public-key cryptography exists.
RSA and ECC are used in certificates, VPNs, signing systems, identity tools, and device communication. If you cannot list them, you cannot plan the move.
A cryptographic inventory gives you the starting line.
4. Incidents move faster with a map
Imagine a crypto library has a serious bug. You need to know where it is used. Fast.
If you have an inventory, you search. If you do not, expect to waste time asking five teams, checking twelve repos, and finding one forgotten service after lunch.
That gap matters. During a real incident, ten minutes can feel rude.
What to track in a cryptographic inventory
Start simple. Then grow.
Your inventory should track the details below.
Certificates
- Common name and subject alternative names.
- Issuer, such as a public CA or internal CA.
- Expiry date.
- Key size and algorithm.
- Where it is installed.
- Owner and backup owner.
- Renewal method, manual or automated.
Pay close attention to wildcard certificates. They are useful. They are also risky. One leak can affect many systems.
Encryption keys
- Key type, such as symmetric, asymmetric, SSH, or API key.
- Storage location, such as HSM, KMS, vault, file, or secret manager.
- Creation date.
- Rotation date.
- Access permissions.
- Business owner.
- Systems that use it.
Never store the raw secret in the inventory. Store metadata. The inventory is a map, not the treasure chest.
Algorithms and protocols
Track which algorithms and protocols are used. Mark weak ones clearly.
- Approved: AES-256, SHA-256, TLS 1.2, TLS 1.3, modern ECC.
- Needs review: RSA with small keys, old cipher suites, custom crypto.
- Retire: MD5, SHA-1, SSL, TLS 1.0, TLS 1.1.
Custom crypto deserves a red flag. It may be brilliant. It may also be a glitter-covered trap.
Cryptographic dependencies
This part is often missed.
Crypto is not only certificates and keys. It is also software that performs cryptographic work.
Track:
- Crypto libraries and versions.
- Apps that call those libraries.
- Containers that package them.
- Third-party services that handle encryption.
- Hardware security modules.
- Cloud KMS resources.
- Build pipelines that sign code.
This helps during patching. It also helps when a vendor changes support rules or a library reaches end of life.
How to create a cryptographic inventory
You do not need a perfect tool on day one. You need momentum.
Step 1: Scan what is easy
Start with external certificates. Scan your public domains. Then scan internal networks. Add cloud load balancers, API gateways, and Kubernetes ingress points.
Use certificate discovery tools. Use cloud APIs. Use configuration management data. Pull from CI/CD systems. Check secrets managers.
Yes, some tools are clunky. One scanner may take 40 seconds to return results that should take 5. Fine. Start anyway.
Step 2: Add owners
Every item needs an owner. Not “IT.” Not “platform.” A real team or person.
Add a backup owner too. People take holidays. People change roles. People flee old ticket queues.
Step 3: Rate risk
Score each item. Keep it simple.
- High risk: expires soon, internet-facing, weak algorithm, unknown owner.
- Medium risk: internal but business critical, manual renewal, unclear dependency.
- Low risk: automated, strong settings, clear owner, monitored.
This helps teams fix the worst items first.
Step 4: Automate updates
A stale inventory is just a scrapbook.
Connect it to real sources. Pull data from cloud accounts, certificate authorities, vaults, endpoint tools, source code scans, and asset databases.
Set alerts for:
- Certificates expiring in 30, 15, and 7 days.
- New weak algorithms.
- Keys with no rotation date.
- Unknown owners.
- Unexpected certificate issuers.
Step 5: Make it part of change management
New service? Add crypto details.
New certificate? Add owner and expiry.
New library? Add version and usage.
This keeps the inventory alive. It also stops teams from creating secret little crypto islands.
Who should own the inventory?
Security should guide it. Platform and infrastructure teams should feed it. Application teams should confirm the details. Compliance teams should use the reports.
Do not make it one person’s side quest. That ends badly.
A simple operating model works well:
- Security: policy, risk scoring, approved algorithms.
- Infrastructure: certificates, networks, load balancers, cloud keys.
- Developers: app crypto, libraries, signing, dependencies.
- Compliance: evidence and audit reporting.
Common mistakes to avoid
- Only tracking public certificates. Internal certs break things too.
- Skipping owners. An asset with no owner is future pain.
- Storing secrets in the inventory. Do not do this. Ever.
- Ignoring vendors. Third parties handle crypto on your behalf.
- Making the inventory manual only. Manual data rots fast.
The simple goal
A cryptographic inventory does not need to be glamorous. It needs to be accurate enough to answer urgent questions.
What do we use? Where is it? Who owns it? Is it safe? When must it change?
If you can answer those questions quickly, you are in a much better place. Your audits get easier. Your outages shrink. Your crypto migration plans stop being guesswork.
Start with certificates. Add keys next. Then track algorithms, libraries, and dependencies. Keep it updated. Keep it boring. Boring crypto is usually good crypto.
