Choose a maintained, high level library that makes the safe choice the default: it picks the algorithm and mode, generates nonces itself, and hands you one call to encrypt and one to decrypt. Avoid assembling raw primitives yourself. CWE-327 advises using vetted libraries and never custom cryptography.
Why the library matters more than the algorithm
AES is not the usual failure. The failures sit around it: a wrong mode, a reused nonce, a skipped authentication check, a key in source code. A library that removes those choices removes the failures.
CWE-327 lists the mitigations plainly: use strong current algorithms in well tested implementations, do not develop custom or private algorithms, use vetted libraries or frameworks, design for crypto agility, and protect keys, since guessed or stolen keys make the algorithm's strength irrelevant.
Two examples of the high level style
libsodium describes itself as a modern, easy to use software library for encryption, decryption, signatures, password hashing and more, with design choices that emphasize security and ease of use. It is cross platform and cross language, with JavaScript and WebAssembly versions supported.
Tink, from Google, calls itself a multi language, cross platform, open source library that provides secure and easy to use cryptographic APIs. Its documentation points to a separate section on generating and managing keys.
These are examples of the style, not a ranking. Whatever you pick should be judged against the checklist below.
A selection checklist
| Question | Good sign | Warning sign |
|---|---|---|
| Who maintains it? | Active, named maintainers | Last release years ago |
| API level | Encrypt and decrypt calls with safe defaults | You choose mode, padding and IV |
| Nonce handling | Generated by the library | You must supply one |
| Authentication | Built in to encryption | Optional or separate |
| Key management | Key objects, rotation support | Raw byte strings only |
| Advisory history | Fixed quickly, documented | Silent or ignored issues |
How to evaluate in an hour
- Write the shortest encrypt and decrypt example from the documentation. Count the decisions you had to make.
- Try to misuse it on purpose: reuse a nonce, truncate the tag, pass the wrong key. Does it refuse?
- Check the project's advisory page and release cadence.
- Check whether your platform has a validated build, if your customers ask for one.
- Look at how it handles key rotation and key identifiers.
- Read the license and check that it fits how you ship.
After you choose
Wrap the library in one small module in your codebase. Every encrypt and decrypt call goes through it. That gives you one place to review, one place to log, and an easy swap if the library is retired, which is the practical meaning of crypto agility.
Keep the dependency current. A good library still ships security fixes, and you only benefit if you install them. Track it in your inventory like any other component.
Try it yourself
Open the dependency inventory demo and find a crypto package in the list. Notice how version and advisory information sit together, and think about how you would know if your chosen library had a fix available.
Click through it at your own pace, or open it full screen.
Safeguard can generate an SBOM and scan your dependencies, so outdated cryptography libraries with known advisories show up in one inventory, and policies can gate a build on them. A free scan is at gold.safeguard.sh/scan.
Quick check
Is it fine to use the crypto module built into my language?
Often yes, and it is usually well maintained. The risk is the low level surface, so wrap it and follow current guidance for modes and nonces.
Should I write my own wrapper around primitives?
Keep wrappers thin and about policy, such as logging and key ids. Do not implement the algorithms or invent a protocol.
Sources
Last reviewed: 19 October 2026.
