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Comment by francislavoie | Hacker News Reader

Watch the talk at the bottom of the page. JWT/JOSE are chock full of dangerous footguns that aren't just theoretical, they have repeatedly been shown to be poorly designed and too risky to implement correctly as written. Using fewer, known secure cryptographic primitives as part of the spec ensures it's impossible to get the security wrong, can't be misused.

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I am not going to watch the talk. The slides from it are unavailable either.

And sorry, but the article https://paragonie.com/blog/2017/03/jwt-json-web-tokens-is-ba... is just weak. The only real vulnerability is the key type confusion (HS256 vs. RSA256) enabled by libraries in weakly-typed languages, and easily fixed. Other:

> RSA with PKCS #1v1.5 padding is vulnerable to a type of chosen-ciphertext attack, called a padding oracle.

Not applicable.

> If you attempt to avoid invalid curve attacks by using one of the elliptic curves for security, you're no longer JWT standards-compliant.

This is just nonsense. JWT allows Ed25519: https://www.rfc-editor.org/rfc/rfc8037 Moreover, I'm not aware of real attacks against NIST curves.

The point is that the JWT spec leaves it open to the implementer which primitives to use, which invites bad implementations to be insecure. PASETO requires a small subset of known secure primitives, preventing that problem altogether. It's not "just nonsense".

Here's a list of "alg: none" JWT vulns. Every one of these would've been avoided had the standard been something like PASETO which didn't allow that. https://github.com/zofrex/howmanydayssinceajwtalgnonevuln/bl...

You say "I am not going to watch the talk" and then you continue to argue in bad faith. Please walk away if you're not going to engage honestly.

The JWT spec can thus be fixed by changing the recommended set of primitives. No need to reinvent the wheel with custom serialization (that probably also has vulnerabilities when implemented by clueless people).

You parade the alg=none vulnerability that has been fixed long ago as the reason to reinvent the world. It's simply not.

The spec is fundamentally flawed. The fixed spec would be a different spec, i.e. something like PASETO.

You keep repeating that. What is "fundamentally flawed"?

PASETO has exactly the same vulnerabilities. You can specify a different version, and a buggy implementation can misinterpret it. With PASETO, the algorithm selection is fully under the control of the attacker.

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