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by tracker1 2 hours ago
JWTs are insecure... even when using trusted, rsa/ppk based signing methods? not shared secrets.

JWTs are too long lived... Nothing is stopping you from limiting the JWT lifetime and having a refresh model against an authentication authority... I mean, even if you use cookie based sessions, you're storing somewhere... you can have a jwt valid for 5-15min. 15minutes is roughly the cache timing for many authorization systems including Entra... and even a 5min token with a refresh system can be used fine from a browser.

Lastly, I prefer to have identity/auth separated from the application/api services... it externalizes context and JWT per request is easier to deal with than some shared cache/state system that may intermittently fail as opposed to a signed token that you can verify the signature against known authorities.

1 comments

You can make a JWT invalid after 30 seconds or even 1 second. You should set an aud (audience) when creating the JWT. Otherwise the signature is crypto-graphically sound. Validate every single JWT every single time with a short lifetime.

OIDC tokens are all JWTs btw.

If your talking about a browser context, where the authority is separate from the requesting body, then expiring even at 30s is excessive for user context, let alone every 1s or every request... you're effectively then inflating every single API request into 2 requests... one for a new token, then another to the API being called. This is irresponsible for not much gain in a user-facing context.
You should not be using them for user contexts at all. The cookie should be the session token and the sessions should be stored on the server side where you can simply delete them and the user's login becomes invalid. Using JWTs for this use case is just plain wrong.