How to prevent replay attacks with JWT token?
When using JWT, we can use the exp claim to expire the token after a specific time. This, combined with the jti claim is useful to prevent replay attacks, and something that will be built in to our app. However, for user convenience, we do not want to keep asking them to log in with every request or after short intervals of say, 30 minutes.
How to protect JWT on the client side?
Protecting the JWT on the client side is the job of the application using the JWT, not the API. If this line is blurred than you may need to re-engineer you application as it’s probably more monolithic, rather than service driven. JTI, EXP and IAT are designed more to give you the tools to mitigate an attack if it’s been compromised.
Can a man in the middle attack on JWT?
You’re absolutely correct about your concern of a man-in-the-middle attack: if someone DOES intercept the JWT (and its single-use JTI) and then makes a request BEFORE you do, their request will be considered valid and YOUR subsequent requests will appear to the server to be “replays” (and the server would consider them invalid).
How to prevent resubmission and replay attack using client?
The backend server checks the JWT and executes the request. The current issue is, anyone who can intercept the HTTP package can replay the API call. Moreover, in the situation with a bad network, the client may press the submit/confirm button twice and resubmit the request.
How to properly use JTI claims with JWT?
Implementing a JTI to uniquely identify a JWT can help prevent replay attacks where an attacker sends the same JWT to make a request. The server would generate the JTI value and send it along with a new JWT on every response.
Is there a way to prevent replay attacks?
This also doesn’t outright prevent replay attacks, but it can shut down further such attacks after one has been detected. An alternative/additional method CAN outright prevent replay attacks to some degree, at the risk of potential inconvenience to the user.
What happens if a JWT key is leaked?
Having a leaked private key would be equivalent to issuing JWTs using only the header and payload sections, and trusting any such JWT a user sends you. If the private key isn’t private, there’s no protection offered by the signature section anymore, so you might as well leave it off.
When to use JWT to avoid CSRF attack?
If session-id matches and the timestamp is under the defined token expiry time, the request is allowed. based on the fact that CSRF is only possible if the authentication cookie was sent along with the forged request, we can use JWT authentication to avoid CSRF attack.