Questions tagged [jwt]
JWT specifies JSON web tokens. It is defined in RFC 7519: JSON Web Token (JWT)
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How to verify that a JWT was in fact generated by the claimed issuer (iss)?
JSON Web Tokens (JWTs) (RFC, introduction) are digitally signed using a secret key (which can be symmetric, but for distributed use cases will typically be asymmetric). The signature forms the third ...
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best HMACSHA signed JWT secret length
I would like to use JWT but one thing I'm still thinking is ¿what is the best length for the secret?
If I'm using HS512 as a signing method the secret should have a length of 512 bits as far as I ...
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is this how RS256 works in JWT?
I'm a newbie that is studying about JWT using RS256 algorithm for signing and verification. I have drawn a diagram that represents my understanding of how RS256 works.
Basically, below is what I ...
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Fusion auth versus jose4j library for jwt using secp256k [closed]
I am a beginner in-terms of JWT libraries in programming.
How the keypair used (secp256k1) is related with the algorithmic header used for creation of JWT?
And why authfusion doesn't need an ...
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How to exchange keys in JWT between server and client and between shared servers?
I'm not sure I have a full understanding of JWT when it comes to the signature. The signature, as I get it, validates to the server that the header/payload that was transfer from the client is legit.
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What is the proper format/ notation for JSON Web Tokens?
A JSON Web Token is supposed to have the following format:
token = encodeBase64(header) + '.' + encodeBase64(payload) + '.' + encodeBase64(signature)
When I use ...
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Is it secure to sign a JWT using RS256?
I have implemented an authentication scheme using JWT with assymetric keys (RS256). The idea is that (assuming some microservice-based acrhitecture) the authentication service will sign all JWTs with ...
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If I sign-then-encrypt a JWT, how does a 3rd party validate that the JWE message is valid?
Since it is preferred to sign-then-encrypt I was wondering how can another party validate that the message is valid?
The use case I had was the following...
Client authenticates and gets the access ...
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A way to get the public key of a RS256 JWT from its headers and payload?
I have a RS256 JWT, I'd like to find out its public key. Because I know the header, payload and I have the encrypted signature, is there a way to obtain the public key that made the signature from ...
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Does the signature length of RS256 depend on the size of the RSA key used for signing?
The following NodeJS code, when run (v16.8.0), logs 512 to stdout.
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Match any string from list to a single hash
This might be a noob question, I've searched the web but couldn't find anything remotely close to what I would like to achieve. Maybe I don't have the correct jargon, so please bear with me.
Basically,...
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Securely transmit signed token (e.g., JWT) over insecure channel
Apologies if this is already answered somewhere, but I could not find it.
I have a setup where a client has a JWT (RSA- or ECDSA-signed), and needs to prove that fact to the peer which issued the ...
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How can JWE support an integrity check given that it uses a public key to encrypt the message?
As far as I know JWE (JSON Web Encryption) supports both integrity and confidentiality. I agree about the confedintiality because only the recepient with a private key can decrypt a message. What ...
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Which Cryptographic Standard ensures cryptographic agility and good adapotion
Which cryptographic message standards are recommended to ensure cryptographic agility in the future and have good adoption trough different programming languages such as .NET and Go?
The standard ...
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How many JWT tokens may be securely generated with one secret?
I can remember from my crypto classes, that there is a limit on how many blocks can be securely encrypted with the same key. Before we reach the limit, we should rotate the key. Does it also hold true ...
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What is a "set synchronized CSPRNG"?
I'm looking to implement a performant revocation method for JWTs. I'm reading a paper, in which the following section's second paragraph states:
If we use the client hashing approach described ...
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How RSA is implemented by authentication protocols?
I am a beginner in cryptography, i recently learned about RSA algorithm : In short, my understanding for this is :
Sender needs receiver's public key to encrypt the message to a cipher so that only ...
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Validating JWT works with small changes to public key, why?
I was trying to verify the following JWT on JWT.io with the following public key:
...
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JWTs vs Capability Tokens
One of the primary advantages of JWTs is that they serve as capability tokens, allowing for a portable verification of capabilities/ privileges. However, JWTs are often criticized for a number of ...
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Are there any security drawbacks for simply encrypting and MACing my JWS token (JWT)?
This question, while related, doesn't answer the security aspect I have in mind. I understand that signatures make it impossible for the tokens to be modified. But if I want the JWS token content to ...
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JWT Login Security
I am new to security and I am wondering if JWT is secure enough.
From what I have read online the flow goes like this:
Clients log in by sending their credentials to the identity
provider.
The ...
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Base64 encoding of strings
I have read everywhere that base64 encoding of unique binary/hex values results in unique output. The following two string encode to virtually the same output.
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How can one validate with a public key a JWT signature generated with a private key?
As I understand it, a JSON Web Token (JWT) consists of 3 parts:
the header, specifying the hashing algorithm to use for the signature;
the payload itself; and
the signature, which is a hash of the ...
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AES-CBC then SHA vs AES-GCM for encrypting and authenticating a web token
I am trying to have something like JWT but kinda ad hoc and encrypted. The token itself is simply a stringified JSON that contains the user ID and Unix timestamp.
Now, I tried to use AES-128-GCM, ...
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Is symmetric encryption with a key containing the userId passes as authentication?
The scenario:
There is a web application where ownership check is time expensive so during the development all users were able to access all other user's objects (let's say apples) by changing the ...
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HMAC-SHA256 vs HMAC-SHA512 for JWT API authentication
Which algorithm is recommended to use when encoding / decoding JWT web application tokens? Is using HMAC-SHA256 enough or would using ...
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sign data and append certificate VS sign data and certificate
I am currently writing my masters thesis in which I need to develop a licensing module for an application.
The license itself is a JSON Web Token which is signed using a RSA private key.
Since we ...
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JWT Common Practices
I had a few questions in regards to certain practices used by JWT developers.
I'm relatively new to both encryption and JWTs and the context given is for developing a system on nodejs.
How should ...
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Compromise between HMAC and Digital Signature, by encrypting and sending secret key?
For achieving stateless authentication tokens (like JWT), is there a compromise between the performance of HMAC, and public key distribution of Digital Signature?
Scenario:
Sender is a centralized ...
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HMAC vs ECDSA for JWT
I will be implementing JSON web tokens into my website and have a question about implementing them. I have a choice of using two algorithms, HMAC-SHA256 and ECDSA-SHA256. I have used HMAC-SHA256 in ...
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what are the advatanges and disavantages of the digital signature algorithms for JWT?
I am using a Java JWT library jose4j.
There is a list of digital signatures algorithms which can be used.
HMAC using SHA-2
RSASSA-PKCS1-V1_5 Digital Signatures with with SHA-2
Elliptic Curve Digital ...
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Padding to increase entropy and size of (otherwise) small JSON objects
Maybe this better fits, the security stackexchange...
I'm building a web API. We want to enable some relatively simple encryption, instead of going full-blown OAuth2 (which frankly, IMO, sucks). So I ...
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