Jwt.io JSON parse error?

Hello all,

I’m sorry if this was posted before, I could not find it using the search function.

My issue is I am trying to create a JWK using ES256. To the best of my knowledge I have base-64-url-safe-encoded the header and payload, with the appropriate base-64-url-safe-encoded curve points of x and y. I have also created the signature using concatenation of r and s from ECDSA signing and base-64-url-safe-encoded them as well. I then concatenate then all together in the appropriate xxx.yyyy.zzz format.

However, when I try to validate the JWT on jwt.io, it gives me An array of 3 errors, an SPKI error, ad x.509 error, and an “unexpected end of JSON” JSON parse error. The inputs appear to be correct for the header and payload, and I have validated the output as properly formatted JSON on separate websites, so I am at a dead-end on the source of the issue.

If anyone has any advice I would appreciate it, and if code is necessary I can supply some early tomorrow.

1 Like