JWT token is malformed, spring boot

Question

I am configuring jwt into my spring boot project. The jwt token is generated with the username

public String generateTokenFromUsername(String username) {
    return Jwts.builder().setSubject(username).setIssuedAt(new Date())
            .setExpiration(new Date((new Date()).getTime() + jwtExpirationMs)).signWith(SignatureAlgorithm.HS256, jwtSecret)
            .compact();
}
public String generateJwtToken(UserDetailsImpl userPrincipal) {
        logger.info(userPrincipal.getUsername());
        return generateTokenFromUsername(userPrincipal.getUsername());
    }

I am able to successfully register a user however when it is parsed by the validation method

        Jwts.parser().setSigningKey(jwtSecret).parseClaimsJws(authToken);

The complete validation method:

 public boolean validateJwtToken(String authToken) {
    try {
        Jwts.parser().setSigningKey(jwtSecret).parseClaimsJws(authToken);
        return true;
    } catch (SignatureException e) {
        logger.error("Invalid JWT signature: {}", e.getMessage());
    } catch (MalformedJwtException e) {
        logger.error("Invalid JWT token: {}", e.getMessage());
    } catch (ExpiredJwtException e) {
        logger.error("JWT token is expired: {}", e.getMessage());
    } catch (UnsupportedJwtException e) {
        logger.error("JWT token is unsupported: {}", e.getMessage());
    } catch (IllegalArgumentException e) {
        logger.error("JWT claims string is empty: {}", e.getMessage());
    }

It throws back a malformed error

Invalid JWT token: Unable to read JSON value: �z��&�r#�$�3S"

This is a sample json response from postman:

{
"accessToken": "eyJhbGciOiJIUzUxMiJ9.eyJzdWIiOiJsdWN5MjEiLCJpYXQiOjE2NDI0NTM4NjQsImV4cCI6MTY0MjU0MDI2NH0.Kynh2wIDCoQD6spaA4q5Q7z4F6l5TL6CXJQ_dqNYZqRl5zoBArubLoIFrphXfC4iB9qY2UfdcW9vU_MI0WB9SA",
"type": "Bearer",
"refreshToken": "3deb73e2-a31f-43de-9423-4a561978e506",
"id": "9e7a208d-770b-4395-b2a3-255d72d59518",
"name": "John Doe",
"email": "lucy21",
"role": [
    "READER"
]}

I don't know where the error is generated from. Could anyone please help?

As error says there is problem with parsing json. But where are you using json? you can pass token in header and handle it in interceptor — Yrysbek Tilekbekov, Jan 17 '22 at 07:16
@TilekbekovYrysbek the response sent to post is json. The error is thrown when a user registers. — Sommy, Jan 17 '22 at 23:26
I have added a sample json response from postman after registering a user — Sommy, Jan 17 '22 at 23:30
Please, all you have posted is single methods, where is tour security setup, rest endpoints? Please provide an actual working example and not just singel methods — Toerktumlare, Jan 18 '22 at 07:29

score 0 · Answer 1 · answered May 03 '23 at 14:39

0

In my case the error io.jsonwebtoken.MalformedJwtException: Unable to read JSON value: ?z&?r#$3#Sb was related to a simple mistake: instead of a token itself "eyJhbGc..." JWT was trying to decode token with Bearer prefix: "Bearer eyJhbGc....".

answered May 03 '23 at 14:39

Shalguev

81
3

JWT token is malformed, spring boot

1 Answers1