CVE-2022-23540: jsonwebtoken vulnerable to signature validation bypass due to insecure default algorithm in jwt.verify()

A flaw was found in the jsonwebtoken library. In affected versions of the jsonwebtoken library, lack of algorithm definition and a falsy secret or key in the jwt.verify() function may lead to signature validation bypass due to defaulting to the none algorithm for signature verification.

Auth0 jsonwebtoken could allow a remote authenticated attacker to bypass security restrictions, caused by an insecure default algorithm flaw in the jwt.verify() function. By sending a specially-crafted request, an attacker could exploit this vulnerability to bypass signature validation.

— IBM

In versions <=8.5.1 of jsonwebtoken library, lack of algorithm definition in the jwt.verify() function can lead to signature validation bypass due to defaulting to the none algorithm for signature verification. Users are affected if you do not specify algorithms in the jwt.verify() function. This issue has been fixed, please update to version 9.0.0 which removes the default support for the none algorithm in the jwt.verify() method. There will be no impact, if you update to version 9.0.0 and you don’t need to allow for the none algorithm. If you need 'none' algorithm, you have to explicitly specify that in jwt.verify() options.