Affected versions of the jws package allow users to select what algorithm the server will use to verify a provided JWT. A malicious actor can use this behaviour to arbitrarily modify the contents of a JWT while still passing verification. For the common use case of the JWT as a bearer token, the end result is a complete authentication bypass with minimal effort.

Recommendation

Update to version 3.0.0 or later.

References

• auth0/node-jws@585d0e1#diff-4ac32a78649ca5bdd8e0ba38b7006a1e
• https://auth0.com/blog/2015/03/31/critical-vulnerabilities-in-json-web-token-libraries/
• https://www.npmjs.com/advisories/88
• https://nvd.nist.gov/vuln/detail/CVE-2016-1000223
• https://snyk.io/vuln/npm:jws:20160726