joaquimserafim/json-web-token is a javascript library use to interact with JSON Web Tokens (JWT) which are a compact URL-safe means of representing claims to be transferred between two parties. Affected versions of the json-web-token library are vulnerable to a JWT algorithm confusion attack. On line 86 of the index.js file, the algorithm to use for verifying the signature of the JWT token is taken from the JWT token, which at that point is still unverified and thus shouldnt be trusted. To exploit this vulnerability, an attacker needs to craft a malicious JWT token containing the HS256 algorithm, signed with the public RSA key of the victim application. This attack will only work against this library is the RS256 algorithm is in use, however it is a best practice to use that algorithm.
The product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Json_web_token | Joaquimserafim | * | 3.1.1 (excluding) |