If an OpenID Connect provider supports the none algorithm (i.e., tokens with no signature), pac4j v5.3.0 (and prior) does not refuse it without an explicit configuration on its side or for the idtoken response type which is not secure and violates the OpenID Core Specification. The none algorithm does not require any signature verification when validating the ID tokens, which allows the attacker to bypass the token validation by injecting a malformed ID token using none as the value of alg key in the header with an empty signature value.
The product does not verify, or incorrectly verifies, the cryptographic signature for data.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Pac4j | Pac4j | * | 4.5.5 (excluding) |
| Pac4j | Pac4j | 5.0.0 (including) | 5.3.1 (excluding) |