CWE-347

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 verify function in the Stark Bank Elixir ECDSA library (ecdsa-elixir) 1.0.0 fails to check that the signature is non-zero, which allows attackers to forge signatures on arbitrary messages.

The verify function in the Stark Bank .NET ECDSA library (ecdsa-dotnet) 1.3.1 fails to check that the signature is non-zero, which allows attackers to forge signatures on arbitrary messages.

The verify function in the Stark Bank Java ECDSA library (ecdsa-java) 1.0.0 fails to check that the signature is non-zero, which allows attackers to forge signatures on arbitrary messages.

The verify function in the Stark Bank Node.js ECDSA library (ecdsa-node) 1.1.2 fails to check that the signature is non-zero, which allows attackers to forge signatures on arbitrary messages.

The verify function in the Stark Bank Python ECDSA library (aka starkbank-escada or ecdsa-python) before 2.0.1 fails to check that the signature is non-zero, which allows attackers to forge signatures on arbitrary messages.