Package Instance

Improper Authentication
In wolfSSL before 5.2.0, a TLS 1.3 server cannot properly enforce a requirement for mutual authentication. A client can simply omit the `certificate_verify` message from the handshake, and never present a certificate.

Improper Certificate Validation
If a TLS 1.3 client gets neither a PSK (pre shared key) extension nor a KSE (key share extension) when connecting to a malicious server, a default predictable buffer gets used for the IKM (Input Keying Material) value when generating the session master secret. Using a potentially known IKM value when generating the session master secret key compromises the key generated, allowing an eavesdropper to reconstruct it and potentially allowing access to or meddling with message contents in the session. This issue does not affect client validation of connected servers, nor expose private key information, but could result in an insecure TLS 1.3 session when not controlling both sides of the connection. wolfSSL recommends that TLS 1.3 client side users update the version of wolfSSL used.

Improper Certificate Validation
In wolfSSL before 5.2.0, certificate validation may be bypassed during attempted authentication by a TLS 1.3 client to a TLS 1.3 server. This occurs when the `sig_algo` field differs between the `certificate_verify` message and the certificate message.

Improper Handling of Exceptional Conditions
wolfSSL does not produce a failure outcome when the serial number in an OCSP request differs from the serial number in the OCSP response.

Insufficient Verification of Data Authenticity
wolfSSL incorrectly skips OCSP verification in certain situations of irrelevant response data that contains the NoCheck extension.