python-cryptography: NULL pointer dereference with pkcs12.serialize_key_and_certificates when called with a non-matching certificate and private key and an hmac_hash override

A flaw was discovered in python-cryptography. A NULL pointer dereference can be triggered when a PKCS12 key and certificate do not match. Specifically, if the pkcs12.serializekeyandcertificates function is called with a non-matching certificate and private key and an encryption algorithm with...