RUSTSEC-2026-0336 MIKEY message MAC is never verified on receive, so forged messages are accepted

mykey implements MIKEY RFC 3830 for SRTP key exchange. No receive path verified the MIKEY message authentication code. crypto::verifymac existed and was correct, but it was called only from unit tests — neither MikeyMessage::frombytes nor MikeyMessage::completepsk invoked it. newpskinit computed ...