True, the implementations were lacking some finesse. But a proper keychain type cert store handled by the operating system should in theory be able to protect t

True, the implementations were lacking some finesse. But a proper keychain type cert store handled by the operating system should in theory be able to protect the certificate against usermode malware (perhaps by only coughing up the certificate to an application signed with the same code signing ID as the application that inserted the certificate, and/or after an elevated password prompt)