When CURLOPT_PINNEDPUBLICKEY is configured alongside options that disable
standard peer verification (CURLOPT_SSL_VERIFYPEER = 0 and
CURLOPT_SSL_VERIFYHOST = 0), libcurl fails to enforce public key pinning on
connections established without a presented server certificate. Bypassing the
pinning check under these disabled-verification conditions allows
unauthenticated connections to succeed when they should be rejected.