The Go project reports: crypto/x509: usage of IPv6 zone IDs can bypass URI name constraints A certificate with a URI which has a IPv6 address with a zone ID may incorrectly satisfy a URI name constraint that applies to the certificate chain. net/http: sensitive headers incorrectly sent after cross-domain redirect The HTTP client drops sensitive headers after following a cross-domain redirect. For example, a request to a.com/ containing an Authorization header which is redirected to b.com/ will not send that header to b.com.