Under specific condition, .NET 7 and 8 are leaking native memory during TLS handshake. The specific condition is:

• Server sends OCSP staple during TLS handshake (server running .NET 7+, or other stacks supporting OCSP)
• A client certificate is used and supplied via LocalCertificateSelectionCallback to SslStream:
  • This is the behavior for HttpClient configured with HttpClientHandler (the default handler)
  • Alternative ways do not have the problem (SslClientAuthenticationOptions.ClientCertificatesCollection or SslClientAuthenticationOptions.ClientCertificateContext)
• Server performs renegotiation (or post-handshake client authentication)