Http2 Pri Asterisk Probe

A request using the PRI method targeting * (for example PRI * HTTP/2.0), which represents the HTTP/2 connection preface being sent over a cleartext HTTP endpoint. This primitive indicates low-level protocol probing where a scanner tests HTTP/2 support or observes how the service handles unexpected method–target combinations. When seen on Elasticsearch-exposed ports, it reflects generic transport fingerprinting rather than legitimate Elasticsearch API interaction.