A Windows box with network discovery on — WSD's HTTP endpoint for printers, scanners, and device metadata.
5357 is Microsoft's wsdapi port: the HTTP transport for Web Services on Devices, the stack behind WSD printing and scanning and behind Windows' Function Discovery Resource Publication service. Devices are found first over WS-Discovery multicast on UDP 3702, then queried for metadata and driven over HTTP here, with 5358 as the HTTPS variant. It opens automatically on Windows hosts and on network printers and NAS boxes whenever the network profile is Private, so it is one of the most common open ports on a Windows LAN.
Do not expose
It is an unauthenticated LAN discovery service that hands out device and host metadata, and WSDAPI has had remotely reachable code-execution bugs — keep it off any public interface.
$ curl -sS -o /dev/null -w '%{http_code}\n' http://TARGET:5357/Seen this on your network? Beige Box scans your Wi-Fi and shows every open port on every device — and its Ports tool links straight back here.
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Corrections or a missing port? Reply @rimrocksystems.