Unassigned on TCP and UDP, part of the 27352-27356 cluster of unnamed scan hits.
27355 is inside IANA's unassigned range 27346-27441 and has no registration. Nmap carries 'unknown' entries for it on both TCP and UDP. Its open-frequency matches its neighbours 27352, 27353 and 27356 closely enough that the four are effectively one scanning artefact rather than four distinct services. Nothing verifiable identifies what answers.
Expose with care
Treat as an unknown listener. A version scan is the only thing that turns this into a real verdict.
$ nmap -Pn -sV -p 27355 --reason TARGETSeen 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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