The last of the low dynamic ports scanners bother to probe by default.
49157 sits in the never-assigned dynamic range and, like its neighbours, is normally a Windows RPC endpoint handed out at service start. It is the tail of the block Nmap keeps in its default scan set, open on about 0.36% of hosts — less often than 49152 because fewer machines allocate that many endpoints. Anything above it in the range is scanned only when you ask for it explicitly.
Do not expose
Same rule as the rest of the range: internal only, and pin services to static ports if you genuinely need a narrow firewall rule.
$ nmap -sV -Pn -p 49157 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.
Get Beige Box →also available as JSON · Markdown
Corrections or a missing port? Reply @rimrocksystems.