178
Summary
- // if you see it open
- No CVE, malware, or trojan association documented in GRC Port Authority Database or nmap-services. An open 178/tcp on a modern host is unusual — likely a legacy artifact or a custom service reusing the name, not a recognizable active standard protocol.
- // analyst note
- essentially unused in current scanning data; treat an open port 178 as a legacy artifact or a reused/custom service rather than an active NeXTSTEP host.
About port 178/tcp.
Port 178/tcp is registered with IANA under the service name nextstep, described as "NextStep Window Server," with assignee and contact Leo Hourvitz and a blank Reference field — no RFC or other formal specification is cited for this assignment. The registry entry is dual-registered: 178/udp carries the identical service name, description, and assignee, which is typical of legacy-era IANA registrations that reserved a port number across both transports without necessarily implying an active UDP-side protocol. The assignment traces to NeXT, Inc., the company Steve Jobs founded after leaving Apple, whose NeXTSTEP operating system ran on NeXT workstations in the late 1980s and early 1990s and later became the technical basis for OPENSTEP and, eventually, macOS. The "Window Server" in the name refers to the display/windowing subsystem of NeXTSTEP, which used a Display PostScript-based architecture; a network port here is consistent with remote or inter-process window-server communication in that environment, though no protocol specification is on record to confirm wire-level details. No IANA registration or modification date is recorded for this entry, and none is invented here. In current internet-facing practice this port is essentially unused: scan-frequency data places it far below any actively deployed service, and no modern software, malware family, or CVE is documented as using port 178. An analyst encountering an open 178/tcp today should treat it as either a legacy artifact, a custom service reusing an old port number, or worth manual investigation rather than assuming a recognizable standard protocol.
- IANA assignment
nextstep— "NextStep Window Server"; reference (blank — no RFC cited in IANA registry); assignee/contact Leo Hourvitz; dual-registered 178/tcp + 178/udp with identical content [Confirmed] — https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml- Range class
- well-known (0–1023) [Confirmed] — https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml
- Registration/modification dates
- not recorded in the IANA registry entry; reported as Unknown rather than fabricated [Confirmed] — https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml
- Prevalence
- nmap-services open-frequency 178/tcp ≈ 0.000000 (essentially never observed open); 178/udp ≈ 0.000346 (very rare) [Confirmed] — https://svn.nmap.org/nmap/nmap-services
- Related ports
- no directly adjacent registered cluster identified; contrast with other legacy vendor-specific well-known assignments
Primary use
registered name only ("nextstep"); historically associated with NeXT, Inc.'s NeXTSTEP Display PostScript-based Window Server for the NeXT operating system; no RFC defines a wire protocol
Security implications
no CVE, malware, or trojan association found in GRC Port Authority Database or nmap-services; an open 178/tcp on a modern host is unusual and should be treated as legacy, custom, or worth investigation
Typically seen on
legacy NeXT/NeXTSTEP workstations (historical); otherwise an anomaly on modern networks
- Current software
- no actively maintained software documented as using port 178 today; historical association only with NeXT hardware/software from the ~1990s [Likely] — https://www.grc.com/port_178.htm
- Analyst note
- essentially unused in current scanning data; treat an open port 178 as a legacy artifact or a reused/custom service rather than an active NeXTSTEP host.
About port 178/udp.
Port 178/udp is IANA-registered as nextstep, described simply as "NextStep Window Server," with Leo Hourvitz listed as both assignee and contact. The registry carries no registration date, no modification date, and no RFC or other reference for this entry — those fields are blank in the canonical IANA CSV, not merely uncaptured, so nothing is inferred to fill them. The assignment is dual-registered: 178/tcp holds an identical row (same service name, same description, same assignee/contact, same blank metadata), which is typical of NeXT-era registrations from the late 1980s. Functionally, the port names the network protocol used by the NeXTSTEP Window Server, the display and windowing subsystem of NeXT Computer's NeXTSTEP operating system and its later OPENSTEP lineage — hardware and software that saw use roughly from the late 1980s through the 1990s and is effectively extinct in production today. No current or maintained software was found still binding to 178/udp for its registered purpose, and standard trojan/backdoor port references (Trend Micro, Gary Kessler's Bad Ports list, common Snort malware-backdoor rulesets) show no association with this port. No internet-scan telemetry was found quantifying real-world exposure. On a 2026 network, a live NeXTSTEP host is implausible, so observed 178/udp activity more plausibly reflects scan noise, spoofing, or misconfiguration than a genuine service.
- IANA assignment
nextstep— "NextStep Window Server"; assignee/contact Leo Hourvitz; registration date, modification date, and reference fields blank in registry [Confirmed] — the IANA Service Name and Transport Protocol Port Number Registry (IANA cached registry) and https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xml- Dual registration
- 178/tcp carries an identical row (same service name/description/assignee/contact, same blank metadata) [Confirmed] — the IANA Service Name and Transport Protocol Port Number Registry
- Range class
- well-known (0–1023)
- IANA reference/RFC
- none listed — left blank, not fabricated [Confirmed] — https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xml
Primary use
networking protocol for the NeXTSTEP Window Server, the display/windowing subsystem of NeXT Computer's NeXTSTEP OS and later OPENSTEP lineage, used roughly late 1980s–1990s
Malware/trojan association
none found in standard references (Trend Micro Trojan Ports, Gary Kessler's Bad TCP/UDP Ports List, common Snort malware-backdoor ruleset) [Confirmed] — https://docs.trendmicro.com/all/ent/officescan/v10.5/en-us/osce_10.5_olhcl/osce_topics/what_are_trojan_ports_.htm, https://www.garykessler.net/library/bad_ports.html, https://github.com/John-Lin/docker-snort/blob/master/snortrules-snapshot-2972/rules/malware-backdoor.rules
Exposure/scanning prevalence
no sourced scan telemetry (Shodan/Censys/SANS ISC or similar) found quantifying real-world exposure
- Current usage
- no maintained software found still using 178/udp for its registered purpose; NeXTSTEP/OPENSTEP systems are effectively extinct in production [Likely] — no citable source found (absence-based)
- Security posture
- legitimate open 178/udp is not expected on modern (2026) infrastructure given the defunct host OS; observed traffic more plausibly scan noise, spoofing, or misconfiguration [Likely] — inference from registry + absence of current-usage evidence
Service assignments.
| Name | Protocol | Description | Open frequency |
|---|---|---|---|
| nextstep | UDP | NextStep Window Server | 0.03% |
| nextstep | TCP | NextStep Window Server | 0.00% |
Service assignments from the IANA Service Name and Transport Protocol Port Number Registry, with open-frequency data from nmap-services.