432

Port 432/tcp carries no documented protocol beyond a bare IANA registration for the service name iasd ("IASD"); no software, vendor, or specification has ever been tied to it, so it has no established legitimate reason to be reachable from the public internet, and a live listener should be treated as an anomaly rather than trusted.

IANA's service-names-port-numbers registry dual-registers 432 to iasd on both TCP and UDP, with Description "IASD" and Assignee/Contact both listed as Nir Baroz. The Reference, Registration Date, and Modification Date columns are all blank — no RFC or standards document backs the assignment, and no filing date is on record for either transport.

No expansion of "IASD" appears in any RFC or vendor specification. An August 2026 search across vendor documentation, blog posts, forum and support threads, and game/P2P client references found no software confirmed to use this port. Port-lookup aggregator sites (SpeedGuide, t1shopper, adminsub.net, AuditMyPC, windows9download) only mirror the bare IANA line without adding independent sighting or deployment detail.

nmap-services' open-frequency sampling puts 432/tcp at roughly 0.0013% (0.000013) and 432/udp at about 0.058% (0.000577) — real sampled readings, not absences, and both consistent with a port that almost never turns up open. No CVE, named malware family, or documented Trojan/RAT is recorded against either transport as of an August 2026 search.

IANA assignment

iasd — description "IASD"; Reference blank (no RFC cited); Assignee and Contact both Nir Baroz; dual-registered 432/tcp + 432/udp [Confirmed] — the IANA Service Name and Transport Protocol Port Number Registry iasd 432/tcp

Range class

well-known (0–1023) [Confirmed] — the IANA Service Name and Transport Protocol Port Number Registry iasd 432/tcp

Prevalence

nmap-services open-frequency 432/tcp ≈ 0.000013 (~0.0013%); 432/udp ≈ 0.000577 (~0.058%) — real sampled readings, not absences [Confirmed] — this site's own tooling

Related ports

430/tcp+udp utmpsd and 431/tcp+udp utmpcd — adjacent, similarly undocumented individual reservations in the same registry block; 433/tcp+udp nnsp is unrelated, an actively documented protocol (NNTP for transit servers, RFC 3977)

[Confirmed] — the IANA Service Name and Transport Protocol Port Number Registry utmpsd 430/tcp, utmpcd 431/tcp, nnsp 433/tcp

Primary use

Unknown — no RFC, specification, or documented protocol behavior exists for "iasd" beyond the bare registry label

Other/unofficial uses

none identified — an August 2026 search of vendor docs, blogs, forum/support threads, and game/P2P client references found no software confirmed to use this port [Unknown]

Security implications

no CVE recorded in the NVD as of 2026-08; no credible malware/trojan association found as of an August 2026 search; not cited in mainstream scanning/attacked-port writeups

Typically seen on

no confirmed hosts or products; the registration is a personal 1990s-era assignment with no documented deployment [Unknown]

Analyst note

An open 432/tcp has no confirmed legitimate use — treat it as anomalous, a possible decoy, or grounds to fingerprint the responding host/application directly rather than assuming a known service.

Port 432/udp is registered with IANA under the service name iasd (description "IASD"), but no RFC, public protocol specification, or confirmed real-world software has ever been identified using it. With no established legitimate purpose, an open 432/udp should be treated as unusual and kept off the public internet rather than assumed to be routine or safe.

The registration carries a blank Reference field and lists Nir Baroz as assignee, with no registration or modification date recorded. The name iasd is dual-registered on both TCP and UDP at port 432 — a common pattern for early IANA entries that reserved a port pair without necessarily building or documenting both transports.

No community-sourced sighting of specific client or server software using 432/udp turned up despite an active search of vendor and aggregator port-lookup sites as of an August 2026 search; several target pages returned no data or were unreachable. No CVE or malware family is verifiably tied to this port either, though one low-quality aggregator's citation needed correcting (see Security).

IANA assignment

iasd — "IASD"; reference (blank — no RFC cited in IANA registry); assignee Nir Baroz; dual-registered 432/tcp + 432/udp [Confirmed] — the IANA Service Name and Transport Protocol Port Number Registry iasd 432/udp

Range class

well-known (System Ports, 0–1023) [Confirmed] — IANA Service Name and Transport Protocol Port Number Registry

Prevalence

nmap-services open-frequency 432/udp = 0.000577 (~0.058%); 432/tcp = 0.000013 (~0.001%) [Confirmed] — this site's own tooling

Related ports

432/tcp (same iasd service name, dual-registered) [Confirmed] — the IANA Service Name and Transport Protocol Port Number Registry iasd 432/tcp

Primary use

undocumented beyond the bare registration name; no RFC, protocol specification, or confirmed real-world software identified

Other/unofficial uses

none found; checked community/vendor port-lookup aggregators as of an August 2026 search with no credible sighting returned

Security implications

no CVE or malware family verifiably tied to this port; a third-party aggregator's attribution of CVE-2008-3269 and CVE-2017-11502 to port 432 is incorrect (both concern TCP port 4321, not 432); auditmypc.com's scan verdict reads "Virus/Trojan: No" [Confirmed] — https://www.auditmypc.com/udp-port-432.asp, https://nvd.nist.gov/vuln/detail/CVE-2008-3269, https://nvd.nist.gov/vuln/detail/CVE-2017-11502

Typically seen on

Unknown — no confirmed deployment context found as of an August 2026 search of IANA and community port-lookup sources

Analyst note

An open 432/udp has no established legitimate purpose in available research; treat it as anomalous, verify what is actually listening, and do not assume it is safe or expected traffic.