529

Port 529/tcp is registered with IANA under the name irc-serv for an IRC-related server service, but no confirmed real-world software implementation was found and the port shows zero measured open-port prevalence, so it should not be expected on the public internet — a live listener here is worth investigating rather than trusting as routine IRC traffic.

The IANA Service Name and Transport Protocol Port Number Registry lists 529 as dual-registered on both TCP and UDP under irc-serv, description "IRC-SERV," assignee and contact Brian_Tackett. The Reference, Registration Date, and Modification Date fields are all blank, meaning no RFC or dated record backs this assignment.

This is distinct from the well-known IRC client/server ports (6667, 6697, and similar), which handle the vast majority of real-world IRC traffic. A web search for vendor documentation, blog posts, or forum threads describing software that actually binds to 529/tcp turned up only generic port-lookup aggregator pages restating the bare IANA entry; one aggregator speculated that servers like InspIRCd or UnrealIRCd "might" use it, but neither project's official documentation references port 529, so that guess is not treated as a sighting.

Exposure

Registered under IANA but with no known real-world software implementation, a blank RFC reference, and zero measured open-frequency — treat any observed listener on 529/tcp as anomalous and worth investigating rather than assuming legitimate IRC service.

Malware association

No credible malware or trojan association was found for 529/tcp as of an August 2026 search; an attempted auditmypc.com check did not return retrievable content, so no claim (positive or negative) is made from that source.

IANA assignment

irc-serv — "IRC-SERV"; reference (blank); assignee Brian_Tackett; dual-registered 529/tcp + 529/udp [Confirmed] — the IANA Service Name and Transport Protocol Port Number Registry irc-serv 529/tcp

Range class

system/well-known (0–1023) [Confirmed] — the IANA Service Name and Transport Protocol Port Number Registry irc-serv 529/tcp

Prevalence

nmap-services open-frequency 529/tcp = 0.0 (sampled, not observed open) [Confirmed] — this site's own tooling (port 529, tcp)

Related ports

529/udp (identical registration); mainstream IRC ports 6667/6697 for contrast

Primary use

IANA-registered IRC-related server service; no RFC defines it and no confirmed software implements it

Other/unofficial uses

none documented; distinct from mainstream IRC ports 6667/6697

Security implications

no NVD CVE found; no confirmed malware association; blank IANA reference and zero measured prevalence make any live listener anomalous

Typically seen on

not documented as typically seen anywhere; a registered but essentially unused port [Unknown]

Analyst note

A registered-but-undeployed port with zero measured prevalence; treat an open 529/tcp as a fingerprinting or anomaly signal rather than expected IRC service, and investigate before assuming legitimacy.

Port 529/udp carries no verified production service; it is a rarely used IANA registration named irc-serv with essentially no observed real-world traffic, so it should not be treated as a legitimate active service and any activity found on it deserves scrutiny rather than an assumption of normal use.

The IANA Service Name and Transport Protocol Port Number Registry lists 529 as dual-registered on both TCP and UDP under the name irc-serv, described only as "IRC-SERV," assigned to Brian Tackett, with a blank Reference field — no RFC or formal specification documents an actual wire protocol for this assignment.

The nmap-services corpus records an open-frequency of about 0.000544 (roughly 0.05%) for 529/udp, distinct from the 529/tcp entry which samples at exactly 0. Both figures indicate the port is almost never found open in scanned populations, consistent with the absence of any documented deployment.

No vendor documentation, blog post, or forum thread was found describing software that actually generates traffic on 529/udp, and no CVE is recorded against it as of an August 2026 search. Generic port-lookup aggregator sites restate the bare IANA registration without adding independently verified detail.

Given the name, the port is presumably intended for something IRC-server-adjacent, but production IRC deployments use other registered ports — 194/tcp is registered as irc ("Internet Relay Chat Protocol"), 6667/tcp falls inside the registered ircu range 6665-6669/tcp, and 6697/tcp is registered as ircs-u ("Internet Relay Chat via TLS/SSL") against RFC 7194. All three are IANA registrations; 6667/tcp is the de-facto client default in practice rather than an unregistered port — so 529/udp should not be assumed to carry IRC traffic in practice.

Exposure

No confirmed real-world deployment of 529/udp was found; treat any observed traffic as anomalous rather than assume a legitimate IRC-related service.

Malware/Trojan

No CVE or verified malware family is tied to 529/udp as of an August 2026 search; generic port-database "virus/trojan flag" boilerplate could not be independently confirmed.

IANA reference

The Reference column for irc-serv is blank — no RFC or protocol document is on file. [Confirmed] — the IANA Service Name and Transport Protocol Port Number Registry irc-serv 529

Prevalence

nmap-services open-frequency for 529/udp is 0.000544 (~0.05%); the 529/tcp entry samples at exactly 0. [Confirmed] — this site's own tooling (nmap-services)

IANA assignment

irc-serv — "IRC-SERV"; reference (blank — no RFC cited); assignee Brian_Tackett; dual-registered 529/tcp + 529/udp [Confirmed] — the IANA Service Name and Transport Protocol Port Number Registry irc-serv 529

Range class

well-known (0–1023) [Confirmed] — the IANA Service Name and Transport Protocol Port Number Registry irc-serv 529

Prevalence

nmap-services open-frequency 529/udp ≈ 0.000544 (~0.05%); 529/tcp ≈ 0 (sampled, not observed open) [Confirmed] — this site's own tooling (built from nmap-services)

Related ports

194/tcp (irc, registered); 6667/tcp (inside the registered ircu range 6665-6669/tcp, and the de-facto client default in practice); 6697/tcp (ircs-u, registered 2014-02-11 with Reference RFC 7194)

[Confirmed] — the IANA Service Name and Transport Protocol Port Number Registry irc 194/tcp, ircu 6665-6669/tcp, ircs-u 6697/tcp

Primary use

registered IRC-server-related use per the IANA service name; no RFC or independent protocol documentation describing an actual irc-serv wire protocol was found [Likely] — the IANA Service Name and Transport Protocol Port Number Registry irc-serv 529; https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=irc-serv

Other/unofficial uses

none verified; no vendor doc, blog post, or forum sighting of software using 529/udp was found [Unknown]

Security implications

no CVE or malware family verified as tied to 529/udp as of an August 2026 search; the port is essentially never observed open [Unknown]

Typically seen on

not commonly observed on any particular host type; an unexpected listener should be treated as anomalous [Unknown]

Analyst note

529/udp has no attested real-world deployment; if seen open, investigate rather than assume routine IRC infrastructure.