Port 4690Prelude Communication Protocol (PCP)

Prelude sensors use this port to send intrusion-detection alerts to a Prelude Manager.

transport: tcp · udp
in transit: encrypted
assignment: official
risk: 4/10
lookups: 0

also known as Prelude IDS message protocol, PCP

Technical Details

what runs on :4690

Prelude Manager commonly listens on TCP port 4690 for connections from Prelude sensors and other components. The protocol transports IDMEF security events, typically over TLS, with clients configured using Prelude credentials; TCP is the usual deployment, although IANA lists both TCP and UDP for the service. This is an IDS/SIEM event-ingestion endpoint, not a general-purpose remote shell.

Security Information

exposure of :4690

risk score

4/ 10caution

worth attention. how exposed you are depends on configuration — don't leave it reachable from the internet without a reason.

security averages 3.0 across 378 ports — this one sits 1.0 above.

in transit

encrypted

payloads are protected on the wire

assignment

official

registered with iana for this service — scanners fingerprint it by number

reachable over

tcp · udp

udp is connectionless — source addresses are trivially spoofed and it is a reflection favourite

security overview

Keep the manager reachable only from trusted sensor networks rather than exposing it to the internet. TLS and configured client credentials help protect the connection, but compromised sensor credentials or an exposed manager could allow forged alert submissions, and any network-facing parser can be a target for denial of service or implementation flaws.

Record

iana registry entry

port: :4690
service: Prelude Communication Protocol (PCP)
transport: TCPUDP
encryption: tls / encrypted
assignment: iana registered
risk: 4/10caution
category: Security Network Services
usage: Prelude sensors and related components use the Prelude Communication Protocol to send alerts to a Prelude Manager. Engineers are most likely to encounter it on TCP/4690 inside a network running the Prelude IDS/SIEM; the registry also lists UDP.
lookups: 0rank 993
added: 2026-10-05
updated: 2026-10-05
references: IANA service name registry — port 4690

Something wrong?

This record is maintained by the engineers who use port 4690. Every field on it is editable — change what's wrong, say how you know, and a reviewer publishes it, usually within a minute. Last touched 2026-10-05.

01edit any field on a page of its own
02a model checks it for accuracy and spam
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edit this record →back to the registry

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risk mix of the 8 listed

caution100%

2 of 8 encrypted

Port :4690Prelude Communication Protocol (PCP)

Technical Details

Security Information

Related Ports

Port 4690Prelude Communication Protocol (PCP)