Port 218Message Posting Protocol

The Message Posting Protocol (MPP) operates on port 218 and facilitates the transfer and management of message posts across networked systems. It provides a mechanism for clients and servers to communicate by supporting both TCP and UDP transport. Widely referenced in official port documentation, it serves specific messaging-centric applications in distributed environments..

transport
tcp · udp

2 transports registered

in transit
cleartext

payload readable on path

assignment
official

registered with iana

risk
4/10

caution

lookups
7,379

rank 693 of 993 · top 70%

Technical Details

what runs on :218

Message Posting Protocol (MPP) is designed to enable systems to post, transfer, and update messages across network nodes. MPP supports both connection-oriented (TCP) and connectionless (UDP) transports, providing flexibility depending on the requirements of reliability or speed.

MPP facilitates various functions such as message creation, retrieval, deletion, and management. It may operate similarly to basic networked messaging services by structuring message envelopes, addressing, and sequencing to ensure orderly communication between multiple clients and servers.

Although not widely utilized in mainstream modern messaging, MPP's standardized port assignment persists for compatibility with legacy systems and specialized applications. Its simplicity allows integration within lightweight or custom communication frameworks where structured message exchange is necessary.

Security Information

exposure of :218

risk score

4/ 10caution

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

network services averages 3.9 across 604 ports — this one sits 0.1 above.

in transit

cleartext

credentials and payloads are readable by anyone on path

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

Common vulnerabilities associated with MPP arise from its lack of encryption by default, potentially allowing interception and unauthorized reading or modification of messages in transit. If input validation is insufficient, it may be susceptible to injection attacks or buffer overflows, depending on server implementation.

Mitigations should include deploying MPP behind secure network boundaries, such as firewalls or VPNs. When possible, tunnel communications within encrypted channels (TLS/SSL) to protect data confidentiality. Regularly updating software and applying input validation and authentication controls significantly reduce risks from exploitation.

the 8 most looked-up other ports in network services — 604 ports carry that label.

risk mix of the 8 listed

  • caution100%

0 of 8 encrypted