Port 1352Lotus Notes RPC

Port 1352 is primarily used for IBM Lotus Notes and Domino servers to communicate using a proprietary Remote Procedure Call (RPC) protocol. This protocol facilitates messaging, database, and directory services within the IBM collaboration suite, ensuring clients and servers exchange commands and data efficiently across networks..

transport
tcp

single transport

in transit
cleartext

payload readable on path

assignment
official

registered with iana

risk
4/10

caution

lookups
12,263

rank 319 of 993 · top 32%

Technical Details

what runs on :1352

Overview
IBM Lotus Notes and Domino rely on port 1352 to establish remote procedure call (RPC) sessions between clients, application servers, and database services. This protocol enables real-time collaboration features, including email, calendar management, and directory lookups by transmitting commands and data objects across distributed systems.

RPC Functionality
The Domino RPC protocol is proprietary, facilitating tightly integrated communication that allows Lotus Notes clients to access mail databases, replicate data, query directories, and perform administrative actions. It supports session management features such as authentication exchanges, transaction controls, and command queuing, all over a session-oriented transport like TCP.

Protocol Details
Typically utilizing TCP, the protocol handles various Notes client operations including opening mailboxes, directory lookups, or database replication. Given its proprietary nature, detailed protocol specifications are limited publicly. The communications are generally not encrypted unless additional security layers are implemented through Domino configuration or network-level protections such as VPNs.

Security Information

exposure of :1352

risk score

4/ 10caution

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

email averages 3.9 across 42 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

every listening transport is another surface to filter at the edge

security overview

Common Vulnerabilities:

  • Unauthorized access: Without strong authentication, attackers may connect to Lotus Domino services and access sensitive data.
  • Data interception: As traffic is often unencrypted, it is susceptible to eavesdropping and man-in-the-middle attacks.
  • Denial-of-Service (DoS): Services on port 1352 can be targeted by DoS attacks to overload or crash Domino services.
  • Exploit of legacy features: Older Domino versions may expose vulnerabilities related to buffer overflows or flawed access controls.

Mitigation Strategies:

  • Enable strong authentication and access controls to limit who can use RPC services.
  • Enforce encryption on RPC traffic via built-in Domino SSL capabilities or through VPN tunnels.
  • Apply security patches and updates to address known vulnerabilities.
  • Use firewalls to restrict external access, exposing port 1352 only to trusted internal networks or VPN clients.
  • Monitor for anomalies in traffic and authentication attempts to detect possible intrusions or attacks.

Related Ports

all 42 in email

the 8 most looked-up other ports in email — 42 ports carry that label.

portservicerisk
:143IMAPcaution
:995POP3Scaution
:109POP2caution
:2096cPanel SSL Webmailsafe
:110POP3caution
:993IMAPScaution
:24Private Mailcaution
:7025Zimbra LMTPcaution

risk mix of the 8 listed

  • safe13%
  • caution88%

3 of 8 encrypted