Port 514RSH / REMSH

Remote Shell (rsh or remsh) is a legacy protocol designed to execute shell commands on a remote Unix system in a non-interactive fashion. It operates primarily over TCP, allowing administrators or automated systems to issue single commands remotely. Despite its historical usage, RSH is largely deprecated due to its insecure design, transmitting data in plaintext, including user credentials, posing significant security risks in modern network environments..

transport
tcp

single transport

in transit
cleartext

payload readable on path

assignment
official

registered with iana

risk
4/10

caution

lookups
9,159

rank 530 of 993 · top 53%

1 other service is registered on port 514. compare all 2

Technical Details

what runs on :514

Remote Shell (RSH) is part of the Berkeley r-commands suite, enabling users to execute single, non-interactive commands remotely. Unlike interactive sessions offered by protocols like Telnet or SSH, RSH executes the specified command and then disconnects. It is primarily used for scripting, remote system administration, and automation, particularly in trusted local network environments.

RSH communicates over TCP port 514. Authentication is traditionally based on trust relationships defined in .rhosts or /etc/hosts.equiv files, which determine user mapping and access permissions without requiring passwords, relying heavily on trust between systems. As such, it was commonly used within secured, internal networks with known hosts.

Due to the lack of encryption and strong authentication mechanisms, RSH protocols have fallen out of favor. Today's best practices replace RSH with Secure Shell (SSH), which provides robust encryption and authentication, addressing the security deficiencies inherent in RSH.

Security Information

exposure of :514

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 3.8 across 216 ports — this one sits 0.2 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:

  • Transmits credentials and data in plaintext, susceptible to eavesdropping and interception by attackers.
  • Trust-based authentication easily exploited if rhosts or hosts.equiv files are misconfigured or compromised.
  • Susceptible to IP address spoofing, allowing unauthorized access by impersonating trusted hosts.
  • No support for modern access controls or strong identity verification.

Common Mitigations:

  • Completely disable RSH services on all hosts; replace with SSH where possible.
  • Remove or tightly restrict any rhosts or hosts.equiv trust files if RSH must remain enabled.
  • Implement strict network segmentation/isolation to minimize exposed RSH attack surfaces.
  • Monitor network traffic for unauthorized use of port 514 and unusual remote command activity.
  • Apply host firewalls to block inbound TCP port 514 requests except from explicitly trusted sources (preferably none).

the 8 most looked-up other ports in security — 216 ports carry that label.

risk mix of the 8 listed

  • caution100%

3 of 8 encrypted