Port 525Timed Timeserver

The Timed Timeserver is a legacy service used primarily on Unix-based systems to synchronize time across networked devices. Operating over UDP port 525, it helps keep system clocks consistent on connected machines within a local network, which is essential for accurate log timestamps, scheduled tasks, and overall network coordination..

transport
udp

single transport

in transit
cleartext

payload readable on path

assignment
official

registered with iana

risk
2/10

safe

lookups
6,786

rank 754 of 993 · top 76%

Technical Details

what runs on :525

The Timed Timeserver protocol is a simple network service designed to maintain clock synchronization across multiple hosts on a local area network. Running over UDP port 525, this daemon exchanges time information between systems through a series of broadcast or unicast messages to detect discrepancies in system times.

Timed is mainly found on older Unix systems, leveraging a relatively straightforward algorithm for choosing the most accurate clock among connected hosts, then adjusting participant clocks to align within an acceptable margin of error. Unlike more modern approaches, Timed lacks sophisticated error correction or resilience features.

Today, Timed has largely been superseded by the Network Time Protocol (NTP), which offers greater accuracy, security, and scalability. Nonetheless, Timed may still be encountered in legacy Unix environments that have not transitioned to more modern time synchronization protocols.

Security Information

exposure of :525

risk score

2/ 10safe

routine exposure. this port is rarely the way in on its own — keep it patched and logged and move on.

network services averages 3.9 across 604 ports — this one sits 1.9 below.

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

udp

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

security overview

Common vulnerabilities:

  • Susceptibility to spoofing due to lack of encryption or authentication, which allows attackers to send false time updates, impacting system operations.
  • Exposure to denial-of-service (DoS) attacks by flooding the service with traffic or malformed packets, potentially disrupting synchronization.
  • Use of UDP allows for easier IP spoofing, increasing the attack surface.

Common mitigations:

  • Disable Timed in favor of secure alternatives like NTP with authentication.
  • Restrict access to port 525 UDP using firewalls or Access Control Lists (ACLs), permitting only trusted hosts.
  • Employ network segmentation to isolate critical systems from untrusted networks.
  • Monitor network traffic for unusual activity targeting port 525.

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