Port 5499Hotline Tracker Discovery

**Hotline Tracker Discovery** is a service used primarily for finding available Hotline servers, popular in late 1990s and early 2000s for community chat, file sharing, and messaging. The protocol allows Hotline clients to locate tracker servers that maintain listings of available Hotline community servers..

transport
udp

single transport

in transit
cleartext

payload readable on path

assignment
unofficial

used by convention

risk
4/10

caution

lookups
6,370

rank 793 of 993 · top 80%

Technical Details

what runs on :5499

Hotline Tracker Discovery on UDP port 5499 was an essential part of the Hotline Connect ecosystem. Clients broadcast queries on this port to locate tracker servers, which maintained lists of alive Hotline community servers for users to join. Communication was lightweight and connectionless, favoring UDP for speed and efficiency in the discovery process.

The protocol operates by sending simple query packets which tracker servers answer with available server information, IP addresses, and service details. This decentralizes the process of finding servers, increasing flexibility but also relying heavily on trackers staying updated and maintained.

Although largely obsolete today, the protocol historically enabled dynamic discovery and connection management for a distributed social networking and file exchange environment, predating many modern peer-to-peer service discovery approaches.

Security Information

exposure of :5499

risk score

4/ 10caution

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

file transfer averages 4.1 across 114 ports — this one sits 0.1 below.

in transit

cleartext

credentials and payloads are readable by anyone on path

assignment

unofficial

used by convention, not registered — what answers here varies by deployment

reachable over

udp

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

security overview

Common vulnerabilities:

  • Since it uses UDP without encryption or authentication, discovery packets can be spoofed, captured, or manipulated.
  • Attackers could poison tracker lists with malicious or fake servers.
  • The open, unauthenticated nature made it susceptible to denial-of-service by flooding trackers.

Common mitigations:

  • Restrict inbound and outbound UDP port 5499 traffic at the network perimeter.
  • Deprecate or disable legacy Hotline Tracker services entirely.
  • Use monitoring to detect unusual discovery broadcast volumes or spoofing attempts.
  • Implement authentication and encryption layers if still needing to run compatible services.

the 8 most looked-up other ports in file transfer — 114 ports carry that label.

risk mix of the 8 listed

  • caution100%

1 of 8 encrypted