Port 27901Quake II Master Server

Ports 27901 through 27910 are utilized by id Software's Quake II master server for coordinating multiplayer game sessions. These ports enable clients to discover active game servers and facilitate connections, primarily over UDP, to support the rapid exchange of game state information necessary for seamless multiplayer gameplay..

transport
udp

single transport

in transit
cleartext

payload readable on path

assignment
unofficial

used by convention

risk
4/10

caution

lookups
8,474

rank 593 of 993 · top 60%

Technical Details

what runs on :27901

The Quake II master server operates over a range of UDP ports, typically from 27901 through 27910. This collection of ports allows game clients to query the master server for a list of available game servers hosting Quake II matches. Clients send request packets, and the master server responds with server addresses, enabling players to quickly find active games.

Communication primarily leverages the UDP protocol to minimize latency, which is crucial for real-time multiplayer interactions. The UDP-based design reduces overhead and accommodates the low-latency needs of first-person shooter games. Although TCP is not typically used on these ports, UDP packets enable fast-paced data exchange crucial for gameplay discovery.

This server infrastructure supports the foundational matchmaking layer within the Quake II ecosystem. It serves as a directory and not as a relay for the actual gameplay data, which happens on different server ports dedicated to hosting the matches themselves.

Security Information

exposure of :27901

risk score

4/ 10caution

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

gaming averages 4.0 across 124 ports — this one sits level with it.

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 these ports are open to the public internet, they can be susceptible to DDoS attacks intended to overwhelm the master server service.
  • Attackers might exploit improperly secured master servers by flooding them with fake requests, causing service degradation or enumeration attacks.
  • If any outdated server software is running, it may be vulnerable to known exploits.

Common Mitigations:

  • Implement rate limiting and DDoS protection measures to prevent overload and malicious flooding.
  • Use authentication or verification mechanisms to limit requests from untrusted sources.
  • Regularly update server software to patch known vulnerabilities.
  • Employ network monitoring and anomaly detection to quickly identify and block suspicious activity targeting these ports.

the 8 most looked-up other ports in gaming — 124 ports carry that label.

risk mix of the 8 listed

  • caution100%

0 of 8 encrypted