List of Blocked Ports

To maintain a secure and reliable service, the following ports are blocked to protect against abuse, unauthorized activities, and malicious attacks:

Email and Spam Prevention

Ports 25, 465, 587: SMTP
Ports 2525, 3535: Alternate SMTP ports
Port 7025: SMTP over TLS

Reason: These ports are used for sending email. Blocking them helps prevent unsolicited spam or misuse of our service for email abuse.

File Sharing and P2P (Peer-to-Peer)

Ports 6881-6889: BitTorrent
Port 6969: BitTorrent tracker

Reason: File-sharing services such as BitTorrent consume large amounts of bandwidth and are often linked to illegal activities. Blocking these ports ensures fair use of our service.

Remote Administration and Exploits

Ports 23, 2323: Telnet
Port 4444: Metasploit
Ports 5920-5921: PCAnywhere

Reason: These ports are commonly exploited for unauthorized remote access or hacking. Blocking them keep our services from being used to exploit other systems.

Database Ports (Prevent Data Exfiltration)

Port 3306: MySQL
Port 5432: PostgreSQL
Port 1521: Oracle Database
Port 27017: MongoDB
Ports 1433-1434: Microsoft SQL

Reason: Exposing database services over the internet can lead to data theft or unauthorized access. Blocking these ports ensures that sensitive information remains secure.

Network Services and Management

Ports 67-68: DHCP
Port 123: NTP
Port 1900: SSDP
Port 5353: mDNS
Ports 161-162: SNMP

Reason: These network services can be exploited for attacks such as DDoS or unauthorized device discovery. Blocking them helps prevent misuse of network infrastructure.

Voice-over-IP (VoIP) and Real-time Protocols

Ports 5060-5061: SIP
Ports 16384-32767: RTP

Reason: VoIP protocols can be used for toll fraud or unauthorized communication. Blocking these ports reduces the risk of abuse in voice services.

Legacy and Insecure Services

Port 135: RPC
Ports 137-139: NetBIOS
Port 445: SMB

Reason: These legacy services are known targets for malware and network attacks. Blocking them helps protect against unauthorized access and data breaches.

Messaging and Botnet Command-and-Control

Ports 6660-6669, 7000: IRC

Reason: These ports are often used by botnets to communicate and spread malware. Blocking them prevents infected devices from being controlled by malicious actors.

DNS (Potential Abuse and Amplification Attacks)

Port 53: DNS

Reason: DNS services can be abused for DDoS amplification attacks. We are providing DNS to you directly, so going through us to another DNS server makes no sense and raises suspicions. Would only be used in this fashion for amplification attacks.