Commonly Abused Ports
- Port 20,21 FTP. An outdated and insecure protocol, which utilize no encryption for both data transfer and authentication.
- Port 22 SSH.
- Port 23 Telnet.
- Port 25 SMTP.
- Port 53 DNS.
- Port 139 NetBIOS.
- Ports 80,443 Used by HTTP and HTTPS.
- Port 445 SMB.
https://www.youtube.com/watch?v=UE1Pv3xYN_A
What ports should always be closed?
For example, the SANS Institute recommends blocking outbound traffic that uses the following ports:
- MS RPC TCP & UDP port 135.
- NetBIOS/IP TCP & UDP ports 137-139.
- SMB/IP TCP port 445.
- Trivial File Transfer Protocol (TFTP) UDP port 69.
- Syslog UDP port 514.
Which ports are most vulnerable?
The Critical Watch Report of 2019 claims that 65% of vulnerabilities found in Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) ports are linked to SSH (22/TCP), HTTPS (443/TCP), and HTTP (80/TCP). This is followed by RDP/TCP which has been patched numerous times by Microsoft.
Which ports are secure?
Port 22 is SSH (Secure Shell), port 80 is the standard port for HTTP (Hypertext Transfer Protocol) web traffic, and port 443 is HTTPS (Hypertext Transfer Protocol Secure)the more secure web traffic protocol.
What ports should always be open?
Which Ports Are Usually Open By Default?
- 20 FTP (File Transfer Protocol)
- 22 Secure Shell (SSH)
- 25 Simple Mail Transfer Protocol (SMTP)
- 53 Domain Name System (DNS)
- 80 Hypertext Transfer Protocol (HTTP)
- 110 Post Office Protocol (POP3)
- 143 Internet Message Access Protocol (IMAP)
- 443 HTTP Secure (HTTPS)
What is port 135 commonly used for?
Port 135 is used for RPC client-server communication; ports 139 and 445 are used for authentication and file sharing. UDP ports 137 and 138 are used for local NetBIOS browser, naming, and lookup functions.
Should port 21 be closed?
Inbound ports are an open door into an operating system.This port should be blocked. Port 21 Used by FTP to allow file transfers. Most hosts on your network are not intended to be FTP Servers – don’t leave doors open that don’t need to be open.
What ports do hackers use?
Commonly Hacked Ports
- TCP port 21 FTP (File Transfer Protocol)
- TCP port 22 SSH (Secure Shell)
- TCP port 23 Telnet.
- TCP port 25 SMTP (Simple Mail Transfer Protocol)
- TCP and UDP port 53 DNS (Domain Name System)
- TCP port 443 HTTP (Hypertext Transport Protocol) and HTTPS (HTTP over SSL)
Is port 80 safe to open?
Forwarding port 80 is no more insecure than any other port. In fact, port forwarding itself is not inherently insecure. The security concern is that it allows services that are normally protected behind some kind of firewall to be accessible publicly.
Is port 443 safe to open?
Port 443 is a virtual port that computers use to divert network traffic.HTTPS is secure and is on port 443, while HTTP is unsecured and available on port 80. Information that travels on the port 443 is encrypted using Secure Sockets Layer (SSL) or its new version, Transport Layer Security (TLS) and hence safer.
What are bad ports?
“Bad” TCP/UDP Ports List
| 31/tcp | Agent 31, Hackers Paradise, Masters Paradise |
|---|---|
| 33567/tcp | Backdoor rootshell via inetd (from Lion worm) |
| 33568/tcp | Trojaned version of SSH (from Lion worm) |
| 40421/tcp | Masters Paradise Trojan horse |
| 60008/tcp | Backdoor rootshel via inetd (from Lion worm) |
Can open ports be hacked?
Open port does not immediately mean a security issue. But, it can provide a pathway for attackers to the application listening on that port. Therefore, attackers can exploit shortcomings like weak credentials, no two-factor authentication, or even vulnerabilities in the application itself.
Why are open ports bad?
Open ports can be dangerous when the service listening on the port is misconfigured, unpatched, vulnerable to exploits, or has poor network security rules.The reason people call for closed ports because less open ports reduces your attack surface.
Is port 80 blocked?
Blocked Ports
Most residential ISP’s block ports to combat viruses and spam. The most commonly blocked ports are port 80 and port 25. Port 80 is the default port for http traffic. With blocked port 80 you will need to run your web server on a non-standard port.
Why is port 80 always open?
Note: TCP Port 80 is open for outgoing communications by default in most firewall software. So you should not have to open any ports in the firewall software running on Rhino workstations.
What is the port 8080 used for?
web servers
Port number 8080 is usually used for web servers. When a port number is added to the end of the domain name, it drives traffic to the web server.
What is TCP 161?
Port 161 is the default port on network devices to which SNMP queries are sent during the discovery and monitoring processes.
What is the port 3389?
Remote Desktop Protocol
Remote Desktop Protocol (RDP) is a Microsoft proprietary protocol that enables remote connections to other computers, typically over TCP port 3389. It provides network access for a remote user over an encrypted channel.
What uses TCP port 445?
TCP port 445 is used for direct TCP/IP MS Networking access without the need for a NetBIOS layer. This service is only implemented in the more recent verions of Windows (e.g. Windows 2K / XP). The SMB (Server Message Block) protocol is used among other things for file sharing in Windows NT/2K/XP.
Is Port 8080 Vulnerable?
2 on port 8080/TCP and 8081/TCP could allow a remote attacker to perform a Cross-Site Request Forgery (CSRF) attack, potentially allowing an attacker to execute administrative operations, provided the targeted user has an active session and is induced to trigger a malicious request.
What port is Telnet?
23
The default port for Telnet client connections is 23; to change this default, enter a port number between 1024 and 32,767.
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