The port most susceptible is TCP Port is 139, the NetBIOS Session Service port. Although port 139 is the most commonly attacked port, there is potential for successful attacks on other ports as well. This attack can be executed for both local and external systems.
- 1 What does TCP port 139 do?
- 2 What is UDP 139 used for?
- 3 Why is port 139 open?
- 4 What are vulnerable ports?
- 5 What are ports 137 and 138 used for?
- 6 How do I close port 139?
- 7 What is the protocol for port 138?
- 8 What is NetBIOS 139?
- 9 What is the difference between port 139 and 445?
- 10 What uses TCP port 135?
- 11 Which ports should be blocked?
- 12 What is vulnerability sweep?
- 13 How can a firewall be used to stop attacks using ports?
What does TCP port 139 do?
Port 139 is used for File and Printer Sharing but happens to be the single most dangerous Port on the Internet. Once an attacker has located an active Port 139 on a device, he can run NBSTAT a diagnostic tool for NetBIOS over TCP/IP, primarily designed to help troubleshoot NetBIOS name resolution problems.
What is UDP 139 used for?
Side note: UDP port 139 uses the Datagram Protocol, a communications protocol for the Internet network layer, transport layer, and session layer. This protocol when used over PORT 139 makes possible the transmission of a datagram message from one computer to an application running in another computer.
Why is port 139 open?
The port is currently ‘listening. If you are on Windows-based network that is running NetBios, it is perfectly normal to have port 139 open in order to facilitate that protocol. If you are not on a network using NetBios, there is no reason to have that port open.
What are vulnerable ports?
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)
What are ports 137 and 138 used for?
Ports 137, 138, and 139 are used by NetBIOS, which does not support IPv6. CIFS is required for Windows file service. You can disable CIFS by issuing the cifs terminate command on your storage system console.
How do I close port 139?
To close port 139 (netbios-nbsession):
- Click on “Start” → “Settings” → “Control Panel”
- Double click on “Network”
- Select the “Configuration” tab.
- Scroll down network component list and find and select item starting with “TCP/IP -> “
- Then select “Properties”
- Select the “Bindings” tab.
- Deselect each option then click “Ok”
What is the protocol for port 138?
Side note: UDP port 138 uses the Datagram Protocol, a communications protocol for the Internet network layer, transport layer, and session layer. This protocol when used over PORT 138 makes possible the transmission of a datagram message from one computer to an application running in another computer.
What is NetBIOS 139?
Port 139: SMB originally ran on top of NetBIOS using port 139. NetBIOS is an older transport layer that allows Windows computers to talk to each other on the same network. Port 445: Later versions of SMB (after Windows 2000) began to use port 445 on top of a TCP stack. Using TCP allows SMB to work over the internet.
What is the difference between port 139 and 445?
Port 139 is used by SMB dialects that communicate over NetBIOS. It’s a transport layer protocol designed to use in Windows operating systems over a network. Port 445 is used by newer versions of SMB (after Windows 2000) on top of a TCP stack, allowing SMB to communicate over the Internet.
What uses TCP port 135?
Microsoft Windows Networking Services Port 135 is used for RPC client-server communication; ports 139 and 445 are used for authentication and file sharing.
Which ports should be blocked?
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.
What is vulnerability sweep?
Game Description: Vulnerability Sweep analyzes enemy shield frequencies and hull vulnerabilities within an area around a specified target. These vulnerabilities are highlighted, and the information is processed and disseminated to allies to aid their ships’ targeting parameters.
How can a firewall be used to stop attacks using ports?
Firewalls provide protection against outside cyber attackers by shielding your computer or network from malicious or unnecessary network traffic. Firewalls can also prevent malicious software from accessing a computer or network via the internet.