what port does File and Printing sharing use?

blackzone

As topic. Can't find a quick answer for it with google

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sprkymrk

It's basically all the netbios stuff. Ports like 135, 137, 138, 139, 445, etc.

From a quick Google search with search string "site:microsoft.com ports protocols "file and print sharing""

The following ports are associated with file sharing and server message block (SMB) communications:
• Microsoft file sharing SMB: User Datagram Protocol (UDP) ports from 135 through 139 and Transmission Control Protocol (TCP) ports from 135 through 139.
• Direct-hosted SMB traffic without a network basic input/output system (NetBIOS): port 445 (TCP and UPD).

bighornsheep

Does it not work for you in your network? Or are you trying to open up file and sharing port on your firewall?

It's NetBIOS, which isnt routable on the Internet. If you wanna share your files, you will need to setup HTTP server, or FTP server.

If you're having problems using file sharing on your network, perhaps it's a different issue. ie. Permissions, protocols configurations, account policies.

Cheers.

sprkymrk

bighornsheep wrote:

It's NetBIOS, which isnt routable on the Internet. If you wanna share your files, you will need to setup HTTP server, or FTP server.

You still need to filter those ports on your Internet side and/or disable it on the Internet side adapter. NetBIOS also defines a protocol that operates at the OSI Session layer, which is implemented by the underlying protocol implementation, such as NetBIOS over TCP/IP (NetBT), defined by RFCs 1001 and 1002.

We're all aware of the old trick to try anonymous enumeration of Windows systems:
net use \\x.x.x.x\ipc$ "" /u:""

There are also a plethora of tools that can cause trouble if you don't block this at your firewall such as epdump, rpcdump, nbtscan, etc.