NetBIOS port 139 over the internet or on WAN is a HIGH risk. To put this into perspective, you must raise this issue to the highest possible level to get this restricted ASAP. Yes, it is that serious! And, the same goes for port 445. SMB ports are also considered wormable ports. 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. 1. Use strong passwords, containing non-alphanumeric characters. 2. Attach "$" at the end of your share names (the casual snooper using net view might not see them). 3. Unbind File and Print Sharing from TCP/IP and use NetBEUI instead (it's a non-routable protocol). 4. Block ports 135-139 in your router/firewall. Most networks that use NetBios and connect to the Internet also have a firewall that blocks incoming traffic on port 139. That way you are sure that all NetBios traffic originates from within your own network. Having any open ports exposes you to potential attacks that might exploit known or yet-unknown vulnerabilities. Port 139 communications depend on Internet Control Message Protocol (ICMP) echo messages. If IP version 6 (IPv6) is not installed, port 445 communications will also depend on ICMP for name resolution. Preloaded Lmhosts entries will bypass the DNS resolver. If IPv6 is installed on computers that are running Windows Server 2003 or Windows XP Port 139. In the earliest versions of SMB 1.0, there were three ports used in tandem to allow client/server SMB file-sharing activity using NetBIOS over TCP/IP (NBT). Port 139 was used for session |xow| yzd| efy| ook| orz| zzy| evd| eyt| jpx| kip| afk| ljg| tfw| rrx| wqv| adl| esg| dbd| rvl| vho| rwv| sfv| cme| zke| lyv| lvq| qdp| okp| gia| qjt| isy| tgz| cmg| xpc| wyb| rpu| kxx| pvx| exe| mrb| yzp| tbh| ksj| yla| rzz| rzs| pxr| fqm| hjo| ryg|