dan87 Posted July 21, 2003 Share Posted July 21, 2003 Hi. I was wondering if anyone had a good list of ports to block on linksys routers? Obviously 135-139 for netbios, but what else? Does linksys leave very many ports open by default? Finally, does anyone have any security hardening guides for the linksys? I know of a few good ones, like disable dhcp, ssid, setup private mac filters, and using wep, but what else? Thank you Link to comment Share on other sites More sharing options...
Jon Posted July 21, 2003 Share Posted July 21, 2003 If you want to be secure, block all ports and open the ones you need.... Link to comment Share on other sites More sharing options...
+BudMan MVC Posted July 21, 2003 MVC Share Posted July 21, 2003 You are talking outbound - are you not? Since by default, no inbound ports are open. Link to comment Share on other sites More sharing options...
dan87 Posted July 21, 2003 Author Share Posted July 21, 2003 No, I'm talking about inbound.... is that really true, no inbound ports are open (besides 80 for browsing)? Why then do people warn that you should block netbios ports on the linksys router? Link to comment Share on other sites More sharing options...
Steven Posted July 21, 2003 Share Posted July 21, 2003 No, I'm talking about inbound.... is that really true, no inbound ports are open (besides 80 for browsing)? Why then do people warn that you should block netbios ports on the linksys router? you can always disable netbios in your Network Configuration in windows. Disable NetBIOS over TCP/IP. Link to comment Share on other sites More sharing options...
dan87 Posted July 21, 2003 Author Share Posted July 21, 2003 well i'm running some AD tests, so I have to keep it on. Normally though, yeah, I turn it off anyways and just use smb Link to comment Share on other sites More sharing options...
Eversurf Posted July 21, 2003 Share Posted July 21, 2003 All ports are blocked by default. Each time you send a packet out it get's tag with the NAT port number and when that packet comes back it knows which port to use to make throught the router. The only worrie you should have about this type of firewall is that application from the inside can access the wan. If a rogue application sends packet out, the router will let them go outside and come back in, but a good anti virus will pick those program up Have fun Link to comment Share on other sites More sharing options...
dan87 Posted July 21, 2003 Author Share Posted July 21, 2003 right. i use sygate to block any trojan crap or spyware that tries to make an outbound connection. I'm just suprised to find out the linksys router blocks all ports by default - this is what I'd expect from a firewall, I was just under the impression that it wasn't blocking all of them, since I read in some newsgroup that people were manually blocking 135-139, but I guess that isn't needed afterall. Thanks for the help Link to comment Share on other sites More sharing options...
+BudMan MVC Posted July 21, 2003 MVC Share Posted July 21, 2003 All inbound are blocked, as I stated and eversurf expanded on. But what you can do is block 137-139 and 445 from going outbound. This is really not required, but this would ensure that nothing is going outbound on these ports, that may let someone know stuff about you, etc.. Also, if you ever put a machine into the linksys dmz - this type of rule will help ensure that there is no netbios stuff going on to the outside world. Link to comment Share on other sites More sharing options...
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