Asus Merlin Iptables to Secure My Network

[oOMrYairOo]

Hello, I have ax88u running the latest merlin, I want to secure whit iptables to block all UDP port scanners out there simply to drop UDP SYN and etc bots, how can I achieve this?

 

[ColinTaylor]

SYN is a TCP flag. It does not exist for UDP.

Almost all port scanners are TCP.

The router's firewall drops all unsolicited connections by default.

Firewall > General >Enable DoS protection will block certain TCP flag combinations.

with not whit.

Definition of WHIT

the smallest part or particle imaginable : bit… See the full definition

www.merriam-webster.com

 

[AndreiV]

The ASUS firewall drops all unsolicted packets by default.

Merlin Add Ons are here > Add Ons .

 

[oOMrYairOo]

ok but let's say i open sip port 5060 UDP how i can hide it from UDP scanners, if I open 5060 USD and test it whit shodan then I get results from shodan that port 5060 UDP is open.

 

[ColinTaylor]

ok but let's say i open sip port 5060 UDP how i can hide it from UDP scanners

The only way to do that would be to specify an allowed source address in your port forwarding rule so that everything else is dropped.

with not whit.

Definition of WHIT

the smallest part or particle imaginable : bit… See the full definition

www.merriam-webster.com

 

[Tech9]

with not whit

With 5060 USD available it doesn't matter.

if I open 5060 USD

 

[ColinTaylor]

With 5060 USD available it doesn't matter.

Yeah, I thought $5,060 was rather expensive.

 

[Tech Junky]

Close everything and allow only originated traffic. If you originate an outbound session to UDP:5060 then on the return path your system should allow the traffic back into your network.

 

[oOMrYairOo]

Ok, thanks, guys.