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SMTP & POP ports open (?)

I did a port scan on my router and it reported that the router is listening on ports 25 & 110. I don't have any mail services running behind the firewall. Why would the router be listening on these ports and how do I shut them off?

I am using ACLs & CBAC supposedly allowing only port 80,20,21 to my web server, and no public services (no telnet,ssh,snmp,http,etc) running on the router.


Re: SMTP & POP ports open (?)

Hi -

Was the router ever used for smtp/pop3 access? If you don't need the smtp/pop3 ACL's on the router then just open up a text-editor (notepad) and log onto the router (in config mode), copy the ACL's including the access-group cmd and paste on notepad, place a 'no access-list as the first line of your copied ACL's. Now amend the access-list accordingly i.e. delete the smtp/pop3 lines, now paste back onto the router your amemded ACL's (in config mode). Make sure to save the config with cmd: wr m (write memory) and your done!

Hope this helps -

New Member

Re: SMTP & POP ports open (?)

The router was never used for smtp/pop3 access.

My ACLs permit some ICMP and connections on ports 80,20,21. Everything else is denied from the outside. From the inside, it appears to be listening on smtp/pop3.

I checked a couple other routers and they are also listening for smtp/pop3. As far as I know, IOS doesn't have a smtp or pop3 service.

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