Firewall/NAT

Is it possible to gain access to the internal LAN via a broadband (ADSL) router, if I know the router password?
I've heard that users should always change their default router passwords as this can be exploited to allow hackers to gain access to the internal LAN (computers connected to the router) and can gain access to files stored on every pc on that lan. Is this true? If yes, then how is it done? I have done some searching but came up with nothing. Please enlighten us on this matter.
I have also read some threads which says that certain ports should be forwarded to be able to gain access to the internal Lan, but this was not very clear.
What is a malicious user able to accomplish if he knows the password of my broadband (ADSL) router? (Besides knowing my WAN username & password and resetting my router)
Any comments will be much appreciated

Even if someone couldn't get into your LAN, it could still be possible for them to manipulate your router in such a way as to convert it into a proxy they could use to (ab)use your internet connection. That (ab)use would appear to be coming from your IP address and you could be held accountable for it.

Can't you just disable WAN login? If thats now how it works by default, as on some cheap "home-routers".
I'm in no need for WAN-login, so I'd rather want it disabled, to give one less user/pass for someone to try and hack.

i understand, but the point i want to know more about is whether it is possible at all to access the internal lan

Come to think of it, probably WAN-login is NOT enabled?
Since most people probably have a http-server at home, and having a forwarding rule for it, so any attempt to connect to port 80 on the router will end up at the internal webserver.

I think its something you might need to enable, and if its not enabled noone has a chanse of logging in to your router from the outside...right?

its possible to login to any router from the internet. Actually, anybody on the internet is able to access your router, if you have left your default password the attacker is able to login to your router very easily.
But the big question is: IS IT POSSIBLE FOR THE ATTACKER TO ACCES  YOUR INTERNAL LAN?

its possible to login to any router from the internet. Actually, anybody on the internet is able to access your router, if you have left your default password the attacker is able to login to your router very easily.
But the big question is: IS IT POSSIBLE FOR THE ATTACKER TO ACCES  YOUR INTERNAL LAN?

Not my current home-router, a cheap Netgear. Only LAN-login on that one, unless you turn WAN-login (remote management they call it) on.

Anyway, if anyone manages to log in to your router, of course they can do whatever they like in it, like disable all firewall rules and put your LAN into some DMZ just opening all ports up.
But then they'll still need to hack your pc's, so if you have fully updated windows machines with personal  firewalls and antivirus and stuff, I dont know how easy it'll be exploiting them....

once logged in to the router, does anyone know how to see all the ip addresses of the pcs connected to that router?

I think it's time for you to take this question elsewhere. It never was related to m0n0wall and seems more appropriate to hacking forums.

Yes, it is possible. I'm leaving it at that because there is nothing good you could do if I told you how. I'm also going to lock your duplicate threads because they aren't m0n0wall related, this isn't a training grounds for script kiddies, which is where this appears to be going.

If you have m0n0wall-specific questions, you're welcome to start new threads. You are NOT welcome to start more threads along these lines.