Yes the Chuck Norris trojan stays inside the router RAM. So when you turn it off, the contents of RAM are destroyed and the trojan gets killed. However if it has made changes to the DNS servers (in some DSL routers) then you will have to revert changes manually.
The best defense against such trojan is to turn on NAT / Firewall in your DSL router. That way an outsider cannot have access to your DSL interface. See your router documentation for details.
To check if your DSL router ca be accessed from outside (and so is vulnerable to Chuck Norris attack) :
- Find out your IP address from http://www.whatismyip.com/
- Then goto http://www.dnstools.com/
. Put in your IP address and select Check port 80
and Click Go.
If you see server is down
or Connection failed: Connection timed out
be happy as your DSL router has no outside access.
If you see something like Connected successfully to port 80
then you are open to rest of world. Do not tell me your IP address.