Wardialing is one of the oldest methods of gaining unauthorized access to the targeted systems, it is one of the dangers most commonly forgotten by network engineers and system administrators. A hacker can sneak past all the expensive firewalls and IDS and connect easily into the network. Through wardialing, an attacker searches for the devices located in the target network infrastructure that are also accessible through the telephone line.
‘Dial backup’ in routers is most frequently found in networks where redundancy is required. Dial-on-demand routing (DDR) is commonly used to establish connectivity as a backup.
As a security tester, how would you discover what telephone numbers to dial-in to the router?