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Part III: Hacking Network Hosts
Physical security problems
Various physical security vulnerabilities can result in physical theft, the
reconfiguration of wireless devices, and the capturing of confidential information.
You should look for the following security vulnerabilities when testing
your systems:
✓ APs mounted on the outside of a building and accessible to the public.
✓ Poorly mounted antennas — or the wrong types of antennas — that
broadcast too strong a signal and that are accessible to the public. You
can view the signal strength in NetStumbler, your wireless client manager,
or one of the commercial tools I mention earlier in this chapter.
These issues are often overlooked because of rushed installations, improper
planning, and lack of technical knowledge, but they can come back to haunt
you. The book Wireless Networks For Dummies provides more details.
Countermeasures against physical
security problems
Ensure that APs, antennas, and other wireless and network infrastructure
equipment are locked away in secure closets, ceilings, or other places that
are difficult for a would-be intruder to access physically. Terminate your APs
outside any firewall or other network perimeter security devices — or at
least in a DMZ — whenever possible. If you place unsecured wireless equipment
inside your secure network, it can negate any benefits you would get
from your perimeter security devices, such as your firewall.
If wireless signals are propagating outside your building where they don’t
belong, either
✓ Turn down the transmit power setting of your AP.
✓ Use a smaller or different antenna (semidirectional or directional) to
decrease the signal.
Some basic planning helps prevent these vulnerabilities.
Vulnerable wireless workstations
Wireless workstations have tons of security vulnerabilities — from weak
passwords to unpatched security holes to the storage of WEP and WPA