Wireless Security 101

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High-End Computing in the Cyber World Pitfalls
of Wireless Networking Lawrence Hale Director,
Federal Computer Incident Response Center
(FedCIRC)
March 27, 2003
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Why Wireless? WLAN Case StudyIncreased
Productivity at Microsoft

• Campus-wide Cisco Aironet installation
• Actively used by 40,000 employees
• 30 minute productivity gain per employee per
  day

• Minutes gained working at the beginning of slow
  starting meetings
• Eliminates Ill do it when I get back to my
  desk syndrome
• Instant Messaging allows for getting answers
  without disturbing meetings
• Can send all participants (conf. call too)
  presentation so they can view it simultaneously
  without a projector

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Why Wireless?

• Wireless systems can provide inexpensive network
  redundancy.

Properly designed, a wireless broadband
network can be flexible, scalable, and customized
enough to offersolutions from a mirror image
voice/data hot standby network to a single
diverse private line connecting to a primary
carrier.
Disaster Recovery Journal Winter 2003
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Basic Wireless LAN

• Access points connected to the wired
  infrastructure broadcast radio waves that are
  picked up and connected to by Client Network
  Interface Cards.

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Wireless Service Set ID (SSID)

• An identity-based verification mechanism that
  can be accessed by users who provide it with
• The proper shared cryptographic key
• The proper network SSID
• An empty string in place of the SSID

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Wireless Standards

• 802.11b Wireless Fidelity (Wi-Fi)
• 2.4GHz, 11(6) Mbps, 3 Channels, Lower Cost, Lower
  Power (important for handhelds)
• 802.11g-2
• 2.4GHz, 54Mbps (High throughput upgrade from
  802.11b that is fully forward/backward compatible
  with 802.11b)

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Threats to your wireless LAN
Theft of equipment
Unauthorized access
Acts by malicious users
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WLAN Vulnerabilities

• All the vulnerabilities that exist in a
  conventional wired network
• Lack of physical security and standard default
  settings
• The inability to authenticate Access Points
• Sensitive information that is not encrypted
• Handheld devices are easily stolen and can
  reveal sensitive information
• Data may be extracted without detection from
  improperly configured devices

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WLAN Security Threats
Attacks
Passive Attacks
Active Attacks
Message Modification
Denial-of- Service
Eavesdropping
Traffic Analysis
Masquerade
Replay
Taxonomy of Security Attacks NIST Wireless
Network Security pub. 800-48
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Wireless Intrusion Detection Tools

• Netstumbler Spyglass (NSS)
• AirSnort
• Internet Security Systems Wireless Scanner

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To Mitigate WLAN Risks

• You Should
• Strategically place and tune Access Points (APs)
  so that wireless coverage is only available where
  needed
• Have firewalling and router ACLs between the APs
  and the internal wired network
• Use encryption between wireless nodes and wired
  nodes
• Install Intrusion Detection tools on the wired
  side of the APs

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To Harden Your WLAN

• You Should
• Educate
• Be sure all System Administrators, Managers and
  End Users are Aware
• Change the default SSID settings
• Utilize encryption methods

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The Future of Wireless is

• NOW since 802.11 technology has gone mainstream
• Inexpensively increasing employees productivity
• Likely to increase as Access Points extend wired
  networks
• Important to understand in order to maintain
  availability, integrity and confidentiality of
  information systems and their data

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Recommendations

• Allow business needs to determine
  implementations
• Ensure policies are established
• Ensure procedures are enforced
• Eliminate default passwords
• Use available technical controls
• Identify devices with wireless functionality
• Utilize network discovery tools for Configuration
  Management (including discovery of rogue devices)
• Due to the frequency and complexity of changes in
  the wireless arena, ongoing education is vital

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Contact Information
Lawrence Hale Director, Federal Computer Incident
Response Center (FedCIRC) (202)
708-7000 www.fedcirc.gov