Wireless Security

Question 1

WPA

Answer 1

• Wi-fi Protects Access
• Designed to fix critical vulnerabilities in WEP (Wired equivalent privacy) Standard
• Uses RC4 stream cipher to encrypt traffic, but add TKIP (Temporal Key Integrity protocol) to mitigate types of attacks again WEP
• Neither WPA or WEP are secure enough to be used anymore

Question 2

WPA2

Answer 2

• Used AES ( Advanced Encryption standard) and CCMP (Chaining Message Authentication Code Protocol)
• AES replaced RC4 and CCMP replaced TKIP
• Weaknesses have been found in WPA2 which led to WPA3

Question 3

PSK

Answer 3

Pres-Shared Key

• Means of personal wi-fi authentication
• Uses passphrase to generate key that is used to encrypt communications
• Group authentication
• Admin configures passphrase of between 8 and 63 characters
• This is converted to type of hash value PMK (pairwise master key)
• Same secret must be configured on APs and nodes
• All types of PSK authentication are vulnerable to attacks that attempt to recover passphrase
• Should be at least 14 characters long to mitigate cracking risk

Question 4

WPA3 Personal Authentication

Answer 4

• Uses PAKE (Password Authentication Key Exchange)

- SAE (Simultaneous Authentication of Equals) protocol replaces 4 way handshake

Question 5

WPA Enterprise Authentication

Answer 5

• Use 802.1X and EAP to authenticate against network directory
• EAPoW (EAP over Wireless) forward authentication data without allowing other types of network access
• WPA2 or 3 Enterprise
• When association is requested, AP allows EAPoW traffic only
• Passes credentials to AAA(Radious or TACAS+) server for validation.
• Upon authentication, MK (Master key) is transferred to supplicant
• PMK is generated by both and then four-way handshake or SAE is used to creat session keys

Question 6

Encryption Protocol Mismatch

Answer 6

• Connections will fail even if correct credentials are supplied
• Check that client can support encryption and authentication standards configured on AP
• Driver or OS updates may be needed

Question 7

Disassociation Frames

Answer 7

• Notifies other parties that connection has ended

- Possible indicator of malicious attack

Question 8

Open Authentication

Answer 8

• Client is not required to authenticate
• Used for Public APs or hotspots
• For WPA/WPA2 data is unencrypted
• Can be combined with captive portal or splash page

Question 9

Captive Portal issues

Answer 9

• Arise when redirection does not work
• Portal should use HTTPS
• Most modern browsers block redirection to sites without TLS
• Portal also need to be installed with digital certificate by Certificate authority that is trusted by browser