2600 Presentation on wireless security in 2016. Originally presented at Rochester 2600.

1. 8/6/16
The State of WiFi Security
Another presentation in the
“Why specifically does it suck”
seminar series

2. 8/6/16
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Open
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WEP
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WPA
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WPA2
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WPA2 Enterprise
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…?

3. 8/6/16
WEP is dead lets not talk about it

4. 8/6/16
WPA vs WPA2
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Auth: TKIP (RC4)
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Cipher: RC4
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Enterprise: EAP, TKIP,
RC4
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CCMP (AES+MAC)
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AES (optionally RC4)
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EAP, CCMP, AES

5. 8/6/16
WPA and Rainbows
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Can you make WPA rainbow tables?
– Yes but you’d be an idiot
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Why?
– Glad you asked!
– WPA[1,2] takes a string as the password and salts it with the SSID
– “password” + “Linksys” == “passwordLinksys”
– Actually this is how you make the pair-wise master key
pwmk = PBKDF2(HMAC-SHA1, “password”, “Linksys”, 4096 rounds, 256
bit)
– Therefore, only pre-compute words for common SSIDs

6. 8/6/16
Latest Rage
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Shared Wifi: “We are all secure because we
have WPA2 and a strong password”
– WRONG

7. 8/6/16
Demo?
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Play along at home:
http://www.lovemytool.com/files/test.pcap
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Precompute WPA key
– https://www.wireshark.org/tools/wpa-psk.html
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Open wireshark preferences
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Got to IEEE 802.11 and add key
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…
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Magic

8. 8/6/16
Old Rage
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“Well I use HTTPS and that’s just passive
interception”
– Mostly true
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We still have ARP and DHCP and DNS servers
that are skiddy hackable
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Can’t trust any shared networks

9. 8/6/16
Example: Interlock
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Interlock-Members:
Password changes every 2
years at most, everyone
knows the password
– Passive interception and
decryption
– Let me save you some time
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Interlock-Guest: open wifi,
no security

10. 8/6/16
Enterprise Environments
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WPA2 Personal: Everyone gets the same key
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WPA2 Enterprise: Everyone makes their own
key based on their authentication (credentials,
certificate, etc)
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No more wireshark decrypt

11. 8/6/16
Attacking WPA2 Enterprise
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Setup Rogue AP
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Have the client connect to it
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Receive the EAP protected credentials
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Use `asleap` to crack protected credentials

12. 8/6/16
Fuck Defending Enterprise

13. 8/6/16
Defending Home/Hackerspace
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No one wants to maintain a RADIUS server just
to do authentication over wifi
– Ok except for Pee
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A RADIUS service is a target
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What if you don’t care about authentication but
just care about making a single session key?

14. 8/6/16
Setup
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Setup FreeRADIUS server to authenticate your
wireless network
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Add the following lines
– DEFAULT Auth-Type := Accept
– log_auth = yes
– log_auth_badpass = yes
– log_auth_goodpass = yes
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Bonus: This will collect all usernames and
passwords that people enter.
– “Please log in with your Gmail or Yahoo passwords”

15. 8/6/16
Conclusion
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This is super hacky but effective
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WPA crypto primitives are getting old:
– SHA1
– PBKDF2 with only 4096 bit
– No PFS
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WPA is old: 2004
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There are no plans AFAIK to change them
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WPA3: SHA256, PSK, DH temporal key exchange

16. 8/6/16
The Bill Slide
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No, your WiFi isn’t secure enough
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WPA2 Enterprise + EAP + Any username is
more secure
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Google “radius docker wpa” done.
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Tell management that wifi sucks because it
doesn’t have Diffie-Hellman. Seriously.

17. 8/6/16