How to violate
user’s privacy
Ran Bar-Zik
Developer at Verizon
Media
Journalist at Haaertz
Contact me at:
Twitter: @barzik
internet-israel.com
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Legal information
▪ The Israeli Law
▪ GDPR
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Why we learn it
▪ We are evil
▪ We want to protect ourselves and others
▪ We want cheap prices
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Setting the stage
We track on website only, assuming that domain is
under my control.
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For example
Facebook, your friendly social network
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This is how we are being
tracked on global scale
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Track method 1:
Cookies
LAAAMMMMEEEE
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1. Sent in every request.
2. Persistent.
3. Easy to detect :(
4. Easy to delete :(
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Enters the forever
cookie
ALSO LAAAMMMEEEE
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RESPAWNThe HOLY GRAIL
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Remember: No good deed goes unpunished
Track method 2:
Cookieless
cookies
No cookie no cry
2.
Etag cookie
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LET’S EXPLOIT
IT
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How it works
1. Server sends the session value with etag.
2. User from now on send along If-None-Match.
3. No cookie and still `If-None-Match` header? Tsk tsk tsk
respawn commenced!
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How it can be defeated?
1. Disable all cache by dev tools.
2. Use incognito.
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HSTS cookie
How it can be defeated?
1. Use incognito.
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DNS cookies
See which request is being sent to DNS server and
then measure it. http://dnscookie.com/
How it can be defeated?
1. VPNTOR
2. Clear DNS cache
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Track method 3:
IP
LAAAMMMMEEEE
3.
How it can be defeated?
1. VPNTOR
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Track method 4:
WebRTC
4.
ifconfig | grep "inet " | grep -v 127.0.0.1
WebRTC exposes
Internal IP
1. ifconfig | grep "inet " | grep -v 127.0.0.1
2. https://ip.voidsec.com/
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How it can be defeated?
1. VPNTOR + Disable WebRTC
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Track method 5:
Fingerprinting
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https://amiunique.org/fp
How it is being
used
Gather the info Create hash Implement it
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How it can be defeated?
1. No current way
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Track method 6:
Social Fingerprinting
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https://robinlinus.github.io/socialmedia-leak/
How it can be defeated?
1. Use incognito
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Track method 7:
Password tracking
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https://senglehardt.com/demo/no_boundaries/loginmanager/index.html
How it can be defeated?
1. No actual way, sorry guys.
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Remember
Only one breach is needed
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Ran Bar-Zik : @barzik
▪ Follow me on Twitter, FB, Telegram
▪ My website: internet-israel.com
▪ Also at Haaretz
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How to track users