[tor-bugs] #7277 [Tor]: timestamp leaked in TLS client hello

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#7277: timestamp leaked in TLS client hello
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 Reporter:  proper      |          Owner:                    
     Type:  defect      |         Status:  new               
 Priority:  normal      |      Milestone:  Tor: 0.2.4.x-final
Component:  Tor         |        Version:                    
 Keywords:  tor-client  |         Parent:                    
   Points:              |   Actualpoints:                    
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Changes (by nickm):

  * keywords:  => tor-client


Comment:

 Interesting idea. Probably this would require an OpenSSL patch.  The
 impact here, if I understand right, would be that the guard (or anybody
 else who can see the initial connection) can probabilistically track a
 client with a skewed clock even as it changes IPs.

 Of course, the set of guards also makes that possible right now, as does
 the NETINFO time, as other stuff probably does too.

 The worse affect of the timestamp in the TLS hello would be the TLS hello
 in application connections sent over Tor.  If TBB can't do anything about
 that, it's a probabilistic linkability issue for skewed clients.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/7277#comment:1>
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