[tor-bugs] #7179 [EFF-HTTPS Everywhere]: Ths SSL Observatory feature leaks DNS requests without the TBB

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#7179: Ths SSL Observatory feature leaks DNS requests without the TBB
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 Reporter:  gk                    |          Owner:  pde
     Type:  defect                |         Status:  new
 Priority:  critical              |      Milestone:     
Component:  EFF-HTTPS Everywhere  |        Version:     
 Keywords:                        |         Parent:     
   Points:                        |   Actualpoints:     
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 HTTPS-Everywhere is leaking DNS requests no matter whether I use Tor or
 not (but note that the TBB is not affected. See below for the reason). All
 tests were made in a clean new profile with FF 16.0.1 and HTTPS-E 3.0.2
 installed.

 The reason is that

 Ci.nsIProxyInfo.TRANSPARENT_PROXY_RESOLVES_HOST

 is _not_ enough to be sure to not leak DNS requests if you build your
 proxy settings manually and using applyFilter(). This is actually a
 Mozilla (Necko) bug documented here:

 https://bugzilla.mozilla.org/show_bug.cgi?id=536093

 The only workaround I am currently aware of is setting
 "network.dns.disablePrefetch" to |true|, a thing which is done in the TBB.
 Then there are no requests leaking.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/7179>
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