[tor-bugs] #17207 [Tor Browser]: Testing navigator.mimeTypes for known names can reveal info and increase fingerprinting risk

[Tor Bug Tracker & Wiki]

#17207: Testing navigator.mimeTypes for known names can reveal info and increase
fingerprinting risk
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     Reporter:           |      Owner:  arthuredelstein
  TemporaryNick          |     Status:  assigned
         Type:  defect   |  Milestone:
     Priority:  major    |    Version:
    Component:  Tor      |   Keywords:  tbb-fingerprinting,
  Browser                |  TorBrowserTeam201510
   Resolution:           |  Parent ID:
Actual Points:           |    Sponsor:
       Points:           |
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Comment (by arthuredelstein):

 Replying to [comment:7 gk]:
 > Good stuff! I thought we already had a defense against this but I could
 not find anything so far.

 It's interesting that `navigator.mimeTypes.length == 0`. So one would have
 thought it didn't have any members.

 > Arthur: do you have some spare cycles to look at this in October? I fear
 all the other TBB people are busy with deadline work...

 Yes -- I'll try to look at this soon.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/17207#comment:9>
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