[tbb-bugs] #21559 [Applications/Tor Browser]: Tor browser deanonymization/fingerprinting via cached intermediate CAs

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#21559: Tor browser deanonymization/fingerprinting via cached intermediate CAs
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 Reporter:  cypherpunks                          |          Owner:  tbb-
                                                 |  team
     Type:  defect                               |         Status:  new
 Priority:  Medium                               |      Milestone:
Component:  Applications/Tor Browser             |        Version:
 Severity:  Normal                               |     Resolution:
 Keywords:  tbb-fingerprinting, tbb-linkability  |  Actual Points:
Parent ID:                                       |         Points:
 Reviewer:                                       |        Sponsor:
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Comment (by cypherpunks):

 FWIW:
 1) It's not an ordinary cache, but just a fallback for misconfigured
 servers made for "fixing" issues like #2167, #9479, #18218, #19371, but
 doesn't work as you see, because it's useless for stateless browser and
 should be disabled.
 https://bugzilla.mozilla.org/show_bug.cgi?id=1334485#c11
 2) Mozilla urgently disabled SHA-1 and removed WoSign busters from the
 root.
 https://bugzilla.mozilla.org/show_bug.cgi?id=1311824#c1
 3) PoC successfully stress-tested the network subsystem of Firefox leading
 to potentially exploitable crash. Cache should be disabled to reduce the
 surface and check whether it's the root cause.
 https://bugzilla.mozilla.org/show_bug.cgi?id=1334485#c21

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/21559#comment:5>
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