[tor-bugs] #4822 [Tor Client]: Avoid vulnerability CVE-2011-4576 : Disable SSL3?

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#4822: Avoid vulnerability CVE-2011-4576 : Disable SSL3?
------------------------+---------------------------------------------------
 Reporter:  nickm       |          Owner:                    
     Type:  defect      |         Status:  needs_review      
 Priority:  critical    |      Milestone:  Tor: 0.2.1.x-final
Component:  Tor Client  |        Version:                    
 Keywords:              |         Parent:                    
   Points:              |   Actualpoints:                    
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Comment(by rransom):

 Replying to [comment:6 rransom]:
 > Replying to [comment:5 rransom]:
 > > This needs to be tested to determine whether a server which uses
 `TLSv1_method` can receive a connection from a client which uses
 `SSLv23_method`.  (When I read the OpenSSL documentation for those, it
 sort of hinted that that would not work.)
 >
 > BZZZT!  Wrong.  The documentation (`SSL_CTX_new(3ssl)`) says quite
 explicitly that that will not work:

 That chunk of documentation is out of date for clients using OpenSSL 1.0.0
 or later.  From the CHANGES file:
 {{{
  Changes between 0.9.8n and 1.0.0  [29 Mar 2010]
 }}}
 {{{
   *) If no SSLv2 ciphers are used don't use an SSLv2 compatible client
 hello:
      this allows the use of compression and extensions. Change default
 cipher
      string to remove SSLv2 ciphersuites. This effectively avoids ancient
 SSLv2
      by default unless an application cipher string requests it.
      [Steve Henson]
 }}}

 But I expect that clients using `SSLv23_method` still won't be able to
 connect to servers using `TLSv1_method`.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/4822#comment:25>
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