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Re: [tor-bugs] #10114 [Tor bundles/installation]: tbb-firefox.exe crashes on startup



#10114: tbb-firefox.exe crashes on startup
-------------------------------------+-------------------------------------
     Reporter:  Lehona               |      Owner:  erinn
         Type:  defect               |     Status:  new
     Priority:  normal               |  Milestone:  TorBrowserBundle
    Component:  Tor                  |  2.3.x-stable
  bundles/installation               |    Version:
   Resolution:                       |   Keywords:
Actual Points:                       |  Parent ID:
       Points:                       |
-------------------------------------+-------------------------------------

Comment (by cypherpunks):

 Something in your box actively modifies code of functions in memory (or
 files). That reminds API hooking.

 Here affected code:
 {{{
 12AD:  E92E450200 ;PR_OpenTCPSocket
 12B2:  E969450200 ;PR_NewTCPSocketPair ;Crash here!
 }}}
 ''PR_OpenTCPSocket'' of ''nspr4.dll'' is known as usual target for hooking
 by various malware/software. Usually it replaces a prologue of target
 function with the ''JMP rel32'' (E9 op.code) so code of next function
 shouldn't to be affected, except this case it seems. If ''JMP d,[addr]''
 (FF25 op.code, 6 bytes) or something another used then code at 12B2 was
 modified and crash as result.

 Browser from tor-browser-2.3.25-8_en-US.exe was compiled with
 optimizations so code of PR_OpenTCPSocket looks like:
 {{{
 4952: 6A01
 4954: 6A02
 4956: E815FFFFFF
 495B: 83C40C
 495E: C3
 }}}
 Enough space for any JMPs there, no another functions modified and no
 crash.

 No more reasonable explanations. Your box infected or some very weird
 software used.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/10114#comment:10>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online
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