[tor-bugs] #15463 [Tor]: TOR CPU load 100%. Hidden service unavailable. Maybe zero-day vulnerability like "circuit storm".

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#15463: TOR CPU load 100%. Hidden service unavailable. Maybe zero-day vulnerability
like "circuit storm".
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     Reporter:  alberto   |      Owner:
         Type:  defect    |     Status:  new
     Priority:  critical  |  Milestone:
    Component:  Tor       |    Version:
   Resolution:            |   Keywords:
Actual Points:            |  Parent ID:
       Points:            |
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Comment (by alberto):

 1) It's not very busy hidden service. 10-20-30 users at site online. Count
 of users to site- no increased in last time.
 In normal work- when I enable debug- his size- maybe 5-10Mb in few
 minutes. Now- I enable debug- his size 250mb in 2 minutes.
 Earlier server never has problems like this. TOR get 0.3-3% of CPU.
 2) I try make logs with required for you information in next 1-2 hour.
 3) Already trying set CloseHSServiceRendCircuitsImmediatelyOnTimeout 1 on
 torrc. No changes in CPU load(100% in few seconds). Hidden service not
 work.
 Attack to name of this service. When he disabled- another hidden services
 work without problems and TOR not overload CPU.
 But when work attacked service- all another HDS too practically down.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/15463#comment:5>
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