[tor-bugs] #23969 [Core Tor/Tor]: Scallion/cathugger attack on Tor

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#23969: Scallion/cathugger attack on Tor
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 Reporter:  cypherpunks   |          Owner:  (none)
     Type:  defect        |         Status:  closed
 Priority:  High          |      Milestone:
Component:  Core Tor/Tor  |        Version:
 Severity:  Major         |     Resolution:  invalid
 Keywords:                |  Actual Points:
Parent ID:                |         Points:
 Reviewer:                |        Sponsor:
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Changes (by yawning):

 * status:  new => closed
 * resolution:   => invalid


Comment:

 > This is a possible attack of Tor's hidden service.

 This requires a large but not totally unfeasible amount of work, or
 breaking SHA-1's pre-image resistance.

 > Unfortunately, V3 onion namesystem are already cracked

 Generating a fully colliding v3 onion service address requires a quantum
 computer, and the algorithm to do accelerated ed25519 key pair generation,
 which you're calling an "attack" is even mentioned in the v3 onion service
 spec (Appendix C).

 Closing as invalid, since this does not impact v3 services unless
 adversaries have hardware that's capable of totally breaking all of Tor.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/23969#comment:3>
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