[tor-relays] 90% of exits vulnerable to TCP off-path attack

[isis agora lovecruft]

starlight.2016q3 at binnacle.cx transcribed 1.2K bytes:
> At 12:01 8/12/2016 -0400, Zack Weinberg wrote:
> >Also, if you read the paper, raising the global rate limit (as
> >suggested by the reg. article) doesn't help; it only slows the
> >attacker down a little.
> 
> The paper indicates that a global counter limit other than
> 100 can be easily discovered.  However the recommended
> mitigation effectively removes the global counter by setting
> it to 10^9.  The described attack requires the counter
> be exhausted inside the temporal bounds of one second and the
> Internet as it exists today cannot support 10^9 probes on
> that deadline.
> 
> IMO the recommended mitigation is effective and should
> be applied by those believing RFC-5961-as-presently-
> implemented changes worse than the weaknesses addressed
> by the RFC.  I applied the mitigation.

Hello,

Apparently, my last email to the list went to your spam folder.  Please allow
me to repeat myself:

isis agora lovecruft transcribed 4.5K bytes:
> The accepted patch [1] solves the issue, and does so by randomising the time
> window that the global variable applies to.
>
> [1]: https://github.com/torvalds/linux/commit/75ff39ccc1bd5d3c455b6822ab09e533c551f758

Best regards,
-- 
 ♥Ⓐ isis agora lovecruft
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