telnet vs ssh on Core equipment , looking for reasons why ?

alex at yuriev.com alex at yuriev.com
Tue Jul 31 15:14:30 UTC 2001


> > Pardon for blowing your bubble but sniffing ssh keyexchange does not do you
> > any good. The symmetric key is exchanged via a channel aready secured. The
> > keys that is used to secure the channel used to exchange the symmetric key
> > are exchanged via DH-based protocol. If you want to spend your time
> > factoring primes for next 500 years to extract the key, you are more than
> > welcome to try. It is crypto-101.
> 
> If you can arp spoof as indicated in the message you are replying to, you
> can perform a MTM attack which SSH offers only minimal security against
> (in the form of stored host keys that users often choose to ignore or not
> verify the fingerprint). Look to SRP for a MTM-less password
> authentication solution.

Monkey in the Middle attack on SSH is very difficult to perform. I'm cc'ing
Matt Bishop (bishop at cs.ucdavis.edu) who together with yours truly wrote a
paper on this in 1997. 

Cheers,
ALex




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