Re: ssh advirsory

From: csegat_private
Date: Wed Jun 09 1999 - 12:19:56 PDT

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    On Wed, 9 Jun 1999 altellezat_private wrote:
    
    > 	Details
    >
    > 	when a ssh client connects to the daemon it has a number ( default
    > 	three ) of attempts to guess the correct password before
    > 	disconnecting if you try to connect with a correct login, but
    > 	you only have once if you try to connect with a no correct login.
    >
    > 	EXAMPLE
    >
    > 	alfonso is not user ( login ) in 192.168.0.1
    > 	
    >
    > 	$ssh 192.168.0.1 -l alfonso
    > 	alfonso's password: <hit ENTER key>
    > 	
    > 	Disconnected; authentication error (Authentication method disabled.).
    > 	$
    >
    > 	altellez is user ( login ) in 192.168.0.1
    >
    > 	$ssh 192.168.0.1 -l altellez
    > 	altellez's password: <hit ENTER key>
    > 	altellez's password:
    >
    > 	Now the remote attacker known that altellez is a true login in
    > 	192.168.0.1
    >
    > 	QUICK FIX
    >
    > 	Edit the file sshd2_config (usually at /etc/ssh2), set the value
    > 	of "PasswordGuesses" to 1.
    > 	
    > 	I only has tested it with ssh-2.0.12
    
      I just tried that error with ssh-2.0.13. It was more strange..
    
    
      --- [ unexistant user `unknown' ]
    
      local:~> ssh -lunknown 192.168.0.1
    
      Disconnected; authentication error (No further authentication methods available.).
      local:~>
    
     --- [ existant user `me' ]
    
     local:~> ssh -lme 192.168.0.1
     me's password: [<ENTER>]
    
     Disconnected; authentication error (Authentication method disabled.).
     local:~>
    
    --
    Delete yurself, you got no chance to win.
    



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