Subject: Re: telnetd core
To: Wojciech Puchar <wojtek@tensor.3miasto.net>
From: Bruno Saverio Delbono <Bruno.S.Delbono@wf0.com>
List: netbsd-users
Date: 12/29/2002 04:29:49
At 11:57 AM 12/29/2002 +0100, Wojciech Puchar wrote:
>i found telnetd.core in / directory of public access machine that works
>stable for few months.
>
>in logs i found lots (every few seconds) messages like
>telnetd[9872]: ttloop:  peer died: No such file or directory
>
>and lots of messages from inetd about connection to telnetd from many
>different hosts.

It seems that someone is trying to use a NetBSD telnetd exploit by Team 
Teso on your box.

See: http://mail-index.netbsd.org/netbsd-announce/2001/07/25/0001.html

BTW - from the telnetd/utility.c source code:

/* ttloop - A small subroutine to flush the network output buffer, get some 
data
  * from the network, and pass it through the telnet state machine. We
  * also flush the pty input buffer (by dropping its data) if it becomes
  * too full.
*/

>is telnetd exploitable??! any protection?


See above advisory.

Note: You may wish to disable telnetd altogether as it offers no protection 
over ssh.

Regards,

-Bruno

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