Welcome to the most active Linux Forum on the web.
Go Back > Forums > Linux Forums > Linux - Newbie
User Name
Linux - Newbie This Linux forum is for members that are new to Linux.
Just starting out and have a question? If it is not in the man pages or the how-to's this is the place!


  Search this Thread
Old 09-26-2017, 05:20 PM   #1
Senior Member
Registered: Nov 2011
Location: London, UK
Distribution: Debian
Posts: 1,823

Rep: Reputation: 429Reputation: 429Reputation: 429Reputation: 429Reputation: 429
Is this a SSH bug?

I have only just re-installed openssh & client, rebooted the PC.
I have given it no keys - although there may be some old public keys present.
Just to see what would happen, expecting it to fail
jeremy@hector ~ $ ssh hector
. But it opened a session on my PC like normal
host ECDSA key for IP address '' not in list of known hosts.
Linux hector 3.16.0-4-amd64 #1 SMP Debian 3.16.43-2+deb8u5 (2017-09-19) x86_64

The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
Last login: Tue Sep 26 21:43:04 2017
jeremy@hector ~ $ logout
Connection to hector closed.
Have Debian removed host ECDSA key from their list of identifiers?
Old 09-26-2017, 07:43 PM   #2
Registered: Aug 2002
Posts: 21,003

Rep: Reputation: 3872Reputation: 3872Reputation: 3872Reputation: 3872Reputation: 3872Reputation: 3872Reputation: 3872Reputation: 3872Reputation: 3872Reputation: 3872Reputation: 3872
Not a bug.

When you reinstalled ssh it created a new host key i.e. /etc/ssh/ssh_host_ecdsa_key... The host key prevents man in the middle attacks and is stored in your ~/.ssh/known_hosts file. This is the reason for the "host ECDSA key for IP address '' not in list of known hosts." warning message.

I would of expected an error since the key changed but had the same IP address.

Reinstalling the client does not delete the .ssh directory and since your public/private key file are stored in your users ~/.ssh directories on server/client they should still be valid and as posted you were logged in.
1 members found this post helpful.


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
[SOLVED] I think i found a bug in Ssh server guarapo Linux - Security 4 01-23-2010 08:38 AM
Ssh Bug Server Problem Devanshu Kumar Singh Linux - Newbie 4 01-16-2008 01:19 AM
ssh exit hang, not Bug#52 Linux - General 5 01-26-2007 06:41 AM
OpenSSH ssh-agent problems. Bug? darklogik_org Slackware 2 02-10-2004 06:25 PM
Keychain ssh problem (bug????) pcwulf Linux - Security 3 11-27-2003 11:55 PM > Forums > Linux Forums > Linux - Newbie

All times are GMT -5. The time now is 06:09 AM.

Main Menu
Write for LQ is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration