As a temporary solution you could use my ssh bruteforce preventing script
of iptables

I use this to prevent ssh and ftp bruteforce where AAA.BBB.CCC.DDD is your
trusted ip, which never will be blocked. This script will block ip, if it
make >3 connections per 5 minute.

iptables -N SSH_WHITELIST
iptables -A INPUT -p tcp --dport 22 --syn -m recent --name sshbr --set
iptables -A INPUT -p tcp --dport 22 --syn -j SSH_WHITELIST
iptables -A INPUT -p tcp --dport 22 --syn -m recent --name sshbr --update
--rttl --hitcount 3 --seconds 300 -j REJECT --reject-with tcp-reset
iptables -A SSH_WHITELIST -s AAA.BBB.CCC.DDD -p tcp --dport 22 --syn -m
recent --rttl --remove

To increase security change MaxAuthTries 1 in /etc/ssh/sshd_config, so
remote user can do only 2 connection attempts with 2 password retries.

On Thu, Dec 29, 2011 at 4:33 PM, Ville Tiensuu <[email protected]> wrote:

> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Hello,
>
> Could you please paste /var/log/auth.log message of attack?
> Are you sure about it's not any bruteforce attack or similar?
> I think the problem is not in SSH server itself, it's in your server's
> security. Are you using weak password, and allowing direct root access
> to the server via SSH?
> If problem persists in your other servers, try to use fail2ban or similar.
>
> - -Ville
>
> 29.12.2011 16:04, Taz wrote:
> > Hello, we've got various debian servers, about 15, with different
> > versions. All of them have been attacked today and granted root
> > access. Can anybody help? We can give ssh access to attacked
> > machine, it seems to be serious ssh vulnerability.
> >
> > How can i contact openssh mnt?
> >
> > Thank you.
> >
> >
>
> -----BEGIN PGP SIGNATURE-----
> Version: GnuPG v2.0.17 (MingW32)
> Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/
>
> iQEcBAEBAgAGBQJO/HokAAoJEFg15w+Y7E/mDL0IAItgyj5TSWgTILUE7l/cF7PS
> BwG71ypgQf/uMlsNnkbylspnvBj9edZfKfer844NvrG6yJbLw25sNI4eOLlvO1xQ
> nQJHwSNPhWVRHt3gwu5QlHSv0r0qbBdcXjQXDwqG6adp8qY3Qx7BIzvU0DThb08K
> Kbk0/4WcUHb7GtphJUIENPnyaC6xksb413fyT2RW3/m3xm7bRWqXH5bSAvs4/NIP
> 1m9oqxPO+HNnTF1U1KV+fdubLGIYeMHrskKSubBQ7U/+mn7/uhANT6Ke4XFtWsu8
> Mgwr11j2/trCTxBNJvAEyjdpK2/vn+LRgNF12THOeCVFNQcgVyY+iWwGddY6IyU=
> =8DkS
> -----END PGP SIGNATURE-----
>
>
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-- 
BR, Nikolay Yatsyshyn

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