Ubuntu server Hacked using openssh client connection

I had configured a Linux webserver based on a ubuntu server 10.4. On the other hand the host was debian squeeze in which the ssh port open. From mac there was a ssh connection . It was for to monitor the logs.The vm as well as mac which is running OS X lion were on the same network.

Today i have noticed that my Terminal.app permission shave been set to deny execution, and other binary permissions have been reset. Due to this there was no choice for me to fix it apart from format and re-install. I am no longer able to replace them. Was there anything bad happened?

you've already logged in as root ssh on your ubuntu server? So you have activated the root account in ubuntu when it is inactive by default? if you try to log in with your normal user it does not work either?

A relatively unknown feature of openssh present time is its ability to create a VPN tunnel. In this context, is meant a real tunneling tunneling level-3 (IP over SSH), and not the 'SSH forwarding which is often referred to incorrectly as SSH tunneling. In this case, you create a new virtual network interface, can be used like any other. This mechanism is much more powerful and flexible than simply forwarding and can be used in addition to TCP, UDP and even ICMP. Once established, the VPN allows the forwarding of traffic between two remote networks, or at least distinct, through an SSH connection.

Unlike telnet, ssh does not transfer the information in clear text over the network, but encrypts them beforehand.

I discovered that the false exploits open-ssh "0day" magically appeared a few days ago, had already made. the first appearance in mid-July 2009 under the name of OpenOwn.c.