Let's say you have a server at a data centre, but a hacker manages to find a way in and has access to your server. What are the attack possibilities with all the interfaces available?
Are there any known attack and defence mechanisms to a system once physical access has been gained?
Think about VGA, USB, Firewire, IPME and BMCs.
Running Ubuntu 16.04.
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The question is a bit broad, however, I am hoping for practical answers, such as:
The answer provided is not exactly what I am looking for, since the top answer is: "The attacker can do everything". I am hoping for more in-depth (practical) answers of the possibilities are of 'everything'.