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I woke up and found my PC switched on. I have wake on LAN enabled.

I check the log and my pc started up an hour after i went to bed. I have very basic windows log reading skills. Is there something I can check to see if something malicious was done? Im going to change passwords and run virus scan. Incidentally my wifes user account on PC has no password. And she has admin rights.

I know this all sounds bad, but I never expected someone could do anything to me. Also yesterday found out my hotmail account was blocked because of spam sent from my email. I have a very strong password on it to and never use third party hotmail checkers.

Update: i use windows 7 pro

Update: I will read the logs more later, but just so you know Im pretty sure it wasnt a scheduled wake, cause i never leave the PC on overnight, and its the first time this has happened since building this machine 10 months ago. I will of course double check.

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My wife had her Hotmail account hacked about a year ago. She's very careful, had a reasonably strong password, and our home network is quite secure. I think Hotmail probably has some inherent insecurity somewhere that makes it more susceptible to hacking. – Daniel R Hicks May 3 '12 at 11:59
@DanH - Unlikely. The only known exploit in the last year which has already been fixed was an exploit that allow you to reset your password BUT there was a social engineering aspect that was required. – Ramhound May 3 '12 at 14:29
@Ramhound -- Like I said, my wife is very careful and very unlikely to be taken in by a "social engineering" exploit. – Daniel R Hicks May 3 '12 at 15:45
@madphp Please run powercfg -lastwake to determine what caused the computer to wake up. – Oliver Salzburg May 3 '12 at 20:28
@Oliver Salzburg Wake History Count - 0 – madphp May 4 '12 at 1:00
up vote 7 down vote accepted

Calm down

It is very unlikely that someone has remotely turned on your computer.

Wake On Lan (WOL), as the name implies, will only work on a LAN. Which means, it won't work over the internet.
This is due to how WOL works. The packets that are sent to wake up a computer aren't forwarded by routers. So, the packets will never travel very far (and especially not over the internet).

OK, so what was it?

This still leaves the question, why was the computer even turned on?

Assuming you're using Windows, there are many way a system can be woken up. Let's have a look into Device Manager:

enter image description here

As you can see, many devices can be allowed to wake the computer up. Like a mouse or a keyboard or a network adapter.

So, if your computer was sleeping and someone (maybe a pet) accidentally touched the keyboard, that can already be enough. But there's more!

You might have a scheduled task (maybe a backup) that is allowed to wake your computer so that it can perform.

enter image description here

What woke up the computer?

Somewhere in the Event Log, it should say if one of those things started your computer. Sadly, I currently lack a proper entry to provide a good screenshot.

But there are many reasons a computer can wake up from sleep that are far from a hack.

To determine why your computer last woke up from sleep, use powercfg:

powercfg -lastwake
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Even when set up to allow WOL over WAN, I'd assume an accidental activation is unlikely. To my understanding, waking a machine always requires knowledge of the MAC address to create the WOL packet. Now, if you've set up WOL over WAN and someone knows your MAC address, then, I guess, it could be a third party. But then it is hardly a hack if you leave the door wide open :) – Oliver Salzburg May 3 '12 at 12:03
I know my laptop will fairly often wake from sleep while closed, unplugged, and in its bag. Windows is a very light sleeper. – Daniel R Hicks May 3 '12 at 12:05
Afraid of security? Then don't use Hotmail... - there's very little you can do to secure your account as Hotmail (although they don't like to admit it) is inherently insecure and widely targetted by exploit 'tools'. – HaydnWVN May 3 '12 at 13:10
@HaydnWVN - What a bunch of hog wash. I have had a hotmail account since it came out, it is exposed and listed in thousands of google results, never once have I been compromised. I have NEVER been compromised on any acount and have been on the internet since 1993. Of course I won't call madphp an idiot for using the same password for everything. – Ramhound May 3 '12 at 14:32
@Ramhound -- The fact that your Hotmail account has not been hacked yet proves nothing. – Daniel R Hicks May 3 '12 at 15:46

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