Posted 16 June 2016 - 11:36 AM
Thanks for taking the time to read this.
To begin: I share a wifi network at work with a separate office. Recently, I came into work and noticed that the settings on my computer monitor had been tampered with. Someone had 100% physically been messing with my office computer.
The guy who works in the other office is a person I'm deeply suspicious of and his behaviour recently has been highly unusual.
So I started getting a lot of warnings from Norton anti-virus about malware etc. This made me suspicious enough to check the installed programs list and sure enough, there's a 1GB program I DID NOT install pretending to be "PokerStars". I checked the size of the genuine pokerstars software online and it's 250mb...besides which, I did not install *anything* on the day in question.
I saved all the logs from the Event Log section then reinstalled Windows from scratch. Wiped the whole thing to factory settings.
A day or two later the guy I think is tampering with my computer gets his secretary to ask me if I've had problems with email login for outlook. This in itself is highly irregular as, quite simply, we cannot stand each other and would never have any contact. I barely say hello to him- he's devious and dangerous. This question from his secretary was clearly, to my mind, him fishing for info after realising his attempt to hijack my work PC had backfired.
So after the re-installation I check all the event logs again and there are far less warnings listed. I know very little about this stuff but the immediate difference was that the failed security audit warnings had stopped. Then, out of the blue, I see the command prompt screen flash up for a millisecond and vanish again. This has never ever happened.
So to summarise:
1. 100% physical tampering certainty where screen was concerned
2. The wifi router is in this guy's office
3. A 1GB program installed on my PC which I 100% did not put there
4. Malware warnings from Norton
5. Command screen pop-up for first time ever, even after fresh install of Windows
A final 6 is that in my Outlook mail I noticed this week a folder called "Migrated Mail" which I don't ever remember using. It's not a standard folder and it looks to me like someone has tried to migrate our office mail. I strongly suspect he did that.
So here's my question and I'm praying one of you can help:
Given I have to share the wifi with this guy, how can I make absolutely certain nothing is being done to hack my PC over the network? From what I've read, he can use software to basically grab all our bank account logins, etc. I have no trust for this guy whatsoever and I've spoken to my line manager to tell him all of this. For this guy to get his secretary to ask me some stupid question about his supposed problems signing into his email was the last straw for me- I asked him if he needed to use my computer and his reaction was a panicked denial that was over the top- "I didn't go near your computer! Why would I use your computer?!" , when that wasn't even what I asked him.
I know the obvious solution is to get the phone company to install a separate phone line and stop sharing the wifi with this guy but short of that I would actually like to catch him in the act. I do not think his tampering with our PC is a simple matter of being nosey; I think he's up to something criminal.
In the short-term, how do I lock down this PC to stop someone listening to data over the shared network? I've read about ports and "sniffing" but how do I check if this is happening and block it?
If I'm right, is this LAN hacking thing easy enough for him to do? And how do I prove it's him that's doing it?
Am I better off to install a Linux operating system? If so, which one and what settings etc would prevent any hacking attempts over the LAN? Nobody else uses that broadband line apart from my office and his.
I know this is a broad topic and I know it's obvious I'm no expert, but please would someone tell me what I should be doing.