No firewall, hacking threat?

[DuganRun]

Hello Forum, this is my first post but unfortunately at a worrying time, recently (past two weeks) a certain somebody with excellent computer knowledge and a grudge against me has been making attempts to hack my computer (I've been told this from a reliable source).

So far they've managed to gain access to my email account (Yahoo) as my password was rejected, I managed to get back in through security questions and deleted the account but not before checking the log activity and seeing somebody had been logging into my browser, after I did this my internet connection has been mysteriously dropping out and after speaking with my service provider they say my connection has been dropped 30 times today and it's possible that somebody could have been dropping my connection somehow by using my IP address, since then my informant has told me IP abuse is one of his tricks.

My computer is a macbook running OS X 10.6 and I'm connected via a wireless router, I've checked my computer for viruses with ClamXav and it seems fine but unfortunately today I've noticed my firewall hasn't been turned on, is it possible I've been hacked and if so what kind of information could this person pull from my computer?

Hacker has not had physical access to my computer, just a skype link and knowledge of my email, please help, one very worried mac user, thanks.

 

[GGJstudios]

Any email account password can be hacked without any access to your computer. Make sure your wireless network is protected by a long and complex WPA2 password that you change periodically. The Mac OS X firewall is disabled by default. You should enable it. There are no Mac OS X viruses in the wild, but there are a handful of trojans that usually require that the user install them.

Macs are not immune to malware, but no true viruses exist in the wild that can run on Mac OS X, and there never have been any since it was released over 10 years ago. The only malware in the wild that can affect Mac OS X is a handful of trojans, which can be easily avoided by practicing safe computing (see below). Also, Mac OS X Snow Leopard and Lion have anti-malware protection built in, further reducing the need for 3rd party antivirus apps.

Mac Virus/Malware FAQ​

1. Make sure your built-in Mac firewall is enabled in System Preferences > Security > Firewall
   
   
2. Uncheck "Open "safe" files after downloading" in Safari > Preferences > General
   
   
3. Disable Java in your browser (Safari, Chrome, Firefox). This will protect you from malware that exploits Java in your browser, including the recent Flashback trojan. Leave Java disabled until you visit a trusted site that requires it, then re-enable only for the duration of your visit to that site. (This is not to be confused with JavaScript, which you should leave enabled.)
   
   
4. Change your DNS servers to OpenDNS servers by reading this.
   
   
5. Be careful to only install software from trusted, reputable sites. Never install pirated software. If you're not sure about an app, ask in this forum before installing.
   
   
6. Never let someone else have access to install anything on your Mac.
   
   
7. Don't open files that you receive from unknown or untrusted sources.
   
   
8. For added security, make sure all network, email, financial and other important passwords are long and complex, including upper and lower case letters, numbers and special characters.
   
   
9. Always keep your Mac and application software updated. Use Software Update for your Mac software. For other software, it's safer to get updates from the developer's site or from the menu item "Check for updates", rather than installing from any notification window that pops up while you're surfing the web.

That's all you need to do to keep your Mac completely free of any Mac OS X malware that has ever been released into the wild. You don't need any 3rd party software to keep your Mac secure.

It is extremely rare for an average Mac user to have their computer hacked, unless you give someone access to it. Of all the "I've been hacked!" threads I've seen over the years, not a single one was really hacked.

 

[DuganRun]

Thanks GGJstudios great advice that I will use in the future but I fear it's a little too late in my case, could somebody please try to answer my thread more specifically? thanks again Forum.

 

[GGJstudios]

Thanks GGJstudios great advice that I will use in the future but I fear it's a little too late in my case, could somebody please try to answer my thread more specifically? thanks again Forum.

I did answer it specifically. What question remains that my post didn't address?

 

[DuganRun]

I did answer it specifically. What question remains that my post didn't address?

Sorry GGJ, I missed your last two paragraphs, my mind isn't where it should be at the moment.

You addressed all but could you now let me know your opinion on somebody having my IP address and potentially doing harm with it? my internet service provider is now sure that after tests my disconnection problems are from somebody using my IP address and I'm certain who that person is.

I am very close to closing my contract and line with my service provider and starting a new one in order to get a fresh line again, in so many words they said that wasn't a bad idea.

The guy giving me these problems is some kind of computer security consultant with a telecommunications company, I've just started dating his ex wife and he's a control freak with a lot of computer security knowledge, maybe a little too much information but I'd like you better to understand my situation so I'm possibly not seen as an over paranoid "I've been hacked" poster, I've read so many of those today before I decided to join this forum so I understand your position on matters like this.

 

[GGJstudios]

You addressed all but could you now let me know your opinion on somebody having my IP address and potentially doing harm with it?

Your IP address is not private. Whenever you visit a website, your IP address is how that site distinguishes your computer from others that are also visiting the site. This is plainly visible with sites like whatismyipaddress.com. There's not much, if anything, that most people can do with your IP address.

Seriously, if you keep your firewall on and practice the safe computing steps listed earlier, I don't think you have anything to worry about. If you have any proof that the person has done anything to you, I would contact his employer and let them know. One other thing to remember is that there are a lot of people who claim they have advance "computer security knowledge", or call themselves hackers when the truth is, they're just trying to sound important, and their computer knowledge isn't as advanced as they claim.