OSX Security

You suspect malware is hogging your bandwidth? What is your data cap? what kind of the things do you do online daily?

 

If you have a Mac virus or worm that's using a ton of bandwidth, unfortunately you're the first to get it, so there's no AV program that can help.

As suggested, try the Little Snitch utility. It should make you aware of literally every program on your Mac that attempts to use the network.

 

There are still zero viruses for Mac OS X in public circulation.
Other kinds of malware, like trojans, need to be installed by the user of the Mac manually.

Mac Virus/Malware Info by GGJstudios
There are currently no viruses for Mac OS X in public circulation, only a handful of trojans and other malware, which have to be installed manually via entering the administrator password.
The only anti-virus you need to protect your Mac is education and common sense.​

 

You never know with those elderly people

Maybe it's because your uploading too much? we we're always going over the limit, not because of downloading, but because of uploading.

And maybe youtube is the killer. But yes with Little Snitch you'll find out.

 

Is your WiFi secure? try setting up MAC filtering on your router to make sure you're the only one using it.

 

Do you use off site backup like Crashplan? Uploading your entire hard drive could blow through any caps pretty quickly.

Do you have mobile me? If you do, disable back to my mac just to make sure somebody isn't stealing your bandwidth by knowing your mobile me password and running stuff on your machine remotely. Also MobileMe syncs some files across machines and might push a lot of data up to the net if you have all its sync features turned on. Check those as well.

I also recommend little snitch but I must admit it can be a pain. It pops up absolutely every time a new program asks for net access and can get old pretty quick. Of course the alternative is not knowing what's going on so I put up with it.

Before bothering with mac filtering, perhaps you can set up a new (hidden) ssid and wpa password for your wifi. Anybody that was stealing it will no longer be able to get at it. Of course this means changing settings on all your machines but at least you will know nobody can get in the new ssid right away.