Being remotely harassed

[murmeldjur]

I don't know why and how, but my background is being changed on my computer. I think it is done remotely, and I know it is my colleagues doing this.

I have a freshly bought and installed MacBook Pro (2012 edition), fully up to date.
I have password protection, I switch password every now and then (when being offline, so they can't sniff it). So I am pretty sure they don't know my password.

I have an active Apache server, with PHP enabled and a MySQL database.

The only way we are connected otherwise are through SVN (a version control for files and projects).

How can they somehow upload an image and change my desktop background, most probably, remotely?

Please help, I don't like the idea of them being able to control my Mac.

Edit: Is there anything else you need to know to be able to help me?

 

[Gav2k]

Is it a custom pic or is it one of the pre installed backgrounds as you can set you mac to randomly chose and change the background.

 

[benwiggy]

The chances are very slim that this is because of some external interference.

How do you know that your colleagues are doing this? Are you sure that they do not have physical access to the machine? Have you turned on password to wake after the screensaver is active?

Is this a work computer? Perhaps you should take up the matter with your manager.

 

[0983275]

Disable screen sharing/vnc if you're not using it, if it's disabled then that narrows it down.

How is SSH configured?

 

[ChrisA]

None of your security precautions apply if others are allowed physical access to the computer. They can boot it from their own external disk or a CD.

Also you may have other accounts on the machine that or not passworded. Like the accounts for the web or database server. Check your /etc/passwd file.

 

[GGJstudios]

It is extremely unlikely anyone is doing this remotely.

I don't know why and how, but my background is being changed on my computer.

What is it being changed to? The default background? Is it happening after you restart? If so, this may be helpful:

Delete the following file, then restart your Mac:

/Users/yourusername/Library/Preferences/com.apple.desktop.plist​

Your Library folders are hidden by default in Lion and ML. To get to your /Library or /Users/yourusername/Library (also known as the ~/Library) folders in Lion and ML:

• Launch Finder and click Go > Go to Folder and type: /Library or ~/Library
  
• Hold the Option key while clicking the Go menu item, which reveals your ~/Library folder in the menu.

This solution has been posted in several existing threads on this topic, found by searching the forum, including these:

wallpaper changes to default after restart
MacBook Pro Retina changes wallpaper back to a apple default one at start up.
rMBP reverting to old wallpaper most times I reboot.
Possible fix for Wallpaper resets after reboot
Wallpaper changes to default after restart
Primary desktop background won't change
MacBook Pro Retina changes wallpaper back to a apple default one at start up.
rMBP Mountain Lion wallpaper resets every startup​

 

[murmeldjur]

None of your security precautions apply if others are allowed physical access to the computer. They can boot it from their own external disk or a CD.

Also you may have other accounts on the machine that or not passworded. Like the accounts for the web or database server. Check your /etc/passwd file.

But if they would have booted, I wouldn't be logged in and online on my usual account, right?

Nothing unusual in /etc/passwd

It is extremely unlikely anyone is doing this remotely.

What is it being changed to? The default background? Is it happening after you restart? If so, this may be helpful:

Delete the following file, then restart your Mac:

/Users/yourusername/Library/Preferences/com.apple.desktop.plist​

Your Library folders are hidden by default in Lion and ML. To get to your /Library or /Users/yourusername/Library (also known as the ~/Library) folders in Lion and ML:

• Launch Finder and click Go > Go to Folder and type: /Library or ~/Library
  
• Hold the Option key while clicking the Go menu item, which reveals your ~/Library folder in the menu.

This solution has been posted in several existing threads on this topic, found by searching the forum, including these: <URLS HERE>

It changes randomly at no specific time. It changes to images taken by my colleagues.

Disable screen sharing/vnc if you're not using it, if it's disabled then that narrows it down.

How is SSH configured?

Screen sharing is disabled, no idea about VNC or SSH. How can I check these things for incoming connections?

The chances are very slim that this is because of some external interference.

How do you know that your colleagues are doing this? Are you sure that they do not have physical access to the machine? Have you turned on password to wake after the screensaver is active?

Is this a work computer? Perhaps you should take up the matter with your manager.

I know, because they usually change it to an image they took on my awhile ago. They have "physical" access to the machine, but it is _always_ password protected with the screensaver. Password after wake up.

I am going to, if we aren't able to solve this. But still I want to know if they have access to it. I feels unsecure.

Is it a custom pic or is it one of the pre installed backgrounds as you can set you mac to randomly chose and change the background.

It is an image taken with an iPhone 5 camera. Every time the background is changed, the image "image.jpg" are put in /users/myusername/.

 

[GGJstudios]

They have "physical" access to the machine, but it is _always_ password protected with the screensaver. Password after wake up.

Make sure yours is the only user account enabled and change your password to something long and complex. Also, you'll need to check to see if they've installed anything, since they have physical access.

 

[benwiggy]

Don't try to solve it. Report it. It's employees abusing a work computer.