A photo of Mark Zuckerberg sitting next to his laptop has revealed the Facebook boss obstructs the computer's inbuilt webcam and microphone. The head of the FBI also does it. And experts say, we all should too.
Far from being the actions of a paranoid conspiracy theorist or something only high profile people need to worry about, covering up your webcam and microphone is "very, very sensible", according to an Australian cyber security expert who says people should be much more careful than most currently are.
Dr Mark Gregory from RMIT University says that hackers attack webcams via attachments containing malware, and anti-malware software is not fool-proof in preventing it.
"It's not just key loggers that we've got problems with now, it's essentially software that's taking control of the keyboard, microphone and cameras," Gregory tells SBS Science.
"I'm looking at my computer right now and I've got a screen over the camera, and the microphone disconnected, because there are so many different variations of malware and other software that try to get onto our computers and laptops and tablets that it's very, very difficult for the anti-malware and anti-virus companies to keep up.
"So people need to be very, very careful. On a laptop what you're really trying to do is tape over the camera, and putting a bit of tape over the microphone generally tends to muffle what the microphone will pick up," says Gregory.
"Obviously on a PC, unless you're using the camera and the microphone they generally should be disconnected, but if they're not disconnected, then at least the camera should have a cloth or something put over it so that it can't be turned on by one of the malware software going around."
Zuckerberg hasn't commented on the tape on his laptop, but FBI’s director James Comey has previously revealed: “I put a piece of tape over the camera because I saw somebody smarter than I am had a piece of tape over their camera.”
Documents leaked by former National Security Agency contractor Edward Snowden allege US and UK spy agencies intercepted webcam images from millions of Yahoo users around the world between 2008 and 2010.
And Security company Symantec has warned users not to keep computers with webcams in their bedrooms and "not to do anything in front of one that they wouldn't want the world to see".
Dr Mark Gregory says computer companies like Microsoft and Apple leave it up to users to get antivirus and malware protection software, and he believes that should change.
"This whole idea of leaving it up to third party companies to offer a combination of free and paid software is wrong in my view," he says.
"It's a real problem [that needs to be] better addressed by the industry, and that includes the device manufacturers and the people that provide the operating systems.
Until then, do as Mark Zuckerberg does. "What he's doing is very, very sensible," says Gregory.