EERY footage captures the moment a hacker speaks directly to a homeowner through his own security camera.

Andy Gregg, from Arizona, jumps in fright when he hears the voice of a stranger barking through his Nest smart cam – but the attack was merely a warning.

The voice coming through the gadget informs Andy that it has been compromised after his password was exposed online, opening him up to a global network of vicious cyber attackers.

Nest security cameras are internet connected, and provide 24-hour livestreaming as well as a camera and microphone to allow you to speak to people at your doorstep.

But after Andy's login details were published on the web, his camera became a potential playground for anyone wanting to spy on his movements.

The hacker speaking through the real estate agent's camera assured him he had no "malicious" intentions.

He claimed to be a “white hat hacker” – also known as an ethical hacker.

Ethical hackers break into computers and other gadgets to expose flaws so they can be fixed before hackers with more devious intentions can find them.

"Please, please don't be scared or frightened," the voice told Gregg before explaining he is a researcher from the Anonymous group in Calgary, Canada.

Anonymous is an infamous vigilante 'hacktivist' group known for carrying out several cyber attacks against governments across the globe.

The man recited a password that Andy had used for multiple websites, adding: "I'm here to help you".

'We're white hats, we don't have any malicious intent,' he added. 'I just wanted to tell you so that you can change your password before someone tries to hack you and do something malicious.'

Gregg then asked if the man could see where he lived.

"I don't know where you live right now but if someone was really that dedicated, they could geolocate an IP [address]," the hacker explained.

"They could see when you're home. There's so many malicious things someone could do with this."

The hacker advised that Andy change his password and use two-factor authentication to better protect his account.

"Even if someone does get your password, they can't do what I did and login," he explained.

Andy replied: "Well damn, that's actually insane. Thank you for letting me know and I appreciate you doing it, a little bit of a wake-up call."

Nest echoed the hackers advise in a statement, urging users to activate two-factor authentication to add "another layer of account security".

"We have seen instances where Nest customers have reused passwords that were previously exposed through breaches on other websites, and made public," a spokesman said.

"None of these breaches involved Nest. We are proactively alerting affected customers to reset their passwords and set up two-factor authentication."