"The challenge we face is that many of these are not designed with security in mind. Many users do not realise that they are essentially deploying a tiny web-enabled server in their home that could potentially be subverted to cause harm," he told CNBC in an email.
"Cisco Talos has tracked large campaigns by spotting attackers attempting to guess logins for Internet connected devices in order to gain access and recruit them into a denial of service botnet."
The market is coming up with solutions to this problem. Earlier this week, Symantec launched the Norton Core, a home wi-fi router designed to secure and protect connected devices.
The device can scan incoming data for viruses and malware, and can quarantine connected devices if they become a threat, before alerting the user to the problem.
"We've all seen the high-profile attacks in recent months and know that hackers are now exploiting an array of connected devices as a new mean to access personal and financial information," said Fran Rosch, executive vice president of Symantec's Consumer Business Unit, in a press release.
"Norton is extending our digital safety platform in an innovative way – to now include a wireless home router with an atypical artisanal design – to help our customers incorporate security more personally and elegantly into their homes."
Devices such as the Norton Core may not be enough. Consumers need to be more safety-conscious and companies making connected devices need to prioritize security, according to Greer-King.
"While technology continues to advance to help protect our networks, we need a combined effort to help protect Internet of Things (IoT) devices, which includes users being careful that they don't use pre-set passwords on IoT devices that could be easily compromised by attackers and for manufacturers to ensure security is built in to the devices as a priority right from design phase," he said.
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