Today’s fashion for high-end electronics in luxury hotels allowed a hacker to wreak havoc in 200 suites at once in a five-star hotel in China via an aging 'internet of things' system - switching off lights, changing the TV channel, raising blinds and fiddling with the temperature, according to Sky News.

Security researcher Jesus Molina said that his hack was pulled off using an in-room iPad and the hotel's 'internet of things' system, and began simply because he was "bored".  "I thought about looking to see if a similar system controlled the door locks but got scared," says Molina, according to Wired's report.

That did not stop him from switching on and off the "Do Not Disturb" signs on hotel rooms, according to the South China Morning Post.

The Register reports that Molina’s hack was possible due to an aging home automation system - KNX/IP - which dates from the Nineties. It’s still used widely in the Far East and in some hotels in Europe. Molina’s results formed part of the Black Hat security conference in Las Vegas.

Internet of Things: Tool for thermostatic war

Molina found that the iPads - handed out in the five-star St Regis in Shenzhen - connected to one another via the hotel’s network, he was able to access other rooms and cause (mild) mayhem. The SCMP reported that a "digital butler" app allowed Molina to control electronics at will - and map out the IP addresses of each room.

Shenzhen, the SCMP reports, is considered the "Silicon Valley" of China, and plays host to wealthy tech executives. In a previous case, a Spanish hacker seized control of automated rooms in another hotel via its Internet of Things system.

"Guests make assumptions that the channel they are using to control devices in their room is secure," Molina says. But the protocol used in the St Regis is not. "The KNX/IP protocol provides no security so any hotel or public space that have deployed it on an insecure network will make it easy to exploit."

'Ever had the urge to create mayhem?'

Molina’s presentation, 'Learn How To Control Every Room At A Luxury Hotel Remotely' is not a "hack"as such - it takes advantage of an old communication system without modern protection. Earlier this year, veteran security reporter Brian Krebs reported that hotel business centers were plagued with keylogger malware.

Hacks against hotels and their wealthy clientele are not rare in China. Earlier this year, a huge amount of private information harvested via hotel Wi-Fi networks went on sale in China – including phone numbers, dates of birth and addresses from hotel guests who logged in to networks in their rooms.

"People rushed to check hotel bookings by celebrities and their family members," says Patrick Boehler, a journalist for the South China Morning Post,who worked on the story, speaking to WeLiveSecurity.

Molina's hack penetrated deeper into the hotel's Internet of Things systems - and he says the protocol is still used in well-known hotels in the West.

"Have you ever had the urge to create mayhem at a hotel? Force every hotel guest to watch your favorite TV show with you? Or wake your neighbors up (all 290 of them!) with blaring music and with their blinds up at 3 AM?" Molina asked. " I was able to create the ultimate remote control: The attacker does not even need to be at the hotel - he could be in another country."