A Hungarian man has pleaded guilty to extortion and transmission of malicious code after hacking into the IT systems of global hotel chain Mariott International.

Attila Nemeth, who pleaded guilty in a US court yesterday, contacted the company’s Washington hotel in November last year, saying that he had been accessing the hotel’s computers for months and had taken proprietary information. He threatened to reveal this information unless Mariott gave him a job maintaining their IT systems.

Marriott contacted the US Secret Service, which created a false employee identity in order to communicate with Nemeth. The US Secret Service invited Nemeth to fly to Washington for an interview, and he emailed a copy of his passport for the flights.

On arrival in Washington, he was met by a secret service agent posing as a Mariott employee. During the interview, Nemeth demonstrated his access to the Mariott system and confirmed that he had accessed the systems and stolen confidential information. He also revealed where Mariott’s data was stored in Hungary.

Nemeth was able to access to Mariott’s systems through a malicious email attachment sent to Mariott employees, which when opened created a ‘backdoor’ through which to access its network.

He will be sentenced on February 3 next year, and faces a maximum of 15 years in prison for the transmission of malicious code and threatening to expose confidential and proprietary information.