A cybersecurity expert has raised the possibility that the cyberattack on Sony Pictures was not the work of North Korea, but instead carried out by a disgruntled employee. The hacking attack saw five major new films leaked alongside studio and personnel information which included the salaries of staff and personal emails. North Korea has refused to deny claims that it is behind a release and a spokesperson for the country would only say 'wait and see' when asked if Pyongyang was involved in the attack on Sony just a month before its planned release of a movie about a plot to kill the reclusive state's leader, Kim Jong Un. Cars enter Sony Pictures Entertainment headquarters in Culver City, California. A cybersecurity expert has raised the possibility that the cyberattack on Sony Pictures was not the work of North Korea . A North Korean spokesperson said 'wait and see' on Monday when asked if Pyongyang was involved in the attack on Sony just a month before its planned release of The Interview, staring James Franco and Seth Rogan . North Korea routinely refers to the United States and South Korea as hostile forces. But cybersecurity expert Hemanshu Nigam told the Hollywood Reporter that he finds it hard to believe that North Korea is the perpetrator and instead thinks it is more probable that it was the actions of an  employee or ex-employee with administrative access privileges. For the studio — which has laid off hundreds of employees over the past year in an effort to contain costs — the possibility of a disgruntled employee wreaking havoc is very real. 'If terabytes of data left the Sony networks, their network detection systems would have noticed easily,' explains Nigam. 'It would also take months for a hacker to figure out the topography of the Sony networks to know where critical assets are stored and to have access to the decryption keys needed to open up the screeners that have been leaked.' Culprit? Sony is currently investigating whether someone acting on behalf of North Korean leader Kim Jong-un, possibly from China, was responsible for hacking their computer system . In addition, he says, 'Hackers don't use such things as Hushmail, Dropbox and Facebook when they want to engage in what amounts to criminal activity. Real hackers know that these sites collect access logs, IP addresses and work with law enforcement. It is possible that North Korean-sponsored hackers were working with someone on the inside. But it is more likely a ruse to shift blame, knowing the distaste the North Korean regime has for Sony Pictures.' Sony Pictures' computer system went down last Monday after the cyber attack. Before . screens went dark, they displayed a red skull and the phrase . 'Hacked By #GOP,' which reportedly stands for Guardians of . Peace. The hackers also warned they . would release 'secrets' stolen from Sony. The data released so far from the apparently leaked documents has already been damaging - it revealed all the top executives at Sony Pictures Entertainment are white and male, raising questions about control of Hollywood's film output. A spreadsheet said to show the salaries of 6,000 Sony Pictures employees, including top executives, reveals that of 17 earning $1million or more a year, just two are not white and just one is a woman. The list was leaked to a reporter at news and pop culture site Fusion. Sony workers reportedly saw a message appear on computer screens saying 'Hacked by #GOP', understood to be the initials of a group called Guardians of Peace - although some believe North Korea was involved . Kevin Roose, reporting for Fusion, who was sent a link to the data by an anonymous source, said: 'When I sorted the list by 'annual rate,' I noticed something notable: a stark homogeneity among the people earning the most. 'Based on the spreadsheet ... the employees of Sony Pictures with the highest annual rates appear to be nearly entirely white men.' Amy B. Pascal, co-chair of Sony Pictures Entertainment and chairman of SPE's Motion Picture Group, is the only woman among the top 17 most-highly paid executives. Minority of one: Co-Chairman of Sony Pictures Entertainment Amy Pascal, the only woman earning more than $1million a year at the company, and chief executive officer of Sony Entertainment Michael Lynton . She earns £3million a year, according to the spreadsheet, joint highest on the list, along with Sony Entertainment CEO Michael Lynton. Buzzfeed reviewed almost 40GB of leaked internal data and reported it included 'employee criminal background checks, salary negotiations, and doctors' letters explaining the medical rationale for leaves of absence.' It reported the files also included a script for an unreleased pilot written by Breaking Bad creator Vince Gilligan as well as 'email exchanges with employees regarding specific medical treatments they are undergoing, while one disciplinary letter details a manager's romantic relationship and business travel history with a subordinate.' It even details the leaked information includes an email about the breastfeeding diet of a senior executive. Technology news site Re/code reported that Sony and security . consultants were investigating whether someone acting on behalf . of North Korea, possibly from China, was responsible. A source familiar with the matter told Reuters on Saturday . that Sony Pictures was investigating every possibility, adding . that no link to North Korea has been uncovered. North Korea complained to the United Nations in June about . the film starring Seth Rogen and James Franco, accusing the . United States of sponsoring terrorism and committing an act of . war by allowing production of the movie. Leaked: Five of Sony's movies including the hotly anticipated remake of Annie have been illegally shared online in recent days . The Interview is due to be released on December 25 in the United States and Canada. It is a comedy about a CIA attempt to assassinate North Korean leader Kim Jong Un. The Pyongyang government denounced the film as 'undisguised sponsoring of terrorism, as well as an act of war' in a letter to U.N. Secretary-General Ban Ki-moon. 'I personally don't care if (the movie's) disrespectful to . Kim because he's evil. But that's not the intent,' Rogen posted . on Twitter on Sunday. 'North Korea has produced tons of . propaganda films that portray America's destruction.' In addition to Annie, starring Jamie Foxx, which is due to hit theaters on December 19, Brad Pitt's critically acclaimed World War Two movie, Fury, is also being openly traded and downloaded online. By Sunday morning, Fury, which is still playing in theaters, had been downloaded 1.2 million times and Annie had been downloaded 206,000 times from unique IP addresses, according to Variety. Other Sony movies being downloaded include Mr. Turner, Still Alice and To Write Love on Her Arms. Culver City, California-based Sony Pictures said in a statement yesterday that it is continuing 'to work through issues related to what was clearly a cyber attack last week. 'The company has restored a number of important services to ensure ongoing business continuity and is working closely with law enforcement officials to investigate the matter.' Along with the FBI, Sony has brought in forensic experts from the Mandiant division of FireEye, a Silicon Valley cybersecurity company, according to a source familiar with the case who did not want to be named because the companies have not yet announced the arrangement. Mandiant helps companies determine the extent of breaches and repair damages. The firm has worked on other high-profile computer breaches, including one at retailer Target last year.
The hacking attack saw five major new films leaked alongside studio and personnel secrets which included the salaries of staff and personal emails .
The leak has been extremely costly - and embarrassing - for Sony .
Studio laid off hundreds of employees over past year  to contain costs .
Cyber expert: Theorizes an employee or ex-employee with administrative access privileges is a more likely suspect .
A cybersecurity expert has raised the possibility that the cyberattack on Sony Pictures was not the work of North Korea, but instead carried out by a disgruntled employee. The hacking attack saw five major new films leaked alongside studio and personnel information which included the salaries of staff and personal emails. North Korea has refused to deny claims that it is behind a release and a spokesperson for the country would only say 'wait and see' when asked if Pyongyang was involved in the attack on Sony just a month before its planned release of a movie about a plot to kill the reclusive state's leader, Kim Jong Un. Cars enter Sony Pictures Entertainment headquarters in Culver City, California. A cybersecurity expert has raised the possibility that the cyberattack on Sony Pictures was not the work of North Korea . A North Korean spokesperson said 'wait and see' on Monday when asked if Pyongyang was involved in the attack on Sony just a month before its planned release of The Interview, staring James Franco and Seth Rogan . North Korea routinely refers to the United States and South Korea as hostile forces. But cybersecurity expert Hemanshu Nigam told the Hollywood Reporter that he finds it hard to believe that North Korea is the perpetrator and instead thinks it is more probable that it was the actions of an  employee or ex-employee with administrative access privileges. For the studio — which has laid off hundreds of employees over the past year in an effort to contain costs — the possibility of a disgruntled employee wreaking havoc is very real. 'If terabytes of data left the Sony networks, their network detection systems would have noticed easily,' explains Nigam. 'It would also take months for a hacker to figure out the topography of the Sony networks to know where critical assets are stored and to have access to the decryption keys needed to open up the screeners that have been leaked.' Culprit? Sony is currently investigating whether someone acting on behalf of North Korean leader Kim Jong-un, possibly from China, was responsible for hacking their computer system . In addition, he says, 'Hackers don't use such things as Hushmail, Dropbox and Facebook when they want to engage in what amounts to criminal activity. Real hackers know that these sites collect access logs, IP addresses and work with law enforcement. It is possible that North Korean-sponsored hackers were working with someone on the inside. But it is more likely a ruse to shift blame, knowing the distaste the North Korean regime has for Sony Pictures.' Sony Pictures' computer system went down last Monday after the cyber attack. Before . screens went dark, they displayed a red skull and the phrase . 'Hacked By #GOP,' which reportedly stands for Guardians of . Peace. The hackers also warned they . would release 'secrets' stolen from Sony. The data released so far from the apparently leaked documents has already been damaging - it revealed all the top executives at Sony Pictures Entertainment are white and male, raising questions about control of Hollywood's film output. A spreadsheet said to show the salaries of 6,000 Sony Pictures employees, including top executives, reveals that of 17 earning $1million or more a year, just two are not white and just one is a woman. The list was leaked to a reporter at news and pop culture site Fusion. Sony workers reportedly saw a message appear on computer screens saying 'Hacked by #GOP', understood to be the initials of a group called Guardians of Peace - although some believe North Korea was involved . Kevin Roose, reporting for Fusion, who was sent a link to the data by an anonymous source, said: 'When I sorted the list by 'annual rate,' I noticed something notable: a stark homogeneity among the people earning the most. 'Based on the spreadsheet ... the employees of Sony Pictures with the highest annual rates appear to be nearly entirely white men.' Amy B. Pascal, co-chair of Sony Pictures Entertainment and chairman of SPE's Motion Picture Group, is the only woman among the top 17 most-highly paid executives. Minority of one: Co-Chairman of Sony Pictures Entertainment Amy Pascal, the only woman earning more than $1million a year at the company, and chief executive officer of Sony Entertainment Michael Lynton . She earns £3million a year, according to the spreadsheet, joint highest on the list, along with Sony Entertainment CEO Michael Lynton. Buzzfeed reviewed almost 40GB of leaked internal data and reported it included 'employee criminal background checks, salary negotiations, and doctors' letters explaining the medical rationale for leaves of absence.' It reported the files also included a script for an unreleased pilot written by Breaking Bad creator Vince Gilligan as well as 'email exchanges with employees regarding specific medical treatments they are undergoing, while one disciplinary letter details a manager's romantic relationship and business travel history with a subordinate.' It even details the leaked information includes an email about the breastfeeding diet of a senior executive. Technology news site Re/code reported that Sony and security . consultants were investigating whether someone acting on behalf . of North Korea, possibly from China, was responsible. A source familiar with the matter told Reuters on Saturday . that Sony Pictures was investigating every possibility, adding . that no link to North Korea has been uncovered. North Korea complained to the United Nations in June about . the film starring Seth Rogen and James Franco, accusing the . United States of sponsoring terrorism and committing an act of . war by allowing production of the movie. Leaked: Five of Sony's movies including the hotly anticipated remake of Annie have been illegally shared online in recent days . The Interview is due to be released on December 25 in the United States and Canada. It is a comedy about a CIA attempt to assassinate North Korean leader Kim Jong Un. The Pyongyang government denounced the film as 'undisguised sponsoring of terrorism, as well as an act of war' in a letter to U.N. Secretary-General Ban Ki-moon. 'I personally don't care if (the movie's) disrespectful to . Kim because he's evil. But that's not the intent,' Rogen posted . on Twitter on Sunday. 'North Korea has produced tons of . propaganda films that portray America's destruction.' In addition to Annie, starring Jamie Foxx, which is due to hit theaters on December 19, Brad Pitt's critically acclaimed World War Two movie, Fury, is also being openly traded and downloaded online. By Sunday morning, Fury, which is still playing in theaters, had been downloaded 1.2 million times and Annie had been downloaded 206,000 times from unique IP addresses, according to Variety. Other Sony movies being downloaded include Mr. Turner, Still Alice and To Write Love on Her Arms. Culver City, California-based Sony Pictures said in a statement yesterday that it is continuing 'to work through issues related to what was clearly a cyber attack last week. 'The company has restored a number of important services to ensure ongoing business continuity and is working closely with law enforcement officials to investigate the matter.' Along with the FBI, Sony has brought in forensic experts from the Mandiant division of FireEye, a Silicon Valley cybersecurity company, according to a source familiar with the case who did not want to be named because the companies have not yet announced the arrangement. Mandiant helps companies determine the extent of breaches and repair damages. The firm has worked on other high-profile computer breaches, including one at retailer Target last year.
disgruntled employee. The hacking attack saw five major new films leaked alongside studio and of staff and personal emails. North Korea has the actions of an  employee or ex-employee with administrative access privileges. For the studio — which has laid off hundreds of employees over the past year in an effort to contain costs — the salaries of 6,000 Sony Pictures employees,