Firms, such as those occupying serviced offices in Cardiff, may wish to consider educating their staff or making their systems more secure against a cyber attack.
Sebastian Zabala, Panda Security's country manager for the UK and Sweden, said a company's security could be threatened if employees are allowed to access social networking sites while they are in the workplace.
He noted web portals such as Facebook could be used by people to commit fraud against a business, allowing them to find out a variety of information that can be used to implement an attack.
Mr Zabala observed employees, including those in offices to rent, should be aware that any information they give out over the internet is never private.
"In certain circumstances, you maybe shouldn't put out what you actually do and what your hobbies are, because that can be used against you," he added.
Last week, Wirtschaftswoche revealed the threat of industrial espionage had led to some German businesses blocking social networking sites in a bid to increase the security of the company.
