An employee leaked passwords and other data from a company database and stole corporate information in an attempt to break into a corporate database.
The incident was revealed by the security firm Trend Micro, which said the data was used to access the company’s network.
Trend Micro said the information was stolen from a database used by a private security firm to protect the financial interests of RSI, the maker of the popular massively multiplayer online game EVE Online.
The leaked data included names, email addresses, email passwords, social security numbers and company emails.
“This is an extremely significant and serious breach of corporate data, as it exposes a vast amount of corporate information to the world,” the company said in a statement.
“This breach is a direct result of the breaches that occurred earlier this year, including those at Anthem, where data breaches were exposed that impacted tens of millions of users.”
The breach at Anthem revealed personal data about about tens of thousands of Anthem customers and Anthem employees was released to third parties.
The company said it was “committed to protecting the security of all of our customers and has implemented comprehensive data security measures to ensure our systems are secure”.
“Trend Micro is a world leader in cyber security and has been a trusted partner of RSPH in the past,” it said.
“We are working with our partners to resolve this matter quickly, and we are committed to continuing to work closely with Trend Micro to protect our customers.”
The leak follows a series of recent breaches of organisations across the industry.
Last week, security firm Secureworks revealed it had accessed a database of personal information of more than 6,000 workers at the software firm Red Hat.
The data, which included details of employees’ personal email addresses and passwords, was released by a cybercriminal.
It was unclear whether the breach had been carried out by Red Hat, which has not publicly acknowledged the breach.
The breach was later blamed on the theft of a private database used to store the data.
In June, the security software vendor Sophos disclosed a major breach at Microsoft that exposed a database containing personal information for more than 2 million customers and employees.
In March, the UK’s National Crime Agency confirmed that the cybercriminal behind a series the attacks, a US-based group called Shadowserver, had breached the private email of more then a million UK citizens.
The NCA said that the data breach was the largest of its kind in the country.