More than 300,000 Australians may have been caught in Facebook's Cambridge Analytica breach

Facebook has made some bombshell admissions on user data security, chiefly that “most” of its two billion users may have had their personal data skimmed from the site by “malicious actors”, and that the number of people who information ended up with Cambridge Analytica appears much higher than previously thought.

Up to 87 million users may have been affected by the leak of personal information to the political advisory firm with links to Donald Trump’s campaign machine, Facebook’s Chief Technology Officer Mike Schroepfer said in a blog post.

Schroepfer’s post contained a country-by-country breakdown of the users affected, showing it estimates 311,000 Australians had their data “improperly shared” with Cambridge Analytica.

Facebook

These hundreds of thousands of Australians could be getting an unnerving update from Facebook in the coming weeks, with Schroepfer saying it will “tell people if their information may have been improperly shared with Cambridge Analytica”.

Cambridge Analytica used the data to build profiles of voters. The data was used to target people with messages during the 2016 US presidential election campaign.

The political advisory company was recently revealed to have a registered office in Australia under the name of a car salesman. The company is not believed to have operated in the Australian market.

Schroepfer’s post also described changes the company is making to its service to better protect users’ pbersonal data.

“We believe these changes will better protect people’s information while still enabling developers to create useful experiences,” he said. “We know we have more work to do – and we’ll keep you updated as we make more changes”.

CEO Mark Zuckerberg spoke to journalists on a conference call Thursday morning (AEST), saying he still believes he is the best person to lead the company.

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