How to check if your phone number has been leaked by Facebook data breach

Facebook users have been urged to check if their mobile phone numbers have been put at risk following a data breach.

Facebook users have been advised to check to see if their mobile phone numbers have been shared online following a data breach on the social media site.

It comes after Aldi shoppers were warned about an email scam (opens in new tab) offering £200 in vouchers.

Around half a billion Facebook users could be affected after it was revealed that the social media giant experienced a data breach but the leak of private and personal information is thought to be more serious than first thought as it contained private numbers that were previously hidden on profiles.

The huge Facebook security breach took place on Saturday, 3rd April when records for 533 million Facebook users - including numbers belonging to more than 11.5 million UK residents have been dumped online and 2.5m email addresses.

But the numbers exposed were initially believed to have been ones that users had featured on their profiles but it has since been revealed that a 'second category of info' has been breached.

Just last month households were warned of Census 2021 scams (opens in new tab) and more scams are expected as England navigates the roadmap out of lockdown (opens in new tab).

Ashkan Soltani, the former chief technologist of the US Federal Trade Commission (FTC) wrote on Twitter, 'I found two different phone numbers entries for me in the [Facebook] breach,” he wrote. “I list only one [of] those phone numbers in my 'profile'. Plenty of people use different, more sensitive numbers for account recovery purposes which they wouldn't make viewable to even friends.'

While the leak of a private number doesn't allow hackers access to accounts it can help them discover which numbers they need to copy in order to break through two-factor authentication.

One user wrote, 'If you've never changed your Facebook password, please do it now! Facebook had a data breach that affected more than half a billion users.'

Meanwhile, Jason Kint, the head of digital content Next trade association highlighted the cause for concern. He wrote, 'This is a big deal if it wasn't just the public profile phone number but the account recovery [phone number], these two are not always the same and when they're not it's also frequently for sensitive/security reasons.'

Facebook users are urged to check if their data was included in the breach by entering their email address or phone number into the Have I Been Pawned (opens in new tab) website.