"We have contacted browser-makers to ensure that known malicious extensions are no longer available to download in their stores", Guy Rose, Vice President of Product Management at Facebook, was quoted as saying.
The big picture: The latest security breach involving Facebook may not be the company's fault.
In the biggest-ever security breach after Cambridge Analytica scandal, Facebook in October admitted that hackers broke into almost 50 million users' accounts by stealing their "access tokens" or digital keys. At one point, hackers have put up an ad offering access to the data at 10 cents per account, but that ad has been taken offline.
The victims seems to primarily stem from Russian Federation and Ukraine, however affected accounts come from all over the world including the UK, US, Brazil and beyond. A further 176,000 accounts also contained personal data such as phone numbers and email addresses, though these might've been obtained without actually hacking the accounts, by scraping the information from users who chose not to make it private.
Early voting shatters records in New Mexico
And in the 2012 presidential election, 387,350 Tarrant County voters cast early ballots in person, election records show. The Illinois State Board of Elections says almost 840,000 early votes had been cast statewide as of late Wednesday.
Facebook became aware of the website hawking information from user accounts and started investigating about a month ago. However, this new stolen data appears to have been obtained through malicious browser add-ons.
Sample message topics ranged from photos of a vacation and talk about a recent Depeche Mode concert to complaints about a son-in-law and intimate chat between two lovers.
At the time of writing, Facebook has stated that it was working with both the Russian and Ukrainian authorities to take down the forum where the information is being sold.
The BBC noted that it's unlikely Facebook would've missed such a huge breach.
For thousands - and potentially millions - of Facebook users, correspondence sent in confidence via the social network's private messages platform have proven to be anything but.