The social network giant has been at the center of a firestorm for almost two years after it was discovered that Cambridge Analytica obtained user data for 2016 election meddling.
As The Verge pointed out, the suit gives "Facebook a chance to defend itself against charges of being lax with privacy and security, explaining how users have been victimized by hackers - not the platform itself".
The firm says anyone who wanted to take the quizzes was asked to install browser extensions, which then lifted data ranging from names and profile pictures to private lists of friends. Who is your yang?' and 'What kind of dog are you according to your zodiac sign?' according to the lawsuit.
On how these men could access user's accounts, the complaint stated that they trickily caused the victims to install browser extensions infected with malware.
Two men narrate how they 'luckily' missed Ethiopian airline that crashed
They all had one thing in common, he said, "a spirit to serve the people of the world and to make it a better place for us all". The plane's passengers and crew came from at least 35 different nations, and included almost two dozen United Nations staff.
Facebook notes that it publicly announced the compromise around October 31st, which roughly matches the date of a BBC report revealing the private message breach, quoting Facebook blaming malicious browser extensions.
"As a result of installing the malicious extensions, the app users effectively compromised their own browsers because... the malicious extensions were created to scrape information and inject unauthorized advertisements when the app users visited Facebook or other social networking sites", Facebook wrote. The quizzes used the Facebook Login feature, which allows people to consent to connections between third party apps and their profiles.
In a lawsuit filed by Facebook on Friday, Facebook has said that entrepreneurs living in Kiev have violated California and anti-hacking laws and will be prosecuted for violating Facebook's rules. Last year, the BBC questioned whether Facebook had been proactive enough in addressing the malicious plugins.
The hackers, Gleb Sluchevsky and Andrey Gorbachov, required users to download browser extensions to operate the quiz apps, which scraped data from Facebook pages and posted ads once they were loaded onto the browser. Also, the hackers claimed of having scraped data from 120 million accounts on Facebook.