Around 52.5 million users were affected by the bug, which proved to be the final nail in the coffin for the platform that never really took off in the first place.
Although Google says it has "found no evidence that any developer was aware of this bug, or abusing the API, and we found no evidence that any Profile data was misused," the shutdown of the social media platform is being accelerated as a result.
News of the massive flaw comes after Google in October admitted it had kept secret a major flaw in the platform that exposed private information, including names, email addresses, occupation, gender and age, of up to 500,000 users over a long period.
The company said it closed the leak in the system in March 2018 – but failed to disclose there had been a data leak to its customers for another six months.
Beyond data security, Google also admits that it failed to create a platform that delivered a long-term interest. "While our engineering teams have put a lot of effort and dedication into building Google+ over the years, it has not achieved broad consumer or developer adoption, and has seen limited user interaction with apps," the tech giant says in its statement.
So what about all your data saved on Google Plus?
You now have until April 2019 to download all your content and save it on a hard drive. In the next few weeks, Google says it will provide information on how to transfer data to other services.
Businesses that rely on the service for internal communication will still be able to make use of it after August 2019, however.
You can already download separate information from the so-called Circles, Communities and Stream in your Google+ account using Google's data export function, which also works for other Google products.
Google+ will join the so-called "Google graveyard" of more than 20 failed and discontinued experiments, which include its e-mail alternate Inbox and previous social media efforts like Google Buzz and Orkut. – dpa