A security notice email was sent Thursday, although it seems the breach occurred between June 2, 2018 and March 23, 2019 as well as between April 21, 2019 and April 22, 2019.
Flipboard says that as soon as it discovered the unauthorized access on April 23, it launched an investigation, assisted by an external security company.
Flipboard, a platform that aggregates digital content and allows users to create their own magazine-like packages, has not said how many users were affected. It has 150 million users.
The company says it has not seen unauthorized access to third-party accounts -- users can connect platforms like Facebook to their Flipboard accounts.
The incident did not involve Social Security numbers or other government-issued IDs, bank account, credit card or other financial information, as Flipboard says it does not collect this information from its users.Users can continue to use their Flipboard accounts, but will be prompted to update their passwords at their next login.
Some users will also be prompted to reconnect to third-party services previously linked to Flipboard.