On Friday, Opera, the Norwegian company responsible for the popular browser, warned users that the Opera Sync service might have been compromised. In response, the company issued a forced password reset for all Sync users.
Opera sent the emails to Sync user base after they detected "signs of an attack where access was gained to the Opera sync system," the company said.
"This attack was quickly blocked. Our investigations are ongoing, but we believe some data, including some of our sync users’ passwords and account information, such as login names, may have been compromised."