Opera, the browser categorized as reliable, safe and fast, has become victim of a data breach after hackers attacked the browser’s web sync service.
The attack, reported earlier this week, was quickly blocked, but the company believes users’ passwords and account information, such as login names, have been compromised.
Opera has reset the sync account passwords as a precaution and has sent emails to all users asking them to change their login credentials.
Additionally, users are also encouraged to reset any passwords to third party sites they may have synchronized with the service.
“We take your data security very seriously, and want to sincerely apologize for the inconvenience this might have caused,” the Scandinavian company said in a blog post.
Opera puts the number of active users of sync in the last month as 1.7 million. The total Opera user base however crosses 350 million.
First released in 1995, the Opera browser was sold to a group of Chinese internet firms for $600 million this July. Led by Qihoo 360, the deal included both mobile and desktop versions of the browser, Opera’s performance and privacy apps as well as all of tech licensing.