Mashable: A bug in the system allowed someone who wasn't part of the user's Twitter Circle to view a tweet he had only intended for his own circle.

Twitter has finally admitted that some users' semi-private tweets were made public due to a bug that has since been fixed. Users who were affected were contacted by email on Friday, May 5—weeks after the event was first reported.

The email, which was obtained by Fortune, suggests that the security breach occurred in April 2023 and may have resulted in others outside of a user's Twitter Circle being able to view tweets that the user intended to keep private. Twitter Circle is a select group of users that a user can choose to share tweets with that aren't meant for public consumption. Twitter Circles are user-generated and curated lists of followers.

Twitter's security team found and patched the problem, but it's not clear how many users were impacted. A bug in the system allowed someone who wasn't part of the user's Twitter Circle to view a tweet he had only intended for his own circle.

In an email to affected users, Twitter provided reassurance that the platform is dedicated to safeguarding user privacy and that the issue had been resolved by the security team. The company expressed regret for the incident and acknowledged the potential risks such an event could introduce.

This event is the latest in a long line of occurrences that have called into doubt Twitter's capacity to keep users' information secure and private. The corporation has been making modifications to its platform in response to these worries. These enhancements are meant to better protect users' personal information.