"Earlier today, Wikimedia Foundation staff were conducting a security review of user-authored code on Wikipedia. During that review, we activated dormant code that was then quickly identified to be malicious. As a preventative measure, we temporarily disabled editing on Wikipedia and other Wikimedia projects while we removed the malicious code and confirmed the website was safe for user activity. The security issue behind this disruption has now been resolved.
The code was active for a 23 minute period. During that time, it changed and deleted content on Meta-Wiki – which is now being restored – but it did not cause permanent damage. We have no evidence that Wikipedia was under attack, or that personal information was breached as part of this incident. We are developing additional security measures to minimize the risk of this kind of incident happening again. Updates continue to be made available via the Foundation's public incident log."
