On Friday, Facebook announced that as many as 50 million users may have had their accounts compromised. For Facebook, this is a huge blow — and the latest of several high-profile breaches that have cast renewed doubts on data privacy. This highlights the need for a robust public-private partnership when it comes to cybersecurity.

Facebook said that it discovered the issue on Tuesday and that it has already been referred to the FBI for a full investigation. The company also says that it fixed the vulnerability and that the “View As” feature, which enabled malicious account access, has been disabled.