Each set of data was stored in an Amazon S3 bucket, which allows public download of files, UpGuard said.
“These two situations speak to the inherent problem of mass information collection: the data doesn’t naturally go away, and a derelict storage location may or may not be given the attention it requires,” UpGuard said in a statement.
A Facebook spokesperson released the following statement on the matter to CNN Business:
“Facebook's policies prohibit storing Facebook information in a public database. Once alerted to the issue, we worked with Amazon to take down the databases. We are committed to working with the developers on our platform to protect people's data."