Apple released MacBook Pro Flash Storage Firmware Update 1.0 on Wednesday. The update, "addresses a storage firmware issue that, in rare cases, may cause data corruption." Apple recommended that all MacBook Pro (mid 2015) models be updated.
MacBook Pro (mid 2015)
Owners of the affected model can download the update through the Mac App Store, or directly from Apple's Support site. It's a 1.9MB download from Apple's site.