The implementation was sloppy. While the bus encryption was tighter, the underlying Volume Unique Keys were often still stored in memory unprotected. Once a few "leaked" keys for major studio releases hit the internet, MakeMKV could use LibreDrive to grab the MKB and cross-reference it with known keys.
To make matters worse, many discs also use BD+. This is a virtual machine that runs on your player. The movie file is encrypted, but the decryption code is contained on the disc. The player downloads a "BD+ VM" that literally rewrites the decryption logic on the fly to prevent dumping. makemkv aacs
Because MakeMKV occupies a legal no-man’s land, you cannot find it on the Apple App Store or the Microsoft Store. You download it from a single forum-run website. The implementation was sloppy
The Cat-and-Mouse of Digital Preservation: A Deep Dive into MakeMKV, AACS, and the Hostile Decryption Landscape To make matters worse, many discs also use BD+
But every time you hit "Backup" and watch the progress bar climb, remember: You are watching a war in real-time. The drive is lying to the disc. The software is lying to the drive. And in the middle of it all, a tiny piece of code is ensuring that your right to own culture survives the age of streaming.