BD-Video Key Extraction

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This guide is only for Dumping Keys from Blu-Ray Video discs, for dumping the discs see Disc Dumping Guide (MPF).


Desired Information

With this guide, we'll be looking to find / dump the following information for your BD-Video disc:

  • AACS MKB version number
  • Media Key
  • Volume ID
  • Volume Unique Key
  • Unit Key File Hash

A proper redump entry will display this info as under Protection in this example.

Method 1: Find VUK + DVD Fab

Unlike Method 2 (libaacs + VLC), Method 1 works on Media Key Block (MKB) versions past 68, for which it can only extract the UnitKey (UK).


Some versions of Find VUK and DVDFab don't play well together. Your experience may vary.

  • Find VUK (unzip FindVUK in a folder with write-access)
  • DVDFab (install)


  • DVDFab should be closed.
  • Insert Blu-Ray disc.
  • Launch FindVUK.exe, this will automatically launch DVDFab.
  • Select "Try" to use DVDFab as a trial.
  • A progress bar window should appear as DVDFab is processing the disc, which takes a few seconds. FindVUK should report that it found the key.
  • Eject the disc, close FindVUK, close DVDFab (you may have to forcibly kill the process, for me it frequently hangs at that time).
  • In FindVUK's OnlineDB_Backup subfolder, an xml file is created for each disc. Example for [1] - D6630E5AA891CE4164A44E627E5672F092D0D717-BDROM (Meta).xml:
<?xml version="1.0" encoding="UTF-8"?>
 <DiscId Date="2008-04-30">D6630E5AA891CE4164A44E627E5672F092D0D717</DiscId>
   <UnitKey Nr="1">562D5AC9EF5925866D7F07BBDC8ADFEF</UnitKey>
   <MetaTitle Language="" Manual="1">Metal Gear Solid 4 Bonus Disc</MetaTitle>
   <Hash Type="MD5" File="MKB_RO.inf" Size="1048576">BF8D213F679D3423526B1185B30C63D2</Hash>
 <Application>FindVUK 1.09</Application>

Method 2: libaacs + VLC

This guide works on Media Key Block (MKB) version 68 and below. For reference MKBv69 was skipped, and MKBv70 was released around 2019-07.


Check MKB version before Dumping

  • If you ever put a disc with MKBv72 or higher, the key dump method below will never work again in that drive until new processing keys are available. I don't know the technical details but it seems Blu-Ray discs are able to update keys in your drives flash memory. After putting any MKBv72 disc that drive will only be able to decrypt using proprietary software.
  • As I understand, you are allowed to put the disc into the drive, only if you playback/decrypt the disc it will update your drive keys. So checking MKB version before playback should be possible.

Dumping Guide

  1. Start Here
  2. Then create the directory "temp" at C:\ and follow the steps on the above tutorial (1. Start Here) thread under "Debugging:".
  3. Now playback any BDMV with VLC and the key will outputted to the file "c:\temp\debuglog_aacs.txt". You will be looking in this txt file for the following info:
src/libaacs/aacs.c:794: Found config entry for discid c7ff1ab7649625bf62ac2607954602749d38824a
src/libaacs/aacs.c:809: Found media key for c7ff1ab7649625bf62ac2607954602749d38824a: a227b69d67559b47a82fa79a7d1a3543
src/libaacs/aacs.c:817: Found volume id for c7ff1ab7649625bf62ac2607954602749d38824a: 48aca844b6389900f55a09c2433996f0
src/libaacs/aacs.c:824: Found volume unique key for c7ff1ab7649625bf62ac2607954602749d38824a: 28621b7f8e00d30389cdb8a2c70209a1
src/libaacs/aacs.c:828: Acquire CPS unit keys from keydb config file...
src/libaacs/aacs.c:864: Unit key 0 from keydb entry: 31c131a832ef8b3d9fbaeedac8366ff3
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