How Were DVDs Cracked?

[BestPCBuilder2017]

So first off, if this is against, the rules, feel free to delete the post and what not, but I did some basic searching and haven't really found much. I was told that DVDs were cracked almost instantly by some high school student, but I haven't really heard how they were cracked or what the flaw was exactly. I'm just curious as to what it is/how it was done. You obviously don't have to go into too much detail, but it would be helpful to understand for historical purposes. I'm interested in how it lead to the development of Blu-rays over the previous generations material. 

 

(my bad wrong section) >.>

[PlayStation 2]

To make a long story short, CSS was a pretty shitty encryption system and people were able to grab the key for it on early DVD players. That's from what I remember, so it might not be accurate.

[Dzzope]

erm, Blu-rays were designed for additional storage not for security or strength of the media (depending on what you mean by cracked)

 

You need to be much more specific with what your asking about.

 

If it's security against ripping the media, that is a whole different topic to DVD vs blu-ray as there are more than a few different kinds of protection used especially when talking about different types of content.

[mariushm]

See https://en.wikipedia.org/wiki/AACS_encryption_key_controversy

 

In simple words, DVDs had a protection mechanism based on encryption. This encryption technique has a master key, a 16 character/byte "password" and from this master key, "smaller" keys can be generated and these smaller keys can be invalidated (disabled) at a later time.

In order to legally decrypt the content from the DVD, you needed one of those smaller keys and you had to pay a fee to the people who made the encryption and promise to agree to some security rules (on order to protect this key) and in exchange they gave you one of these keys. You could then use this key to decrypt content.

If they somehow found out you didn't protect that key properly, all the retail discs produced after that date would have your key in a blacklist file on the disc, so your product would no longer be able to decrypt the content.

 

One of the first people to break the encryption has simply installed a DVD player software on his computer (I think it was WinDVD) and saved the contents of the RAM to hard disk while playing a DVD, or something like that, and found out that perhaps due to a bug in the software or maybe laziness from a programmer's part, that 16 character key was still present in computer memory while the disc was playing (normally it shouldn't be).

So the guy wrote a software pretending to be that software player and using that software's key to decrypt the contents fo the DVD.  The organization handling the keys blacklisted that key so the software could only decrypt DVDs produced before that time, but it was a good start.

Eventually, programmers figured out that master 16 character key from which all smaller keys are produced, so any decrypting software could generate new unused keys and pretend it's a new software player or hardware dvd player and they could do nothing about, the software can impersonate any other software or hardware box.

The company owning the encryption system changed that master key several times but all those keys  have leaked.

 

 

[BestPCBuilder2017]

On 4/27/2017 at 6:24 AM, mariushm said:

Eventually, programmers figured out that master 16 character key from which all smaller keys are produced, so any decrypting software could generate new unused keys and pretend it's a new software player or hardware dvd player and they could do nothing about, the software can impersonate any other software or hardware box.

The company owning the encryption system changed that master key several times but all those keys  have leaked.

Why would there be a master 16 character key above the smaller keys? How did they find out about the master key?