I don't believe the "Digital Video Express"[1] (aka DIVX[2]) discs were ever cracked while they were on the market. But that's only because they were only sold for 1 year and nobody bought any. Even now finding information about the disc format is rare. Although anyone who has a reason to try probably should be able to do it easily since it was just 3DES.

[1] https://en.wikipedia.org/wiki/DIVX

[2] And this is when I remember that Wikipedia links are case-sensitive