https://www.theguardian.com/technology/2013/jul/26/scientist...
The paper has been published only in 2016, with a few amendments to "hide" (maybe) the parts that could have led to replication by thiefs:
https://www.computerworld.com/article/2971826/cybercrime-hac...
https://www.usenix.org/conference/usenixsecurity15/technical...
Please note how the Authors only tested a few VW models, but Porsche and a number of other luxury car manufacturers used the same chip/mechanism so that itis very likely to be hackable in a similar way.