Reverse Engineering (Decompiling) software that you own to fix errors and allow interoperability is explicitly allowed.
For example article 6, part 2 (a) does not allow the information retrieved to be used for any purpose other than establishing interoperability. The hackers stepped over that line when they released some of what they discovered for the purpose of publicly criticizing the manufacturer.
I fear that (allowing for the "someone with enough money and lawyers can make your life hell" effect) you are not.
It is either that or DRM means the OEM gets to remotely shut down entire train network whenever they like? Imagine the money one could make with such a service.
That's bonkers. And criminal.
Neither cares about breaking DRM or IP, but third party (including vendor) manipulation.
This isn't DRM (though that's bad too). It's far worse. It's ransomware, they hijacked trains. Everyone involved should be locked in a dungeon for the better part of a century.
Newag's revenue is about $300 million. This isn't Siemens.
https://www.traple.pl/legalna-dekompilacja-programu-komputer...
The article is in polish, but auto-translate should do it's job easily.
If the law is huge and complex, and a large company wants to make your life hell...