Terminal not permited <9>

[jaclaz]

@stefan4o

Is it possible to crash so fast after internet has been connected on it?

Yes, it can be a matter of seconds or minutes.
Compare with:

Device got hacked 1 min after connected to internet

Interesting case, I performed netinstall (without default config) on my device (Chateau LTE12) to latest ROS version (7.16) because I had some trouble doing it with regular upgrade procedure due to my fault (power failure while upgrade process was in progress). After netinstall is done and rebooting I connected to ROS using Winbox and changed password but I was not unable to open Terminal (Terminal - not permitted (9)) because I wanted to apply my configuration from export. This raised suspici…

See Rules #3 and #8:

The twelve Rules of Mikrotik Club

Preamble and disclaimer: The following is a set of Rules that are intended as advice useful to avoid the most common errors observed in configuration posted on this forum. It is my personal take on the matter, and in no way approved, endorsed or recommended, officially or unofficially, by Mikrotik or their partners or by anyone else. In other words you are perfectly free to ignore them, though they represent (IMHO) a sort of (good) cheat sheet/reminder for people starting to use these devices…

Netinstall can be tricky (on both Linux and Windows), there are several guides on the forum with various things that you can try, the more extreme (but reported as surely working) is making use of a VM, see:
https://tangentsoft.com/mikrotik/wiki?name=Run%20NetInstall%20in%20a%20VM
https://tangentsoft.com/mikrotik/draft1/info/e762873c845810043514a7beab67065991d919efd102032d0086ec1d8e721150