That is a 'your PC issue', most certainly.

No game would be shipped or survived a single day on the forums, if this were an actual (years old) bug. Everybody would have it. 100.000+ people would complain.

Update your drivers? Check your PC? Cap your framerate.

So-called 'memory leaks' are possible - and even more common than not - but not with decades old games, everybody played for years?

Hello, as said the game as being played a lot but if you played normally it's probably more an issue on your side than a very rare bug.
You can also eventually check in the Even Viewer, tab Windows Logs then System. If your system had the time to log the issue you should find some red icon when looking around the time you had this issue, click on it and on the general text field in the bottom you can get some verbose of the log. Often it isn't clear but maybe it can give you already a hint at what happend
If it still happen and you have some very high CPU maybe you can limit the number of cores the game has access