As I understood it, your question is if somebody could patent your invention in a non-US country after you showed it to them.
I'll assume your non provisional is validly filed but not yet published.
There are two risks.
One, improvements. Everyone knowing about your invention can file patent applications for improvements. If there is no NDA or similar provision, that's completly legal. For places like Europe, your patent application will count as prior art for non-obviousness/inventiveness only if the other application is filed after your application. In theory, if there is no NDA etc., you telling other people could count as a publication, but proving that and the exact content etc. ... So that's one risk.
The other one, somebody else filing the same (your) invention elswhere. Art. 54 EPC (Europe) as an example provides that a patent application may not be granted if the same invention has been published or the content of an ep patent application or a PCT designating EP effectively from the filing date.
So your unpublished US aplication is not prior art for an EP application! If you file a PCT (designating EP) or EP application with valid priority to the US application, you can heal that. (Which is only possibl up to 12 months after the first application, so if your application claimed pirority of a provisional, 12 months after the filing date of the provisional!)
That means, if you tell someone about your invention, they could file it somewhere else. That would be illegal, but it would be up to you to prove they stole it. Or at least that you publicly disclosed it, which would count as prior art.
To summ it up:
if you have the money and will and can still validly claim priority to the first application (yes, ppas count) to file a PCT and it the priority holds because the first filing was well written -> improvement filings, but those can come after the normal publicaion anyways.
If any of those answers no -> there is a risk.