I'm searching for a language which gives some basic features like the most popular languages like Python, C#, JavaScript, so math operations, string manipulation, object access and transformations, serialization, but has something like isolated execution environment by default, so you cannot access OS layer directly or easily with the language.
If talking about mentioned - let's take C# - you can access OS with .NET Framework. JavaScript executed on Node - spawn function, Python - os.system or subprocess.call etc.
How about a language in which you cannot do this by default - we are not considering exploits here or other hacking approaches, just pure language, but maybe there is a special language in which it's hard to make some exploits by default.
The other option maybe there is a special platform for existing language which prevent OS access.