A DESCRIPTION OF THE PROBLEM :
processCreate in ProcessImpl_md.c passes a const jchar* for lpCommandLine which is obtained from GetStringChars(), perhaps without making a copy, however CreateProcessW() can modify it.

From the CreateProcessW docs:

The Unicode version of this function, CreateProcessW, can modify the contents of this string. Therefore, this parameter cannot be a pointer to read-only memory (such as a const variable or a literal string). If this parameter is a constant string, the function may cause an access violation.