It's a batch file, which means it is basically a text file. You can view its contents in a text editor such as Windows Notepad, though you may lose paragraph formatting.
I've looked at it. There's nothing fishy in there, at least at the time I posted this.
All this little program does is to create a file, "perfc", in the Windows folder, and make the file read-only.
If you still don't want to run that batch file, you can accomplish the same thing by opening an administrator command prompt and entering the following two command lines:
echo Petya vaccination file - Do not remove. > C:\Windows\perfcJust copy and paste one line at a time into the window, then hit Enter. If you don't see an error message, the command probably worked.
attrib +R C:\Windows\perfc
If you don't know how to start an administrator command prompt, that information is easy to find in an Internet search.
Use Windows Explorer/File Explorer to verify that the new file "perfc" has been created in the Windows folder. Right click the file to verify that it is read-only.
Should be: Right click the file and select Properties to verify that it is read-only.
Thank you.