Because it is a .7z (7-Zip) file, it is a compressed archive. You cannot know the "full post" or content without extracting it, but these files generally fall into three categories:
Try converting the string from Cyrillic (Windows-1251) back to UTF-8. It may reveal a legible name in a different language (like German or Chinese). ü$&$l§0§ý.7z
Do you have the or the context of where this filename was found so I can help decode the specific origin? Because it is a