It's just an alternative to BTC tool, it's a very basic tool that does the job for those who can't afford something like Awesomeminer, you are probably using Bitmain's firmware so why worry about getting hacked using their tool? I had no problem using those tools back in the day before buying proper monitoring software.

Keep in mind that most antivirus programs will flag tools like this, most of the time those are false positives that you can ignore.

Actually, the tool has its own Antivirus you can scan a batch of your miners and if it detects one of the infected miners it shows poisoned under status.
Much better learn and read their PDF guide from this link below to learn how to use it and its official tool provided by Bitmain.

- Apminer tool and user guide

Its as safe as the person using it. There is nothing inherently unsafe about the program itself, but I wouldn't rule out people ability to screw things up.