Last post: 1 day
Last view: 10 hours
This isn't a false positive, but it's also not malicious.
I can break down that detection for you, though:
Win64 means that it is a 64 bit binary. Packed means that the file is compressed and obfuscated - this is usually done to prevent analysis and prevent modifications to the binary. GoLang is actually the programming language that the file was written in, as we use Go for internal development at MabiPro.
Most antiviruses will flag packed files by default, because they cannot tell if they are malicious or clean since they are unable to analyze them.
Nexon's Client.exe is also packed with Themida, and there is flags on AVs related to this too.
Actually, this file was a trial of our clientside anticheat, a replacement for Nexon's NGS, however, it was disabled after less than a week, which is why it is no longer used in your updated client.
Given that it's an anticheat, it is packed to prevent hackers from analyzing and modifying it.