is win64 version bit a malware

[Joel-Nickson]

was trying to download matterbridge and found that all of your files are above 40 mb except the win 64 bit version which is only 800bytes ,
it seems suspicious and even the windows thinks that its a malware after download ...
same with the 32 bit version (thinks it could harm the pc)

[42wim]

That's why there is a checksum: https://github.com/42wim/matterbridge/releases/download/v1.22.0/checksums.txt
The win64-bit is also 50MB

Your download probably failed, redownload