I downloaded the latest 1.20.4 build from modrinth and now my antivirus is saying its malware

Could you upload your jar to VirusTotal and post the result here?

https://www.virustotal.com/gui/file/cafe155e902f6e2e13678624bab726cc88625d9fe603ecb9b2f9dfaefce0819e

The hashes of the jars all match up with my local build, which hopefully should not contain anything malicious. I think this might be a false-positive, although it is definitely better to be on the safe side. I am digging through the jar downloaded from Modrinth and checking whether there is something bad with it

This is the same jar that is available from CurseForge and GitHub.
Putting all of the jar-in-jar dependencies through the same scrutiny it comes out without any hits. I scanned them on my Windows laptop too using Windows Defender without any issue. It is very likely that this is a false positive.
I could not find any malicious code either digging through the compiled jar. I have not dug through the jij, although it is unlikely anything there is causing any issue

https://www.virustotal.com/gui/file/a19a46a248faae2bd2de413f15d522bd43ea7328efe0e719f9a0fa3b2b01778b
https://www.virustotal.com/gui/file/06ef4cd4120b1bad1ba4817476a5403368e4e99e0cfc592cfb17c816ea937cbd
https://www.virustotal.com/gui/file/f9f8a528e7a27216d9949d00ae39a36eb920b0400b1da90745d242cf158bcc9a
https://www.virustotal.com/gui/file/42d2f766f93072b8b218d675d21bcc34562f47c45ad6fc8582716891a8c29ee1
https://www.virustotal.com/gui/file/3e2b921664d91ef819d332d2a6af17bd0d6dbf71fd7d8fe86643ca38cea02fcb
https://www.virustotal.com/gui/file/cafe155e902f6e2e13678624bab726cc88625d9fe603ecb9b2f9dfaefce0819e

Ok thanks i thought it mighta been a false postive