Cant update/install homebrew packages with Kaspersky Security Software (Self Signed Cert)

I presume your company is using Kaspersky Endpoint Security.
I would suggest asking your IT admins to add brew update sources to trusted web addresses.
Or perhaps you could ask them for privileges to edit Web Monitor exclusions in your KES client app and add brew to trusted websites yourself, here is an article from the online help: https://support.kaspersky.com/KESMac/11.1_adminguide/en-US/96925.htm

I would also recommend your IT admins to get in touch with Kaspersky Support to resolve this issue.