To have nmap work locally again for security / port scans on your macOS Catalina with homebrew running openssl v. 1.1.x and avoid

dyld: Library not loaded: /usr/local/opt/openssl/lib/libssl.1.0.0.dylib

or that image cannot be found due to .. not being able to locate the library openssl 1.0.x

dyld: Library not loaded: /usr/local/opt/openssl/lib/libssl.1.0.0.dylib
Referenced from: /usr/local/bin/nmap
Reason: image not foun

do a

brew install rbenv/tap/openssl@1.0
ln -sfn /usr/local/Cellar/openssl@1.0/1.0.2t /usr/local/opt/openssl

Afterwards you can run nmap again like here below with adding results to a file:

nmap -v -sV -oA test site.com

and other tools that depend on it like Brutespray can then also be used again.

props Kungfu Lucky 7 https://github.com/kelaberetiv/TagUI/issues/86#issuecomment-690349972