archlinux: pacman: error while loading shared libraries: libcrypto.so.1.1: cannot open shared object file: No such file or directory

Upgrade only openssl to version 3 from 1.1.1 and you receive this error. sudo doesn’t work, pacman doesn’t work, what do you do?

Well hopefully you have not deleted previously downloaded packages from /var/cache/pacman/pkg/ .
If not, read about the Arch Linux Archive and you will need a USB drive/stick/whatever with an archiso written on it. I will not go there.

You however do have a previous version, for instance /var/cache/pacman/pkg/openssl-1.1.1.q-1-x86_64.pkg.tar.zst.
Since you can’t sudo, use su - to become root.