Updated in 2023.1
SFTP (Secure File Transfer Protocol) is similar to FTP (File Transfer Protocol), but with the added security of SSL encryption. As long as macOS does not support SFTP upload out-of-the-box since 2018 (i.e., starting with High Sierra), transfer over SFTP may fail with the following error: "Protocol "sftp" not supported or disabled in libcurl". To resolve this error, you need to install cURL with OpenSSL (curl-openssl) on every macOS computer you want audited. This article describes how use Homebrew to configure your macOS computers to deliver audit snapshots via SFTP.
Homebrew is a third-party package management system believed as "the missing package manager for macOS (or Linux)." See how to install cURL with OpenSSL using Homebrew.
To install the Homebrew package manager, paste the following command in the macOS Terminal:
/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
In the macOS Terminal, run the package to install curl-openssl:
brew install curl-openssl
In the macOS Terminal, run this command to add the link to PATH:
echo 'export PATH="/opt/homebrew/opt/curl/bin:$PATH"' >> ~/.zshrc
NOTE: The PATH must be for the root user, because the audit agent is run by the launch daemon, and that daemon runs under the root.