It has been brought up in the past that package managers such as
pip are vulnerable to man in the middle attacks (see https://www.reddit.com/r/Python/comments/17rfh7/warning_dont_use_pip_in_an_untrusted_network_a/). This is due to all packages being downloaded through HTTP rather than HTTPS. To the best of my knowledge I do not believe shasums of the packages are verified as well.
I was curious if Homebrew packages and casks are vulnerable to MITM attacks? I know that shasums of packages are verified once downloaded. This indicates that if a man in the middle attack were to occur, it might be possible to detect this. Does Homebrew verify SSL cerificates and use an HTTPS connection?
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It should be specified that the primary concern of MITM attacks is on public networks.