Hardening macOS

Hardening macOS
blog.bejarano.io

To give specific examples, it is totally unclear why the article recommends creating an unprivileged account (the default user account is already unprivileged without entering a password for anything and it is unclear how e.g. su admin -> sudo command is any more secure than sudo command). If someone has local access to the machine and the admin password, you're toast whether you are logged in as admin or as an unprivileged user. Is the risk malicious processes? Maybe there is some specific authentication procedure somewhere in MacOS where defaulting to an unprivileged user makes sense, but the site does not describe one.

Another example: The article recommends going into Gatekeeper and making it less secure. The default option, I believe, is to only allow App Store programs to launch without complaining. So "only App Store and code signed apps" is actually the more convenient, LESS secure option. I do it immediately because I don't want to be stuck with the App Store, which is useless. But turning off a security feature for convenience isn't hardening.

Later; on second boot, turn off apps that want access to Camera/Microphone/Full Disk. This seems straightforward enough and worth doing, except the first step in this list was to format your computer and if you've been following the steps thusfar, no apps have access to Camera, Microphone, or Full Disk. If I remember correctly, after installing new applications, they need to do a system API prompt to gain access to those things.

And then the back half is mostly about replacing Google stuff with privacy-focused alternatives. Privacy and security aren't diametrically opposed, but they aren't the same thing either. Also, despite arguing to opt-out of Google things, the earlier "change your DNS" tip recommends using Google DNS. Also, while I use a VPN for certain use cases, recommending installing a commercial VPN places an enormous amount of trust in the VPN provider -- it's true that they probably have more incentive than Google to respect your privacy from a logging perspective, but from a security point of view, it would seem it would be way easier to compromise a small VPN provider and try to MITM some of their connections without detection than to do the same to a commercial ISP.

So overall I think the article could use a title change to reflect that much of the advice is not MacOS-specific; fleshing out to make clear how some of the changes actually prevent against security threats; and more thought given to whether this is an article about privacy, security, or both, and thus whether readers should be given information about cases when the two might be at odds with each other.

(You may have very good answers to all of these things, but adding them to the article would be more useful than replying with them here)

2: Modifying system level settings, even with an admin account, requires re-authentication. Mac OS prompts for passwords more often than Vista-era UAC prompted for a go/nogo. What's the purpose of the second user account? An "admin" account os Mac OS is not equivalent to root.

6: Strictly lowers your security since it means now native apps outside the store can run. Store apps have the highest requirements for sandboxing and other system level protections. This might be a usability step, but it has no place in a "hardening" article.

9-10: Redundant - you'll be asked if you want to enable reporting and location services on first boot.

11: You are never supposed to use different DNS providers between your primary and secondary, this can lead to hard-to-troubleshoot intermittent errors. Given the lack of recommending Chrome over Firefox, and the anti-Google stuff in the second step 4, and given Firefox's poor security history, it is strange that they recommend using Google DNS servers. Either way - use 1.0.0.1/1.1.1.1 or 8.8.8.8/8.8.4.4, don't mix them.

13: Spotlight indexes belong to the user. There is literally no security gained by "blacklisting sensitive directories", as if your account is compromised, both your spotlight index and those 'sensitive directories' are.

17: What security is gained by denying the ability of the OS to ask me if I trust a specific cert or not?

Two of the recommendations have the potential to make your Mac less secure:

1. > …install an ad blocker (I recommend uBlock Origin)

While uBlock Origin has a great track record, it requires these permissions:

* Access your data for all websites

* Read and modify privacy settings

* Access browser tabs

* Access browser activity during navigation

That is a lot of exposure, especially if a bad actor managed to take over the extension, e.g.,

In August 2017, the very popular and widely recommended Web Developer extension for Chrome was hijacked. The developer fell for a phishing attack, and the attacker uploaded a new version of the extension that inserted more advertisements into web pages. Over a million people who trusted the developer of this popular extension ended up getting the infected extension. As this is an extension for web developers, the attack could have been a lot worse—it doesn’t appear that the infected extension functioned as a keylogger, for example. https://www.howtogeek.com/188346/why-browser-extensions-can-...

2. > Consider tunneling your traffic through a VPN when connected to untrusted networks (I recommend rolling your own VPN server, or else I really like Mullvad, see ThatOnePrivacyGuy’s VPN comparison)

Again, Mullvad appears to be one of the best VPN services, but connecting to third party VPNs creates new risks and may not provide the security you expected:

Don't use VPN services. https://gist.github.com/joepie91/5a9909939e6ce7d09e29 https://news.ycombinator.com/item?id=16371030