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timhhyesterday at 3:53 PM1 replyview on HN

> Yes, for local password authentication.

It's really really not. By default PAM has a difficult-to-disable 2ish second minimum delay for all authentication methods. However this is completely pointless for local password authentication because PAM checks password using unix_chkpwd, which has no delay. The comment I linked to is explaining that unix_chkpwd has a silly security theatre delay if you try to run it in a tty, but that's trivial to avoid.

If you want to brute force local password authentication you can just run unix_chkpwd as fast as you like. You don't need to involve PAM at all, so its 2 seconds delay achieves nothing.

It maybe does more for remote connections but I'm not sure about that either - if you want to check 10k ssh passwords per second what stops you making 10k separate connections every second? I don't think the 2 second delay helps there at all.

> Change both the config files and you can remove the delay if you want.

This is extremely complicated. See the comments in the issue for details.


Replies

onraglanroadyesterday at 7:23 PM

No, it's very simple. Do what I said in my comment. Add nodelay to the options for pam_unix.so and set pam_faildelay.so delay=0

That's it. You didn't link to any issue and the weird mistakes and justifications you're making feels like arguing with an LLM.

You obviously can't run unix_chkpwd against a local account without root.

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