hardening a server: disallow password-login for sudoers and log unusual ips

Posted by Fabian Zeindl on Super User See other posts from Super User or by Fabian Zeindl
Published on 2012-03-25T14:51:30Z Indexed on 2012/03/25 17:32 UTC
Read the original article Hit count: 289

Filed under:

ssh

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security

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login

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sudo

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pam

Two question regarding sudo-login into an ubuntu-system (debian tips welcome as well):

Is it possible to require sudoers on my box to only login with publickey-authentication?
Is it possible to log which ip sudoers log in from and check that for "unusual activity" or take actions? I'm thinking about temporarily removing sudo-rights if sudoers don't log in from whitelisted IPs. Or is that too risky to be exploited?

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