Picking up a lot of failed authentications for various accounts

Posted by Josh K on Server Fault See other posts from Server Fault or by Josh K
Published on 2010-05-18T00:56:40Z Indexed on 2010/05/18 1:01 UTC
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Filed under:

server-security

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hardening

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ubuntu-10.04

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authentication

My server is getting a lot of various failed authentication attempts for various accounts. The most common one (that I've seen ) or the root account.

I have since enabled Fail2Ban and ran several rootkit / malware checks to ensure I wasn't compromised. Is there anything else I should do? I only have three accounts enabled, and SSH access for only two. I have a full 48hr ban on anyone making more then six failed SSH login attempts. I do not have FTP enabled.

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