One day, I found my web server is broken. It seemed that my blog lost all of its configurations such as category, tags, and so on. I accessed to the server via ssh, and found that its disk is full of mail error logs.
Jan 29 09:02:02 main sm-mta: v0T021Sx027976: SYSERR(root): Cannot exec /usr/sbin/sensible-mda: No such file or directory
I also could see that five sendmail processes are consuming 100% CPU.
I suspected that my server is hacked by spammers; however, it was not. It was due to a bug of
crontab. 1)[SOLVED] hacked by spammer? (sendmail-mta running wild)
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