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On Wednesday 03 December 2008 22:02:43 Steve wrote: |
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> I've recently discovered a curious pattern emerging in my system log |
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> with failed login attempts via ssh. |
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> |
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> Previously, I noticed dictionary attacks launched - which were easy to |
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> detect... and I've a process to block the IP address of any host that |
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> repeatedly fails to authenticate. |
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> |
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> What I see now is quite different... I'm seeing a dictionary attack |
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> originating from a wide range of IP addresses - testing user-names in |
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> sequence... it has been in progress since 22nd November 2008 and has |
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> tried 7195 user names in alphabetical order from 521 distinct hosts - |
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> with no successive two attempts from the same host. |
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Slashdot yesterday, read the front page |
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It seems to be a co-ordinated and very well synchronized stealth bot-net. You |
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are one of many that has noticed this. I am noticing scans on machines that |
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have never been scanned before in all the time they have been up. |
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You should indeed be very concerned and take extra special due care with your |
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security arrangements currently. In fact, if you admin machines that are in |
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any way critical, you really *really* should be undertaking a thorough |
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security audit and make very sure you have done everything and covered all |
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your bases. |
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-- |
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alan dot mckinnon at gmail dot com |
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