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I blocked related port number but kerio still fails to forbid ultrasurf. Is there anyone solved this problem ?

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3 Answers 3

have a look at the last pages

They say that they blocked it.

(I hope that linking to other sites it's not a violation :p)

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Blocking of port 9666 will not help - this is localhost port only. You have to monitor connections to port 443. There is Brazilian Linux script for blacklisting ultrasurf servers using iptstate (can't find it at the moment) - but in my case it was enough just to block packets to destination network with destination port 443.

Here is another way to block -

Article from Symantec is on using hash to prevent ultrasurf application from running.

Another article on blocking based on object footprint.

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Check out Palo Alto firewalls, they inspect the payload, not the header of packets to determine application and filter on that. I like how they pull in the need for separate devices into your edge.

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