Windows Firewall allows connection from any IP regardless of rule that only allow a specific IP

Posted by Pierre-Alain Vigeant on Server Fault See other posts from Server Fault or by Pierre-Alain Vigeant
Published on 2012-09-25T21:07:38Z Indexed on 2012/09/25 21:39 UTC
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I have configured the Windows Firewall to Block (default) incoming connection on the public profile.

Windows Firewall Public profile shows incoming connection as blocked

I have created a rule for a port (in this case, this is Sql Server) that explicitly states that only my office static IP is allowed.

SqlPort 1433 is allowed for my IP only

If I test from my office, I am able to connect to the port. I was expecting that anybody outside the office would not be able to connect, but this is not the case. I asked a friend to telnet the port to see if it would reply and it does even if he's not on my network.

I am a bit confuse here. Shouldn't it block everybody but the given IP? Is my server completely unsecured?

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