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Old 01-24-2006, 02:42 PM   #1
Registered: Sep 2002
Location: Tulsa, OK
Distribution: Slack, baby!
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receiving connections from source port 80, why?

I have been monitoring the firewall from my system,
and have noticed that occasionally I see connections
from IP's on source port 80 (note that I didn't
say that they are connecting TO port 80, they are
connecting FROM port 80).

I was just wondering if anyone knows why. Is it a
type of port scan?


Old 01-24-2006, 10:46 PM   #2
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Registered: Aug 2004
Location: Munich, Germany
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That will be a webserver sending data pack to your computer for a page you have requested. The Linux firewall is stateful which means that although it might be blocking port 80 for incoming connections it will still recognise a reply to an outgoing connection as part of the same connection and let it through. If you're not browsing the web at the time there are other things that use http to communicate sometimes - eg. MSN (Gaim), updates for your distro etc.


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