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Old 02-25-2008, 09:45 AM   #1
mrlinux2000
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appach attack


when i look at squid log i see that following :

217.147.30.32 TCP_DENIED/403 1372 POST http://registrace.atlas.cz/verify.aspx - NONE/- text/htm

is this an attack and if it is how to prevent it ??

i have fedora core 3 and using squid as proxy and i have lcoal client and using nat
 
Old 02-25-2008, 10:40 AM   #2
win32sux
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Quote:
Originally Posted by mrlinux2000 View Post
when i look at squid log i see that following :

217.147.30.32 TCP_DENIED/403 1372 POST http://registrace.atlas.cz/verify.aspx - NONE/- text/htm

is this an attack and if it is how to prevent it ??

i have fedora core 3 and using squid as proxy and i have lcoal client and using nat
This usually means that the IP tried to use your proxy and one of the ACLs prevented it from doing so. If all you have is local clients then my concern would be why your firewall is letting external clients connect to Squid in the first place. Even if you don't know how to firewall Squid from the outside, you should at the very least make Squid listen only on the internal interface.

Last edited by win32sux; 02-25-2008 at 10:43 AM.
 
Old 02-26-2008, 04:40 AM   #3
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thank you and this guid me to ask you :
how to make Squid listen only on the internal interface ?
thankl you
 
Old 02-26-2008, 04:52 AM   #4
win32sux
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Quote:
Originally Posted by mrlinux2000 View Post
thank you and this guid me to ask you :
how to make Squid listen only on the internal interface ?
thankl you
By specifying the address of your LAN interface in your squid.conf, for example:
Code:
http_port 192.168.1.1:3128

Last edited by win32sux; 02-26-2008 at 04:53 AM.
 
Old 02-26-2008, 07:08 AM   #5
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ok, i did that and i'll see if that message will keep coming
thank you so much ...
 
Old 02-26-2008, 07:30 AM   #6
win32sux
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Quote:
Originally Posted by mrlinux2000 View Post
ok, i did that and i'll see if that message will keep coming
thank you so much ...
Cool. Make sure you reload the config after you make the change:
Code:
squid -k reconfigure
You can use netstat to make sure Squid is only listening on that address:
Code:
netstat -an --inet | grep LISTEN | grep 3128
 
Old 02-26-2008, 07:42 AM   #7
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thank you , yes it listen on port 3128 but i found another problem , which i made a file for the bad words and it include "video" when i search using google it prevent the search but if i type "VIDEO" or "Video" it works , how can that be solved
tahnk yo
 
Old 02-26-2008, 07:46 AM   #8
win32sux
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Quote:
Originally Posted by mrlinux2000 View Post
thank you , yes it listen on port 3128
Right, but the port is irrelevant in this case.

You need to make sure it's only listening on the internal address.

Quote:
but i found another problem , which i made a file for the bad words and it include "video" when i search using google it prevent the search but if i type "VIDEO" or "Video" it works , how can that be solved
That's a completely unrelated question and as such it belongs in a new thread.
 
Old 02-26-2008, 08:04 AM   #9
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thank you , but i still have the same message it came
 
Old 02-26-2008, 08:05 AM   #10
mrlinux2000
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tcp 0 0 192.168.1.96:3128 0.0.0.0:* LISTEN
 
Old 02-26-2008, 08:08 AM   #11
win32sux
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You'll need to clarify some things about your setup. Is this Squid box also doing NAT or is it a separate/dedicated box? If it is dedicated, then would we be correct in assuming that it only has one interface on it? Because that's what it's starting to sound like. If that's the case then you'll need to tell your NAT router to stop sending connections from the WAN toward your Squid.
 
Old 02-26-2008, 08:10 AM   #12
mrlinux2000
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am using NAT and i did a transparent squid server using eth0 and eth1
 
Old 02-26-2008, 08:13 AM   #13
win32sux
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Quote:
Originally Posted by mrlinux2000 View Post
am using NAT and i did a transparent squid server using eth0 and eth1
If your Squid box is also the NAT box, and Squid is only listening on the LAN side (which your netstat output seems to confirm), then I fail to understand how someone on the WAN could connect to Squid.
 
Old 02-26-2008, 08:40 AM   #14
mrlinux2000
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me too,
thank you so much for your help which is so appreciated ...
thank you
 
Old 02-26-2008, 12:10 PM   #15
win32sux
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Could the IP be getting spoofed by something on the LAN side?

If there's a Windows box, maybe run a spyware checker.

Last edited by win32sux; 02-26-2008 at 12:11 PM.
 
  


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