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Old 08-30-2000, 11:08 PM   #1
gravel
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Ok I am very new to Linux so bear with me. I went to http://grc.com and found that several ports were open. I am not running a dedicated firewall, YET, the 486 that I was going to use as an LRP machine died. I must say that I have 4 other computers set up on a network with a DSL connection using Zone Alarm and Black Ice for firewalls till I switch over to the LRP machine.
Now that I rambled enuff, my question is how can I close those ports that are saying "HACK ME, HACK ME, rm -rf" < i think that's right.

BTW
So far Linux really ROCKS
 
Old 08-30-2000, 11:13 PM   #2
jeremy
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The first thing you would want to do is comment out any unnecessary services in /etc/inetd.conf. What ports are you showing as open?
 
Old 08-31-2000, 05:06 PM   #3
gravel
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The open ports that grc.com reports is 25 and 113, however, I haven't run a portscanner on it yet
 
Old 08-31-2000, 06:31 PM   #4
jeremy
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Port 25 is SMTP and port 113 is ident. Neither of those ports really scream hack me. If you don't need sendmail you may want to turn it off. After you run a portscanner let us know what ports are open.
 
Old 09-02-2000, 08:20 PM   #5
gravel
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ok I finaly got to run nmap and here are the results:

25
113
515
6000
are all open. I would like to close them at least till I get my LRP box set up. Any ideas?
 
Old 09-02-2000, 09:42 PM   #6
jeremy
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Port 25 is SMTP. To close it you need to stop sendmail. On Red Hat 6.2 (which I think you are running) it would be "/etc/rc.d/init.d/sendmail stop".
Port 113 is ident. To close it "/etc/rc.d/init.d/ident stop". Some programs, such as IRC clients, may not work properly without ident.
Port 515 is for printing. You are most likely running lpr, so "/etc/rc.d/init.d/lpr stop" should take care of it.
Port 6000 is used by X. If you start X with "startx -- -nolisten tcp" it will not open the port.

NOTE: The first 3 services most likely start at boot. You will need to take them out of the startup scripts to prevent the ports from automatically being opened after the next reboot.
 
Old 09-03-2000, 12:35 AM   #7
neptuna
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Open Ports

Hey
Just joined this site.

Just a quick question: What nmap commands did you run against your box? If you are running a firewall, you should run some of the stealth and UDP scans (in case you are running NFS, YP, or TFTP). Should also run a no ping scan (for F/W or router blocking echo requests).
I thought I had everything sealed off until I ran these:
nmap -sS -sU -P0 host
nmap -sF -P0 host

Thanks
Jim
 
Old 09-04-2000, 02:55 AM   #8
gravel
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I ran nmap with those parameters and still those ports are the only ones listed
 
  


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