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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.
Distribution: Debian, Red Hat, Slackware, Fedora, Ubuntu
Posts: 13,602
Rep:
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.
Distribution: Debian, Red Hat, Slackware, Fedora, Ubuntu
Posts: 13,602
Rep:
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.
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
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