Useful Linux Security Tools

Many programs are available which can help prevent break-ins and minimize the damage caused.  Since these programs are used to protect the security of your system, make sure you get any such tools from trusted websites.  Be careful with pre-compiled binaries, especially if you run these programs as root.

 

  • Install ssh and SSL FTP and use them instead of telnet, rlogin, rsh, and ftp to prevent unencrypted passwords from being sniffed from off the network.
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  • Install TCP Wrappers to prevent access from untrusted sites or to limit access only to specific sites.
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  • Use shadow passwords so that the system file containing the actual encrypted passwords is not accessible to others.  Redhat's default configuration does not use shadow passwords, but this can be easily changed by using the pwconv tool.
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  • Use Tripwire to be notified when system files have been modified or when possible trojan horses have been inserted into your system.