The TFTP daemon must operate in secure mode which provides access only to a single directory on the host file system.

From Red Hat Enterprise Linux 6 Security Technical Implementation Guide

Associated with: CCI-000366

SV-50502r1_rule The TFTP daemon must operate in secure mode which provides access only to a single directory on the host file system.

Vulnerability discussion

Using the "-s" option causes the TFTP service to only serve files from the given directory. Serving files from an intentionally specified directory reduces the risk of sharing files which should remain private.

Check content

Verify "tftp" is configured by with the "-s" option by running the following command: grep "server_args" /etc/xinetd.d/tftp The output should indicate the "server_args" variable is configured with the "-s" flag, matching the example below: # grep "server_args" /etc/xinetd.d/tftp server_args = -s /var/lib/tftpboot If it does not, this is a finding.

Fix text

If running the "tftp" service is necessary, it should be configured to change its root directory at startup. To do so, ensure "/etc/xinetd.d/tftp" includes "-s" as a command line argument, as shown in the following example (which is also the default): server_args = -s /var/lib/tftpboot

Pro Tips

Lavender hyperlinks in small type off to the right (of CSS class id, if you view the page source) point to globally unique URIs for each document and item. Copy the link location and paste anywhere you need to talk unambiguously about these things.

You can obtain data about documents and items in other formats. Simply provide an HTTP header Accept: text/turtle or Accept: application/rdf+xml.