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1.6.2 Ensure local login warning banner is configured properly

Information

The contents of the /etc/issue file are displayed to users prior to login for local terminals.

Unix-based systems typically display information about the OS release and patch level upon logging in. This information can be useful to developers who are developing software for a particular OS platform. FreeBSD does not use the issue file by default. sshd needs to be configured properly to utilize the /etc/issue file.

Warning messages inform users who are attempting to login to the system of their legal status regarding the system and must include the name of the organization that owns the system and any monitoring policies that are in place. Displaying OS and patch level information in login banners also has the side effect of providing detailed system information to attackers attempting to target specific system exploits. Once logged in, authorized users can easily get this information by running the " uname -a " command.

Solution

Edit the /etc/issue file with the appropriate contents according to your site policy, remove any references to the OS platform

Example:

# echo "Authorized users only. All activity may be monitored and reported." > /etc/issue

See Also

https://workbench.cisecurity.org/benchmarks/19044

Item Details

Category: CONFIGURATION MANAGEMENT

References: 800-53|CM-1, 800-53|CM-3, 800-53|CM-6

Plugin: Unix

Control ID: b5bcf4662285d84e954e1d6b891daf8a02afe69fd7c4e629b90e00ab711cb924