Ubuntu 22.04 LTS must disable all wireless network adapters.

STIG ID: UBTU-22-291015  |  SRG: SRG-OS-000481-GPOS-00481 | Severity: medium |  CCI: CCI-002418

Vulnerability Discussion

Without protection of communications with wireless peripherals, confidentiality and integrity may be compromised because unprotected communications can be intercepted and either read, altered, or used to compromise the operating system.

This requirement applies to wireless peripheral technologies (e.g., wireless mice, keyboards, displays, etc.) used with an operating system. Wireless peripherals (e.g., Wi-Fi/Bluetooth/IR Keyboards, Mice, and Pointing Devices and Near Field Communications [NFC]) present a unique challenge by creating an open, unsecured port on a computer. Wireless peripherals must meet DOD requirements for wireless data transmission and be approved for use by the AO. Even though some wireless peripherals, such as mice and pointing devices, do not ordinarily carry information that need to be protected, modification of communications with these wireless peripherals may be used to compromise the operating system. Communication paths outside the physical protection of a controlled boundary are exposed to the possibility of interception and modification.

Protecting the confidentiality and integrity of communications with wireless peripherals can be accomplished by physical means (e.g., employing physical barriers to wireless radio frequencies) or by logical means (e.g., employing cryptographic techniques). If physical means of protection are employed, then logical means (cryptography) do not have to be employed, and vice versa. If the wireless peripheral is only passing telemetry data, encryption of the data may not be required.

Check

Verify that there are no wireless interfaces configured on the system by using the following command:

Note: If the system does not have any physical wireless network radios, this requirement is not applicable.

$ cat /proc/net/wireless

If any wireless interface names are listed under "Interface" and have not been documented and approved by the information system security officer (ISSO), this is a finding.

Fix

Disable all wireless network interfaces by using the following command:

$ sudo ifdown

For each interface listed, find their respective module by using the following command:

$ basename $(readlink -f /sys/class/net//device/driver)

where must be substituted by the actual interface name.

Create and/or append a custom file under "/etc/modprobe.d/" by using the following command:

$ sudo su -c "echo install /bin/false >> /etc/modprobe.d/stig.conf"

where must be substituted by the actual module name.

For each module from the system, execute the following command to remove it:

$ sudo modprobe -r