RHEL 8 Bluetooth must be disabled.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-230507	RHEL-08-040111	SV-230507r833336_rule		Medium

Description
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 RHEL 8 operating system. This requirement applies to wireless peripheral technologies (e.g., wireless mice, keyboards, displays, etc.) used with RHEL 8 systems. 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 Authorizing Official (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 RHEL 8 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.

Description

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 RHEL 8 operating system. This requirement applies to wireless peripheral technologies (e.g., wireless mice, keyboards, displays, etc.) used with RHEL 8 systems. 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 Authorizing Official (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 RHEL 8 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.

STIG	Date
Red Hat Enterprise Linux 8 Security Technical Implementation Guide	2023-09-11

Details

Check Text ( C-33176r833334_chk )
If the device or operating system does not have a Bluetooth adapter installed, this requirement is not applicable. This requirement is not applicable to mobile devices (smartphones and tablets), where the use of Bluetooth is a local AO decision. Determine if Bluetooth is disabled with the following command: $ sudo grep bluetooth /etc/modprobe.d/* /etc/modprobe.d/bluetooth.conf:install bluetooth /bin/true If the Bluetooth driver blacklist entry is missing, a Bluetooth driver is determined to be in use, and the collaborative computing device has not been authorized for use, this is a finding. Verify the operating system disables the ability to use Bluetooth with the following command: $ sudo grep -r bluetooth /etc/modprobe.d \| grep -i "blacklist" \| grep -v "^#" blacklist bluetooth If the command does not return any output or the output is not "blacklist bluetooth", and use of Bluetooth is not documented with the ISSO as an operational requirement, this is a finding.

Check Text ( C-33176r833334_chk )

If the device or operating system does not have a Bluetooth adapter installed, this requirement is not applicable.

This requirement is not applicable to mobile devices (smartphones and tablets), where the use of Bluetooth is a local AO decision.

Determine if Bluetooth is disabled with the following command:

$ sudo grep bluetooth /etc/modprobe.d/*

/etc/modprobe.d/bluetooth.conf:install bluetooth /bin/true

If the Bluetooth driver blacklist entry is missing, a Bluetooth driver is determined to be in use, and the collaborative computing device has not been authorized for use, this is a finding.

Verify the operating system disables the ability to use Bluetooth with the following command:

$ sudo grep -r bluetooth /etc/modprobe.d | grep -i "blacklist" | grep -v "^#"

blacklist bluetooth

If the command does not return any output or the output is not "blacklist bluetooth", and use of Bluetooth is not documented with the ISSO as an operational requirement, this is a finding.

Fix Text (F-33151r833335_fix)
Configure the operating system to disable the Bluetooth adapter when not in use. Build or modify the "/etc/modprobe.d/bluetooth.conf" file with the following line: install bluetooth /bin/true Disable the ability to use the Bluetooth kernel module. $ sudo vi /etc/modprobe.d/blacklist.conf Add or update the line: blacklist bluetooth Reboot the system for the settings to take effect.