RHEL 8 must disable the asynchronous transfer mode (ATM) protocol.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-230494	RHEL-08-040021	SV-230494r942918_rule		Low

Description
It is detrimental for operating systems to provide, or install by default, functionality exceeding requirements or mission objectives. These unnecessary capabilities or services are often overlooked and therefore may remain unsecured. They increase the risk to the platform by providing additional attack vectors. Failing to disconnect unused protocols can result in a system compromise. The Asynchronous Transfer Mode (ATM) is a protocol operating on network, data link, and physical layers, based on virtual circuits and virtual paths. Disabling ATM protects the system against exploitation of any laws in its implementation.

Description

It is detrimental for operating systems to provide, or install by default, functionality exceeding requirements or mission objectives. These unnecessary capabilities or services are often overlooked and therefore may remain unsecured. They increase the risk to the platform by providing additional attack vectors. Failing to disconnect unused protocols can result in a system compromise. The Asynchronous Transfer Mode (ATM) is a protocol operating on network, data link, and physical layers, based on virtual circuits and virtual paths. Disabling ATM protects the system against exploitation of any laws in its implementation.

STIG	Date
Red Hat Enterprise Linux 8 Security Technical Implementation Guide	2023-12-01

Details

Check Text ( C-33163r942916_chk )
Verify the operating system disables the ability to load the ATM protocol kernel module. $ sudo grep -r atm /etc/modprobe.d/* \| grep "/bin/false" install atm /bin/false If the command does not return any output, or the line is commented out, and use of the ATM protocol is not documented with the Information System Security Officer (ISSO) as an operational requirement, this is a finding. Verify the operating system disables the ability to use the ATM protocol. Check to see if the ATM protocol is disabled with the following command: $ sudo grep -r atm /etc/modprobe.d/* \| grep "blacklist" blacklist atm If the command does not return any output or the output is not "blacklist atm", and use of the ATM protocol is not documented with the ISSO as an operational requirement, this is a finding.

Check Text ( C-33163r942916_chk )

Verify the operating system disables the ability to load the ATM protocol kernel module.

$ sudo grep -r atm /etc/modprobe.d/* | grep "/bin/false"
install atm /bin/false

If the command does not return any output, or the line is commented out, and use of the ATM protocol is not documented with the Information System Security Officer (ISSO) as an operational requirement, this is a finding.

Verify the operating system disables the ability to use the ATM protocol.

Check to see if the ATM protocol is disabled with the following command:

$ sudo grep -r atm /etc/modprobe.d/* | grep "blacklist"
blacklist atm

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

Fix Text (F-33138r942917_fix)
Configure the operating system to disable the ability to use the ATM protocol kernel module. Add or update the following lines in the file "/etc/modprobe.d/blacklist.conf": install atm /bin/false blacklist atm Reboot the system for the settings to take effect.