Guide to the Secure Configuration of SUSE Linux Enterprise 15
Rules, Groups, and Values defined within the XCCDF Benchmark
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Require Credential Prompting for Remote Access in GNOME3
By default, <code>GNOME</code> does not require credentials when using <code>Vino</code> for remote access. To configure the system to require remote credentials, add or set <code>authentication-me...Rule Medium Severity -
Require Encryption for Remote Access in GNOME3
By default, <code>GNOME</code> requires encryption when using <code>Vino</code> for remote access. To prevent remote access encryption from being disabled, add or set <code>require-encryption</code...Rule Medium Severity -
Screensaver Inactivity timeout
Choose allowed duration (in seconds) of inactive graphical sessionsValue -
Screensaver Lock Delay
Choose allowed duration (in seconds) after a screensaver becomes active before displaying an authentication promptValue -
Enable GNOME3 Screensaver Idle Activation
To activate the screensaver in the GNOME3 desktop after a period of inactivity, add or set <code>idle-activation-enabled</code> to <code>true</code> in <code>/etc/dconf/db/local.d/00-security-setti...Rule Medium Severity -
Enable GNOME3 Screensaver Lock After Idle Period
To activate locking of the screensaver in the GNOME3 desktop when it is activated, run the following command to configure the SUSE operating system to allow the user to lock the GUI: <pre>gsetting...Rule Medium Severity -
Ensure Users Cannot Change GNOME3 Session Idle Settings
If not already configured, ensure that users cannot change GNOME3 session idle settings by adding <code>/org/gnome/desktop/session/idle-delay</code> to <code>/etc/dconf/db/local.d/locks/00-security...Rule Medium Severity -
Sudo
<code>Sudo</code>, which stands for "su 'do'", provides the ability to delegate authority to certain users, groups of users, or system administrators. When configured for system users and/or groups...Group -
Group name dedicated to the use of sudo
Specify the name of the group that should own /usr/bin/sudo.Value -
Sudo - logfile value
Specify the sudo logfile to use. The default value used here matches the example location from CIS, which uses /var/log/sudo.log.Value -
Sudo - passwd_timeout value
Defines the number of minutes before thesudopassword prompt times out. Defining 0 means no timeout. The default timeout value is 5 minutes.Value -
Sudo - timestamp_timeout value
Defines the number of minutes that can elapse before <code>sudo</code> will ask for a passwd again. If set to a value less than 0 the user's time stamp will never expire. Defining 0 means always pr...Value -
Sudo - umask value
Specify the sudo umask to use. The actual umask value that is used is the union of the user's umask and the sudo umask. The default sudo umask is 0022. This guarantess sudo never lowers the umask w...Value -
Ensure sudo Runs In A Minimal Environment - sudo env_reset
The sudo <code>env_reset</code> tag, when specified, will run the command in a minimal environment, containing the TERM, PATH, HOME, MAIL, SHELL, LOGNAME, USER and SUDO_* variables. This should be ...Rule Medium Severity -
Ensure sudo Ignores Commands In Current Dir - sudo ignore_dot
The sudo <code>ignore_dot</code> tag, when specified, will ignore the current directory in the PATH environment variable. This should be enabled by making sure that the <code>ignore_dot</code> tag ...Rule Medium Severity -
Ensure Privileged Escalated Commands Cannot Execute Other Commands - sudo NOEXEC
The sudo <code>NOEXEC</code> tag, when specified, prevents user executed commands from executing other commands, like a shell for example. This should be enabled by making sure that the <code>NOEXE...Rule High Severity -
Ensure Only Users Logged In To Real tty Can Execute Sudo - sudo requiretty
The sudo <code>requiretty</code> tag, when specified, will only execute sudo commands from users logged in to a real tty. This should be enabled by making sure that the <code>requiretty</code> tag ...Rule Medium Severity -
Ensure sudo umask is appropriate - sudo umask
The sudo <code>umask</code> tag, when specified, will be added the to the user's umask in the command environment. The umask should be configured by making sure that the <code>umask=<xccdf-1.2:sub ...Rule Medium Severity -
Ensure Only Users Logged In To Real tty Can Execute Sudo - sudo use_pty
The sudo <code>use_pty</code> tag, when specified, will only execute sudo commands from users logged in to a real tty. This should be enabled by making sure that the <code>use_pty</code> tag exists...Rule Medium Severity -
Ensure Sudo Logfile Exists - sudo logfile
A custom log sudo file can be configured with the 'logfile' tag. This rule configures a sudo custom logfile at the default location suggested by CIS, which uses /var/log/sudo.log.Rule Low Severity -
Ensure a dedicated group owns sudo
Restrict the execution of privilege escalated commands to a dedicated group of users. Ensure the group owner of /usr/bin/sudo is <xccdf-1.2:sub xmlns:xccdf-1.2="http://checklists.nist.gov/xccdf/1.2...Rule Medium Severity -
Ensure Users Re-Authenticate for Privilege Escalation - sudo !authenticate
The sudo <code>!authenticate</code> option, when specified, allows a user to execute commands using sudo without having to authenticate. This should be disabled by making sure that the <code>!authe...Rule Medium Severity -
Ensure Users Re-Authenticate for Privilege Escalation - sudo
The sudo <code>NOPASSWD</code> and <code>!authenticate</code> option, when specified, allows a user to execute commands using sudo without having to authenticate. This should be disabled by making ...Rule Medium Severity -
The operating system must restrict privilege elevation to authorized personnel
The sudo command allows a user to execute programs with elevated (administrator) privileges. It prompts the user for their password and confirms your request to execute a command by checking a file...Rule Medium Severity -
Only the VDSM User Can Use sudo NOPASSWD
The sudo <code>NOPASSWD</code> tag, when specified, allows a user to execute commands using sudo without having to authenticate. Only the <code>vdsm</code> user should have this capability in any s...Rule Medium Severity -
Ensure sudo only includes the default configuration directory
Administrators can configure authorized <code>sudo</code> users via drop-in files, and it is possible to include other directories and configuration files from the file currently being parsed. Mak...Rule Medium Severity -
Explicit arguments in sudo specifications
All commands in the sudoers file must strictly specify the arguments allowed to be used for a given user. If the command is supposed to be executed only without arguments, pass "" as an argument in...Rule Medium Severity -
Don't define allowed commands in sudoers by means of exclusion
Policies applied by sudo through the sudoers file should not involve negation. Each user specification in the <code>sudoers</code> file contains a comma-delimited list of command specifications. T...Rule Medium Severity -
Don't target root user in the sudoers file
The targeted users of a user specification should be, as much as possible, non privileged users (i.e.: non-root). User specifications have to explicitly list the runas spec (i.e. the list of targe...Rule Medium Severity -
System Tooling / Utilities
The following checks evaluate the system for recommended base packages -- both for installation and removal.Group -
Ensure gnutls-utils is installed
Thegnutls-utilspackage can be installed with the following command:$ sudo zypper install gnutls-utils
Rule Medium Severity -
Ensure nss-tools is installed
Thenss-toolspackage can be installed with the following command:$ sudo zypper install nss-tools
Rule Medium Severity -
Updating Software
The <code>zypper</code> command line tool is used to install and update software packages. The system also provides a graphical software update tool in the <b>System</b> menu, in the <b>Administrat...Group -
Install dnf-automatic Package
Thednf-automaticpackage can be installed with the following command:$ sudo zypper install dnf-automatic
Rule Medium Severity -
Ensure zypper Removes Previous Package Versions
<code>zypper</code> should be configured to remove previous software components after new versions have been installed. To configure <code>zypper</code> to remove the previous software components ...Rule Low Severity -
Configure dnf-automatic to Install Available Updates Automatically
To ensure that the packages comprising the available updates will be automatically installed by <code>dnf-automatic</code>, set <code>apply_updates</code> to <code>yes</code> under <code>[commands]...Rule Medium Severity -
Configure dnf-automatic to Install Only Security Updates
To configure <code>dnf-automatic</code> to install only security updates automatically, set <code>upgrade_type</code> to <code>security</code> under <code>[commands]</code> section in <code>/etc/dn...Rule Low Severity -
Ensure gpgcheck Enabled In Main zypper Configuration
The <code>gpgcheck</code> option controls whether RPM packages' signatures are always checked prior to installation. To configure zypper to check package signatures before installing them, ensure t...Rule High Severity -
Ensure gpgcheck Enabled for All zypper Package Repositories
To ensure signature checking is not disabled for any repos, remove any lines from files in/etc/yum.repos.dof the form:gpgcheck=0
Rule High Severity -
Ensure package manager repositories are configured
Systems need to have package manager repositories configured to ensure they receive the latest patches and updates.Rule Medium Severity -
Ensure SUSE GPG Key Installed
To ensure the system can cryptographically verify base software packages come from SUSE (and to connect to the SUSE to receive them), the SUSE GPG key must properly be installed. To install the SUS...Rule High Severity -
Ensure Software Patches Installed
If the system is configured for online updates, invoking the following command will list available security updates: <pre>$ sudo zypper refresh && sudo zypper list-patches -g security</pre...Rule Medium Severity -
Account and Access Control
In traditional Unix security, if an attacker gains shell access to a certain login account, they can perform any action or access any file to which that account has access. Therefore, making it mor...Group -
Authselect profile
Specify the authselect profile to selectValue -
Login Banner Verbiage
Enter an appropriate login banner for your organization. Please note that new lines must be expressed by the '\n' character and special characters like parentheses and quotation marks must be escap...Value -
MotD Banner Verbiage
Enter an appropriate login banner for your organization. Please note that new lines must be expressed by the '\n' character and special characters like parentheses and quotation marks must be escap...Value -
Remote Login Banner Verbiage
Enter an appropriate login banner for your organization. Please note that new lines must be expressed by the '\n' character and special characters like parentheses and quotation marks must be escap...Value -
Modify the System Login Banner for Remote Connections
To configure the system login banner edit <code>/etc/issue.net</code>. Replace the default text with a message compliant with the local site policy or a legal disclaimer. The DoD required text is ...Rule Medium Severity -
Verify Group Ownership of System Login Banner
To properly set the group owner of/etc/issue, run the command:$ sudo chgrp root /etc/issue
Rule Medium Severity -
Verify Group Ownership of System Login Banner for Remote Connections
To properly set the group owner of/etc/issue.net, run the command:$ sudo chgrp root /etc/issue.net
Rule Medium Severity
Node 2
The content of the drawer really is up to you. It could have form fields, definition lists, text lists, labels, charts, progress bars, etc. Spacing recommendation is 24px margins. You can put tabs in here, and can also make the drawer scrollable.