Public Cloud Hardening for SUSE Linux Enterprise 15
Rules and Groups employed by this XCCDF Profile
-
Record Attempts to Alter Time Through clock_settime
If the <code>auditd</code> daemon is configured to use the <code>augenrules</code> program to read audit rules during daemon startup (the default),...Rule Medium Severity -
Record attempts to alter time through settimeofday
If the <code>auditd</code> daemon is configured to use the <code>augenrules</code> program to read audit rules during daemon startup (the default),...Rule Medium Severity -
Record Attempts to Alter Time Through stime
If the <code>auditd</code> daemon is configured to use the <code>augenrules</code> program to read audit rules during daemon startup (the default),...Rule Medium Severity -
Record Attempts to Alter the localtime File
If the <code>auditd</code> daemon is configured to use the <code>augenrules</code> program to read audit rules during daemon startup (the default),...Rule Medium Severity -
Configure auditd Data Retention
The audit system writes data to <code>/var/log/audit/audit.log</code>. By default, <code>auditd</code> rotates 5 logs by size (6MB), retaining a ma...Group -
Encrypt Audit Records Sent With audispd Plugin
Configure the operating system to encrypt the transfer of off-loaded audit records onto a different system or media from the system being audited. ...Rule Medium Severity -
Configure auditd Disk Full Action when Disk Space Is Full
The <code>auditd</code> service can be configured to take an action when disk space is running low but prior to running out of space completely. Ed...Rule Medium Severity -
Configure auditd admin_space_left Action on Low Disk Space
The <code>auditd</code> service can be configured to take an action when disk space is running low but prior to running out of space completely. Ed...Rule Medium Severity -
Configure auditd max_log_file_action Upon Reaching Maximum Log Size
The default action to take when the logs reach their maximum size is to rotate the log files, discarding the oldest one. To configure the action ta...Rule Medium Severity -
Configure auditd space_left on Low Disk Space
The <code>auditd</code> service can be configured to take an action when disk space is running low but prior to running out of space completely. Ed...Rule Medium Severity -
Configure auditd space_left Action on Low Disk Space
The <code>auditd</code> service can be configured to take an action when disk space <i>starts</i> to run low. Edit the file <code>/etc/audit/auditd...Rule Medium Severity -
Configure Syslog
The syslog service has been the default Unix logging mechanism for many years. It has a number of downsides, including inconsistent log format, lac...Group -
systemd-journald
systemd-journald is a system service that collects and stores logging data. It creates and maintains structured, indexed journals based on logging ...Group -
Ensure journald is configured to compress large log files
The journald system can compress large log files to avoid fill the system disk.Rule Medium Severity -
Ensure journald is configured to write log files to persistent disk
The journald system may store log files in volatile memory or locally on disk. If the logs are only stored in volatile memory they will we lost upo...Rule Medium Severity -
Network Configuration and Firewalls
Most systems must be connected to a network of some sort, and this brings with it the substantial risk of network attack. This section discusses th...Group -
Uncommon Network Protocols
The system includes support for several network protocols which are not commonly used. Although security vulnerabilities in kernel networking code ...Group -
Disable DCCP Support
The Datagram Congestion Control Protocol (DCCP) is a relatively new transport layer protocol, designed to support streaming media and telephony. T...Rule Medium Severity -
Disable SCTP Support
The Stream Control Transmission Protocol (SCTP) is a transport layer protocol, designed to support the idea of message-oriented communication, with...Rule Medium Severity -
File Permissions and Masks
Traditional Unix security relies heavily on file and directory permissions to prevent unauthorized users from reading or modifying files to which t...Group -
Verify Permissions on Important Files and Directories
Permissions for many files on a system must be set restrictively to ensure sensitive information is properly protected. This section discusses impo...Group -
Verify Permissions on Files with Local Account Information and Credentials
The default restrictive permissions for files which act as important security databases such as <code>passwd</code>, <code>shadow</code>, <code>gro...Group -
Verify Permissions and Ownership of Old Passwords File
To properly set the owner of <code>/etc/security/opasswd</code>, run the command: <pre>$ sudo chown root /etc/security/opasswd </pre> To properly ...Rule Medium Severity -
Verify Permissions on Backup shadow File
To properly set the permissions of/etc/shadow-
, run the command:$ sudo chmod 0000 /etc/shadow-
Rule Medium Severity -
Verify Permissions on shadow File
To properly set the permissions of/etc/shadow
, run the command:$ sudo chmod 0640 /etc/shadow
Rule Medium Severity -
Verify File Permissions Within Some Important Directories
Some directories contain files whose confidentiality or integrity is notably important and may also be susceptible to misconfiguration over time, p...Group -
Verify that system commands files are group owned by root or a system account
System commands files are stored in the following directories by default: <pre>/bin /sbin /usr/bin /usr/sbin /usr/local/bin /usr/local/sbin </pre> ...Rule Medium Severity -
Restrict Dynamic Mounting and Unmounting of Filesystems
Linux includes a number of facilities for the automated addition and removal of filesystems on a running system. These facilities may be necessary...Group -
Disable Mounting of squashfs
To configure the system to prevent the <code>squashfs</code> kernel module from being loaded, add the following line to the file <code>/etc/modpro...Rule Low Severity -
Disable Mounting of udf
To configure the system to prevent the <code>udf</code> kernel module from being loaded, add the following line to the file <code>/etc/modprobe.d/...Rule Low Severity -
Disable Modprobe Loading of USB Storage Driver
To prevent USB storage devices from being used, configure the kernel module loading system to prevent automatic loading of the USB storage driver. ...Rule Medium Severity -
Restrict Programs from Dangerous Execution Patterns
The recommendations in this section are designed to ensure that the system's features to protect against potentially dangerous program execution ar...Group -
Disable Core Dumps
A core dump file is the memory image of an executable program when it was terminated by the operating system due to errant behavior. In most cases,...Group -
Disable Core Dumps for All Users
To disable core dumps for all users, add the following line to <code>/etc/security/limits.conf</code>, or to a file within the <code>/etc/security/...Rule Medium Severity -
Services
The best protection against vulnerable software is running less software. This section describes how to review the software which SUSE Linux Enterp...Group -
Cron and At Daemons
The cron and at services are used to allow commands to be executed at a later time. The cron service is required by almost all systems to perform n...Group -
Verify Permissions on cron.d
To properly set the permissions of/etc/cron.d
, run the command:$ sudo chmod 0700 /etc/cron.d
Rule Medium Severity -
Verify Permissions on cron.daily
To properly set the permissions of/etc/cron.daily
, run the command:$ sudo chmod 0700 /etc/cron.daily
Rule Medium Severity -
Verify Permissions on cron.hourly
To properly set the permissions of/etc/cron.hourly
, run the command:$ sudo chmod 0700 /etc/cron.hourly
Rule Medium Severity -
Verify Permissions on cron.monthly
To properly set the permissions of/etc/cron.monthly
, run the command:$ sudo chmod 0700 /etc/cron.monthly
Rule Medium Severity -
Verify Permissions on cron.weekly
To properly set the permissions of/etc/cron.weekly
, run the command:$ sudo chmod 0700 /etc/cron.weekly
Rule Medium Severity -
Network Time Protocol
The Network Time Protocol is used to manage the system clock over a network. Computer clocks are not very accurate, so time will drift unpredictabl...Group -
Ensure that chronyd is running under chrony user account
chrony is a daemon which implements the Network Time Protocol (NTP). It is designed to synchronize system clocks across a variety of systems and us...Rule Medium Severity -
SSH Server
The SSH protocol is recommended for remote login and remote file transfer. SSH provides confidentiality and integrity for data exchanged between tw...Group -
Verify Permissions on SSH Server config file
To properly set the permissions of/etc/ssh/sshd_config
, run the command:$ sudo chmod 0600 /etc/ssh/sshd_config
Rule Medium Severity -
Configure OpenSSH Server if Necessary
If the system needs to act as an SSH server, then certain changes should be made to the OpenSSH daemon configuration file <code>/etc/ssh/sshd_confi...Group -
Set SSH Client Alive Count Max to zero
The SSH server sends at most <code>ClientAliveCountMax</code> messages during a SSH session and waits for a response from the SSH client. The optio...Rule Medium Severity -
Set SSH Client Alive Interval
SSH allows administrators to set a network responsiveness timeout interval. After this interval has passed, the unresponsive client will be automat...Rule Medium Severity -
Disable SSH Root Login
The root user should never be allowed to login to a system directly over a network. To disable root login via SSH, add or correct the following lin...Rule Medium Severity -
Disable SSH TCP Forwarding
The <code>AllowTcpForwarding</code> parameter specifies whether TCP forwarding is permitted. To disable TCP forwarding, add or correct the followin...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.