Guide to the Secure Configuration of SUSE Linux Enterprise 15
Rules, Groups, and Values defined within the XCCDF Benchmark
-
Enforce usage of pam_wheel for su authentication
To ensure that only users who are members of the <code>wheel</code> group can run commands with altered privileges through the <code>su</code> command, make sure that the following line exists in t...Rule Medium Severity -
Secure Session Configuration Files for Login Accounts
When a user logs into a Unix account, the system configures the user's session by reading a number of files. Many of these files are located in the user's home directory, and may have weak permissi...Group -
Maximum login attempts delay
Maximum time in seconds between fail login attempts before re-prompting.Value -
Maximum concurrent login sessions
Maximum number of concurrent sessions by a userValue -
Account Inactivity Timeout (seconds)
In an interactive shell, the value is interpreted as the number of seconds to wait for input after issuing the primary prompt. Bash terminates after waiting for that number of seconds if input does...Value -
Interactive users initialization files
'A regular expression describing a list of file names for files that are sourced at login time for interactive users'Value -
Ensure Home Directories are Created for New Users
All local interactive user accounts, upon creation, should be assigned a home directory. <br> <br> Configure the operating system to assign home directories to all new local interactive use...Rule Medium Severity -
Ensure the Logon Failure Delay is Set Correctly in login.defs
To ensure the logon failure delay controlled by <code>/etc/login.defs</code> is set properly, add or correct the <code>FAIL_DELAY</code> setting in <code>/etc/login.defs</code> to read as follows: ...Rule Medium Severity -
Configure Polyinstantiation of /tmp Directories
To configure polyinstantiated /tmp directories, first create the parent directories which will hold the polyinstantiation child directories. Use the following command: <pre>$ sudo mkdir --mode 000 ...Rule Low Severity -
Configure Polyinstantiation of /var/tmp Directories
To configure polyinstantiated /tmp directories, first create the parent directories which will hold the polyinstantiation child directories. Use the following command: <pre>$ sudo mkdir --mode 000 ...Rule Low Severity -
Set Interactive Session Timeout
Setting the <code>TMOUT</code> option in <code>/etc/profile</code> ensures that all user sessions will terminate based on inactivity. The value of TMOUT should be exported and read only. The <code>...Rule Medium Severity -
User Initialization Files Must Be Group-Owned By The Primary Group
Change the group owner of interactive users files to the group found in <pre>/etc/passwd</pre> for the user. To change the group owner of a local interactive user home directory, use the following ...Rule Medium Severity -
User Initialization Files Must Not Run World-Writable Programs
Set the mode on files being executed by the user initialization files with the following command:$ sudo chmod o-w FILE
Rule Medium Severity -
User Initialization Files Must Be Owned By the Primary User
Set the owner of the user initialization files for interactive users to the primary owner with the following command: <pre>$ sudo chown <i>USER</i> /home/<i>USER</i>/.*</pre> This rule ensures eve...Rule Medium Severity -
Ensure that Users Path Contains Only Local Directories
Ensure that all interactive user initialization files executable search path statements do not contain statements that will reference a working directory other than the users home directory.Rule Medium Severity -
All Interactive Users Must Have A Home Directory Defined
Assign home directories to all interactive users that currently do not have a home directory assigned. This rule checks if the home directory is properly defined in a folder which has at least one...Rule Medium Severity -
All User Files and Directories In The Home Directory Must Be Group-Owned By The Primary Group
Change the group of a local interactive users files and directories to a group that the interactive user is a member of. To change the group owner of a local interactive users files and directories...Rule Medium Severity -
All User Files and Directories In The Home Directory Must Have a Valid Owner
Either remove all files and directories from the system that do not have a valid user, or assign a valid user to all unowned files and directories. To assign a valid owner to a local interactive us...Rule Medium Severity -
All User Files and Directories In The Home Directory Must Have Mode 0750 Or Less Permissive
Set the mode on files and directories in the local interactive user home directory with the following command: <pre>$ sudo chmod 0750 /home/<i>USER</i>/<i>FILE_DIR</i> </pre> Files that beg...Rule Medium Severity -
Ensure users' .netrc Files are not group or world accessible
While the system administrator can establish secure permissions for users' .netrc files, the users can easily override these. This rule ensures every .netrc file or directory under the home direct...Rule Medium Severity -
Ensure users own their home directories
The user home directory is space defined for the particular user to set local environment variables and to store personal files. Since the user is accountable for files stored in the user home dire...Rule Medium Severity -
All Interactive User Home Directories Must Be Group-Owned By The Primary Group
Change the group owner of interactive users home directory to the group found in <code>/etc/passwd</code>. To change the group owner of interactive users home directory, use the following command: ...Rule Medium Severity -
All Interactive User Home Directories Must Be Owned By The Primary User
Change the owner of interactive users home directories to that correct owner. To change the owner of a interactive users home directory, use the following command: <pre>$ sudo chown <i>USER</i> /ho...Rule Medium Severity -
Ensure All User Initialization Files Have Mode 0740 Or Less Permissive
Set the mode of the user initialization files to0740
with the following command:$ sudo chmod 0740 /home/USER/.INIT_FILE
Rule Medium Severity -
All Interactive User Home Directories Must Have mode 0750 Or Less Permissive
Change the mode of interactive users home directories to <code>0750</code>. To change the mode of interactive users home directory, use the following command: <pre>$ sudo chmod 0750 /home/<i>USER</...Rule Medium Severity -
Ensure that No Dangerous Directories Exist in Root's Path
The active path of the root account can be obtained by starting a new root shell and running: <pre># echo $PATH</pre> This will produce a colon-separated list of directories in the path. <br> ...Group -
Ensure that Root's Path Does Not Include World or Group-Writable Directories
For each element in root's path, run:# ls -ld DIR
and ensure that write permissions are disabled for group and other.Rule Medium Severity -
Ensure that Root's Path Does Not Include Relative Paths or Null Directories
Ensure that none of the directories in root's path is equal to a single <code>.</code> character, or that it contains any instances that lead to relative path traversal, such as <code>..</code> or ...Rule Unknown Severity -
Ensure that Users Have Sensible Umask Values
The umask setting controls the default permissions for the creation of new files. With a default <code>umask</code> setting of 077, files and directories created by users will not be readable by an...Group -
Sensible umask
Enter default user umaskValue -
Ensure the Default Bash Umask is Set Correctly
To ensure the default umask for users of the Bash shell is set properly, add or correct the <code>umask</code> setting in <code>/etc/bash.bashrc</code> to read as follows: <pre>umask <xccdf-1.2:sub...Rule Medium Severity -
Ensure the Default C Shell Umask is Set Correctly
To ensure the default umask for users of the C shell is set properly, add or correct the <code>umask</code> setting in <code>/etc/csh.cshrc</code> to read as follows: <pre>umask <xccdf-1.2:sub idre...Rule Medium Severity -
Ensure the Default Umask is Set Correctly in login.defs
To ensure the default umask controlled by <code>/etc/login.defs</code> is set properly, add or correct the <code>UMASK</code> setting in <code>/etc/login.defs</code> to read as follows: <pre>UMASK ...Rule Medium Severity -
Ensure the Default Umask is Set Correctly in /etc/profile
To ensure the default umask controlled by <code>/etc/profile</code> is set properly, add or correct the <code>umask</code> setting in <code>/etc/profile</code> to read as follows: <pre>umask <xccdf...Rule Medium Severity -
Ensure the Default Umask is Set Correctly For Interactive Users
Remove theUMASK
environment variable from all interactive users initialization files.Rule Medium Severity -
System Accounting with auditd
The audit service provides substantial capabilities for recording system activities. By default, the service audits about SELinux AVC denials and certain types of security-relevant events such as s...Group -
Records Events that Modify Date and Time Information
Arbitrary changes to the system time can be used to obfuscate nefarious activities in log files, as well as to confuse network services that are highly dependent upon an accurate system time. All c...Group -
Action for audispd to take when disk is full
The setting for disk_full_action in /etc/audisp/audisp-remote.confValue -
Action for audispd to take when network fails
The setting for network_failure_action in /etc/audisp/audisp-remote.confValue -
AppArmor
Many security vulnerabilities result from bugs in trusted programs. A trusted program runs with privileges that attackers want to possess. The program fails to keep that trust if there is a bug in ...Group -
AppArmor profiles mode
enforce - Set all AppArmor profiles to enforce mode
complain - Set all AppArmor profiles to complain modeValue -
Install the pam_apparmor Package
Thepam_apparmor
package can be installed with the following command:$ sudo zypper install pam_apparmor
Rule Medium Severity -
Resolve information before writing to audit logs
To configure Audit daemon to resolve all uid, gid, syscall, architecture, and socket address information before writing the events to disk, set <code>log_format</code> to <code>ENRICHED</code> in <...Rule Low Severity -
Write Audit Logs to the Disk
To configure Audit daemon to write Audit logs to the disk, setwrite_logs
toyes
in/etc/audit/auditd.conf
. This is the default setting.Rule Medium Severity -
Ensure Users Re-Authenticate for Privilege Escalation - sudo NOPASSWD
The sudo <code>NOPASSWD</code> tag, when specified, allows a user to execute commands using sudo without having to authenticate. This should be disabled by making sure that the <code>NOPASSWD</code...Rule Medium Severity -
Verify that Shared Library Files Have Root Ownership
System-wide shared library files, which are linked to executables during process load time or run time, are stored in the following directories by default: <pre>/lib /lib64 /usr/lib /usr/lib64 </pr...Rule Medium Severity -
Verify Permissions On /etc/sudoers File
To properly set the permissions of/etc/sudoers
, run the command:$ sudo chmod 0440 /etc/sudoers
Rule Medium Severity -
Ensure That the sudo Binary Has the Correct Permissions
To properly set the permissions of/usr/bin/sudo
, run the command:$ sudo chmod 4111 /usr/bin/sudo
Rule Medium Severity -
Ensure sudo passwd_timeout is appropriate - sudo passwd_timeout
The sudo <code>passwd_timeout</code> tag sets the amount of time sudo password prompt waits. The passwd_timeout should be configured by making sure that the <code>passwd_timeout=<xccdf-1.2:sub idre...Rule Medium Severity -
Verify Permissions On /etc/sysctl.d Directory
To properly set the permissions of/etc/sysctl.d
, run the command:$ sudo chmod 0755 /etc/sysctl.d
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.