Guide to the Secure Configuration of Ubuntu 20.04
Rules, Groups, and Values defined within the XCCDF Benchmark
-
Ensure PAM Enforces Password Requirements - Minimum Different Categories
The pam_pwquality module's <code>minclass</code> parameter controls requirements for usage of different character classes, or types, of character t...Rule Medium Severity -
Ensure PAM Enforces Password Requirements - Minimum Length
The pam_pwquality module's <code>minlen</code> parameter controls requirements for minimum characters required in a password. Add <code>minlen=<xcc...Rule Medium Severity -
Ensure PAM Enforces Password Requirements - Minimum Special Characters
The pam_pwquality module's <code>ocredit=</code> parameter controls requirements for usage of special (or "other") characters in a password. When s...Rule Medium Severity -
Ensure PAM Enforces Password Requirements - Authentication Retry Prompts Permitted Per-Session
To configure the number of retry prompts that are permitted per-session: Edit the <code>pam_pwquality.so</code> statement in <code>/etc/pam.d/com...Rule Medium Severity -
Ensure PAM Enforces Password Requirements - Minimum Uppercase Characters
The pam_pwquality module's <code>ucredit=</code> parameter controls requirements for usage of uppercase letters in a password. When set to a negati...Rule Medium Severity -
Set Password Hashing Algorithm
The system's default algorithm for storing password hashes in/etc/shadowis SHA-512. This can be configured in several locations.Group -
Set Password Hashing Algorithm in /etc/login.defs
In <code>/etc/login.defs</code>, add or correct the following line to ensure the system will use <xccdf-1.2:sub idref="xccdf_org.ssgproject.content...Rule Medium Severity -
Protect Physical Console Access
It is impossible to fully protect a system from an attacker with physical access, so securing the space in which the system is located should be co...Group -
Login timeout for idle sessions
Specify duration of allowed idle time.Value -
Disable Ctrl-Alt-Del Burst Action
By default, <code>SystemD</code> will reboot the system if the <code>Ctrl-Alt-Del</code> key sequence is pressed Ctrl-Alt-Delete more than 7 times ...Rule High Severity -
Disable Ctrl-Alt-Del Reboot Activation
By default, <code>SystemD</code> will reboot the system if the <code>Ctrl-Alt-Del</code> key sequence is pressed. <br><br> To configure the system ...Rule High Severity -
Configure Screen Locking
When a user must temporarily leave an account logged-in, screen locking should be employed to prevent passersby from abusing the account. User educ...Group -
Configure Console Screen Locking
A console screen locking mechanism is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the in...Group -
Check that vlock is installed to allow session locking
The Ubuntu 20.04 operating system must have vlock installed to allow for session locking. The <code>vlock</code> package can be installed with th...Rule Medium Severity -
Hardware Tokens for Authentication
The use of hardware tokens such as smart cards for system login provides stronger, two-factor authentication than using a username and password. I...Group -
OpenSC Smart Card Drivers
Choose the Smart Card Driver in use by your organization. <br>For DoD, choose the <code>cac</code> driver. <br>If your driver is not listed and you...Value -
Install the opensc Package For Multifactor Authentication
Theopensc-pkcs11package can be installed with the following command:$ apt-get install opensc-pkcs11
Rule Medium Severity -
Install Smart Card Packages For Multifactor Authentication
Configure the operating system to implement multifactor authentication by installing the required package with the following command: The <code>li...Rule Medium Severity -
Configure Smart Card Certificate Authority Validation
Configure the operating system to do certificate status checking for PKI authentication. Modify all of the <code>cert_policy</code> lines in <code>...Rule Medium Severity -
Configure Smart Card Certificate Status Checking
Configure the operating system to do certificate status checking for PKI authentication. Modify all of the <code>cert_policy</code> lines in <code>...Rule Medium Severity -
Configure Smart Card Local Cache of Revocation Data
Configure the operating system for PKI-based authentication to use local revocation data when unable to access the network to obtain it remotely. M...Rule Medium Severity -
Verify that 'use_mappers' is set to 'pwent' in PAM
The operating system must map the authenticated identity to the user or group account for PKI-based authentication. Verify that <code>use_mappers<...Rule Low Severity -
Protect Accounts by Restricting Password-Based Login
Conventionally, Unix shell accounts are accessed by providing a username and password to a login program, which tests these values for correctness ...Group -
Accounts Authorized Local Users on the Operating System
List the user accounts that are authorized locally on the operating system. This list includes both users requried by the operating system and by t...Value -
Ensure All Accounts on the System Have Unique User IDs
Change user IDs (UIDs), or delete accounts, so each has a unique name.Rule Medium Severity -
Ensure All Groups on the System Have Unique Group ID
Change the group name or delete groups, so each has a unique id.Rule Medium Severity -
Ensure All Groups on the System Have Unique Group Names
Change the group name or delete groups, so each has a unique name.Rule Medium Severity -
Set Account Expiration Parameters
Accounts can be configured to be automatically disabled after a certain time period, meaning that they will require administrator interaction to be...Group -
number of days after the last login of the user when the user will be locked out
'This option is specific for the auth or account phase. It specifies the number of days after the last login of the user when the user will be lock...Value -
number of days after a password expires until the account is permanently disabled
The number of days to wait after a password expires, until the account will be permanently disabled.Value -
Set Account Expiration Following Inactivity
To specify the number of days after a password expires (which signifies inactivity) until an account is permanently disabled, add or correct the fo...Rule Medium Severity -
Assign Expiration Date to Temporary Accounts
Temporary accounts are established as part of normal account activation procedures when there is a need for short-term accounts. In the event tempo...Rule Medium Severity -
Ensure All Accounts on the System Have Unique Names
Ensure accounts on the system have unique names. To ensure all accounts have unique names, run the following command: <pre>$ sudo getent passwd | ...Rule Medium Severity -
Use Centralized and Automated Authentication
Implement an automated system for managing user accounts that minimizes the risk of errors, either intentional or deliberate. This system should in...Rule Medium Severity -
Ensure shadow Group is Empty
The shadow group allows system programs which require access the ability to read the /etc/shadow file. No users should be assigned to the shadow gr...Rule Medium Severity -
Policy Requires Immediate Change of Temporary Passwords
Temporary passwords for Ubuntu 20.04 operating system logons must require an immediate change to a permanent password. Verify that a policy exists...Rule Medium Severity -
Set Password Expiration Parameters
The file <code>/etc/login.defs</code> controls several password-related settings. Programs such as <code>passwd</code>, <code>su</code>, and <code>...Group -
maximum password age
Maximum age of password in daysValue -
minimum password age
Minimum age of password in daysValue -
minimum password length
Minimum number of characters in passwordValue -
warning days before password expires
The number of days' warning given before a password expires.Value -
Set Password Maximum Age
To specify password maximum age for new accounts, edit the file <code>/etc/login.defs</code> and add or correct the following line: <pre>PASS_MAX_D...Rule Medium Severity -
Set Password Minimum Age
To specify password minimum age for new accounts, edit the file <code>/etc/login.defs</code> and add or correct the following line: <pre>PASS_MIN_D...Rule Medium Severity -
Set Password Minimum Length in login.defs
To specify password length requirements for new accounts, edit the file <code>/etc/login.defs</code> and add or correct the following line: <pre>PA...Rule Medium Severity -
Set Existing Passwords Maximum Age
Configure non-compliant accounts to enforce a <xccdf-1.2:sub idref="xccdf_org.ssgproject.content_value_var_accounts_maximum_age_login_defs" use="le...Rule Medium Severity -
Offload audit Logs to External Media
The operating system must have a crontab script running weekly to offload audit events of standalone systems.Rule Medium Severity -
Set Existing Passwords Minimum Age
Configure non-compliant accounts to enforce a 24 hours/1 day minimum password lifetime by running the following command: <pre>$ sudo chage -m 1 <i>...Rule Medium Severity -
Set Password Warning Age
To specify how many days prior to password expiration that a warning will be issued to users, edit the file <code>/etc/login.defs</code> and add or...Rule Medium Severity -
Verify Proper Storage and Existence of Password Hashes
By default, password hashes for local accounts are stored in the second field (colon-separated) in <code>/etc/shadow</code>. This file should be re...Group -
Password Hashing algorithm
Specify the number of SHA rounds for the system password encryption algorithm. Defines the value set in <code>/etc/pam.d/system-auth</code> and <co...Value
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.