CIS Ubuntu 20.04 Level 2 Server Benchmark
Rules and Groups employed by this XCCDF Profile
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Remove ufw Package
Theufw
package can be removed with the following command:$ apt-get remove ufw
Rule Medium Severity -
Verify ufw Enabled
Theufw
service can be enabled with the following command:$ sudo systemctl enable ufw.service
Rule Medium Severity -
Ensure ufw Default Deny Firewall Policy
A default deny policy on connections ensures that any unconfigured network usage will be rejected. Note: Any port or protocol without a explicit a...Rule Medium Severity -
Set UFW Loopback Traffic
Configure the loopback interface to accept traffic. Configure all other interfaces to deny traffic to the loopback network.Rule Medium Severity -
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 RDS Support
The Reliable Datagram Sockets (RDS) protocol is a transport layer protocol designed to provide reliable high-bandwidth, low-latency communications ...Rule Low 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 -
Disable TIPC Support
The Transparent Inter-Process Communication (TIPC) protocol is designed to provide communications between nodes in a cluster. To configure the sys...Rule Low Severity -
Wireless Networking
Wireless networking, such as 802.11 (WiFi) and Bluetooth, can present a security risk to sensitive or classified systems and networks. Wireless net...Group -
Disable Wireless Through Software Configuration
If it is impossible to remove the wireless hardware from the device in question, disable as much of it as possible through software. The following ...Group -
Deactivate Wireless Network Interfaces
Deactivating wireless network interfaces should prevent normal usage of the wireless capability. <br><br> Configure the system to disable all wire...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 that All World-Writable Directories Have Sticky Bits Set
When the so-called 'sticky bit' is set on a directory, only the owner of a given file may remove that file from the directory. Without the sticky b...Rule Medium Severity -
Ensure No World-Writable Files Exist
It is generally a good idea to remove global (other) write access to a file when it is discovered. However, check with documentation for specific a...Rule Medium Severity -
Ensure All Files Are Owned by a Group
If any file is not group-owned by a group present in /etc/group, the cause of the lack of group-ownership must be investigated. Following this, tho...Rule Medium Severity -
Ensure All Files Are Owned by a User
If any files are not owned by a user, then the cause of their lack of ownership should be investigated. Following this, the files should be deleted...Rule Medium Severity -
Verify permissions of log files
Any operating system providing too much information in error messages risks compromising the data and security of the structure, and content of err...Rule Medium Severity -
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 Group Who Owns Backup group File
To properly set the group owner of/etc/group-
, run the command:$ sudo chgrp root /etc/group-
Rule Medium Severity -
Verify Group Who Owns Backup gshadow File
To properly set the group owner of/etc/gshadow-
, run the command:$ sudo chgrp shadow /etc/gshadow-
Rule Medium Severity -
Verify Group Who Owns Backup passwd File
To properly set the group owner of/etc/passwd-
, run the command:$ sudo chgrp root /etc/passwd-
Rule Medium Severity -
Verify User Who Owns Backup shadow File
To properly set the group owner of/etc/shadow-
, run the command:$ sudo chgrp shadow /etc/shadow-
Rule Medium Severity -
Verify Group Who Owns group File
To properly set the group owner of/etc/group
, run the command:$ sudo chgrp root /etc/group
Rule Medium Severity -
Verify Group Who Owns gshadow File
To properly set the group owner of/etc/gshadow
, run the command:$ sudo chgrp shadow /etc/gshadow
Rule Medium Severity -
Verify Group Who Owns passwd File
To properly set the group owner of/etc/passwd
, run the command:$ sudo chgrp root /etc/passwd
Rule Medium Severity -
Verify Group Who Owns shadow File
To properly set the group owner of/etc/shadow
, run the command:$ sudo chgrp shadow /etc/shadow
Rule Medium Severity -
Verify User Who Owns Backup group File
To properly set the owner of/etc/group-
, run the command:$ sudo chown root /etc/group-
Rule Medium Severity -
Verify User Who Owns Backup gshadow File
To properly set the owner of/etc/gshadow-
, run the command:$ sudo chown root /etc/gshadow-
Rule Medium Severity -
Verify User Who Owns Backup passwd File
To properly set the owner of/etc/passwd-
, run the command:$ sudo chown root /etc/passwd-
Rule Medium Severity -
Verify Group Who Owns Backup shadow File
To properly set the owner of/etc/shadow-
, run the command:$ sudo chown root /etc/shadow-
Rule Medium Severity -
Verify User Who Owns group File
To properly set the owner of/etc/group
, run the command:$ sudo chown root /etc/group
Rule Medium Severity -
Verify User Who Owns gshadow File
To properly set the owner of/etc/gshadow
, run the command:$ sudo chown root /etc/gshadow
Rule Medium Severity -
Verify User Who Owns passwd File
To properly set the owner of/etc/passwd
, run the command:$ sudo chown root /etc/passwd
Rule Medium Severity -
Verify User Who Owns shadow File
To properly set the owner of/etc/shadow
, run the command:$ sudo chown root /etc/shadow
Rule Medium Severity -
Verify Permissions on Backup group File
To properly set the permissions of/etc/group-
, run the command:$ sudo chmod 0644 /etc/group-
Rule Medium Severity -
Verify Permissions on Backup gshadow File
To properly set the permissions of/etc/gshadow-
, run the command:$ sudo chmod 0640 /etc/gshadow-
Rule Medium Severity -
Verify Permissions on Backup passwd File
To properly set the permissions of/etc/passwd-
, run the command:$ sudo chmod 0644 /etc/passwd-
Rule Medium Severity -
Verify Permissions on Backup shadow File
To properly set the permissions of/etc/shadow-
, run the command:$ sudo chmod 0640 /etc/shadow-
Rule Medium Severity -
Verify Permissions on group File
To properly set the permissions of/etc/group
, run the command:$ sudo chmod 0644 /etc/group
Rule Medium Severity -
Verify Permissions on gshadow File
To properly set the permissions of/etc/gshadow
, run the command:$ sudo chmod 0640 /etc/gshadow
Rule Medium Severity -
Verify Permissions on passwd File
To properly set the permissions of/etc/passwd
, run the command:$ sudo chmod 0644 /etc/passwd
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 -
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 the Automounter
The <code>autofs</code> daemon mounts and unmounts filesystems, such as user home directories shared via NFS, on demand. In addition, autofs can be...Rule Medium Severity -
Disable Mounting of cramfs
To configure the system to prevent the <code>cramfs</code> kernel module from being loaded, add the following line to the file <code>/etc/modprobe...Rule Low Severity -
Disable Mounting of freevxfs
To configure the system to prevent the <code>freevxfs</code> kernel module from being loaded, add the following line to the file <code>/etc/modpro...Rule Low Severity -
Disable Mounting of hfs
To configure the system to prevent the <code>hfs</code> kernel module from being loaded, add the following line to the file <code>/etc/modprobe.d/...Rule Low Severity -
Disable Mounting of hfsplus
To configure the system to prevent the <code>hfsplus</code> kernel module from being loaded, add the following line to the file <code>/etc/modprob...Rule Low 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.