Skip to content
Log In

Guide to the Secure Configuration of Debian 11

Rules, Groups, and Values defined within the XCCDF Benchmark

  • Configure NFS Servers

    The steps in this section are appropriate for systems which operate as NFS servers.
    Group
    Show

  • Ensure All-Squashing Disabled On All Exports

    The <code>all_squash</code> maps all uids and gids to an anonymous user. This should be disabled by removing any instances of the <code>all_squash</code> option from the file <code>/etc/exports</co...
    Rule Low Severity
    Show

  • Disable SSH Server If Possible

    The SSH server service, sshd, is commonly needed. However, if it can be disabled, do so. This is unusual, as SSH is a common method for encrypted and authenticated remote access.
    Rule High Severity
    Show

  • 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 unpredictably on unmanaged systems. Central time protocols can...
    Group
    Show

  • Vendor Approved Time Servers

    The list of vendor-approved time servers
    Value
    Show

  • Install the ntp service

    The ntpd service should be installed.
    Rule High Severity
    Show

  • The Chronyd service is enabled

    chrony is a daemon which implements the Network Time Protocol (NTP) is designed to synchronize system clocks across a variety of systems and use a source that is highly accurate. More information o...
    Rule Medium Severity
    Show

  • Enable the NTP Daemon

    The ntp service can be enabled with the following command: 
    $ sudo systemctl enable ntp.service
    Rule High Severity
    Show

  • Ensure Chrony is only configured with the server directive

    Check that Chrony only has time sources configured with the server directive.
    Rule Medium Severity
    Show

  • A remote time server for Chrony is configured

    <code>Chrony</code> is a daemon which implements the Network Time Protocol (NTP). It is designed to synchronize system clocks across a variety of systems and use a source that is highly accurate. M...
    Rule Medium Severity
    Show

  • Rlogin, Rsh, and Rexec

    The Berkeley r-commands are legacy services which allow cleartext remote access and have an insecure trust model.
    Group
    Show

  • Remove Rsh Trust Files

    The files <code>/etc/hosts.equiv</code> and <code>~/.rhosts</code> (in each user's home directory) list remote hosts and users that are trusted by the local system when using the rshd daemon. To re...
    Rule High Severity
    Show

  • SNMP Server

    The Simple Network Management Protocol allows administrators to monitor the state of network devices, including computers. Older versions of SNMP were well-known for weak security, such as plaintex...
    Group
    Show

  • Disable SNMP Server if Possible

    The system includes an SNMP daemon that allows for its remote monitoring, though it not installed by default. If it was installed and activated but is not needed, the software should be disabled an...
    Group
    Show

  • Disable snmpd Service

    The snmpd service can be disabled with the following command: 
    $ sudo systemctl mask --now snmpd.service
    Rule Low Severity
    Show

  • Verify Group Ownership on SSH Server Private *_key Key Files

    SSH server private keys, files that match the /etc/ssh/*_key glob, must be group-owned by root group.
    Rule Medium Severity
    Show

  • SNMP read-only community string

    Specify the SNMP community string used for read-only access.
    Value
    Show

  • SNMP read-write community string

    Specify the SNMP community string used for read-write access.
    Value
    Show

  • Ensure Default SNMP Password Is Not Used

    Edit <code>/etc/snmp/snmpd.conf</code>, remove or change the default community strings of <code>public</code> and <code>private</code>. This profile configures new read-only community string to <co...
    Rule High Severity
    Show

  • SSH Server

    The SSH protocol is recommended for remote login and remote file transfer. SSH provides confidentiality and integrity for data exchanged between two systems, as well as server authentication, throu...
    Group
    Show

  • SSH session Idle time

    Specify duration of allowed idle time.
    Value
    Show

  • SSH Max authentication attempts

    Specify the maximum number of authentication attempts per connection.
    Value
    Show

  • SSH is required to be installed

    Specify if the Policy requires SSH to be installed. Used by SSH Rules to determine if SSH should be uninstalled or configured.<br> A value of 0 means that the policy doesn't care if OpenSSH server ...
    Value
    Show

  • SSH Max Sessions Count

    Specify the maximum number of open sessions permitted.
    Value
    Show

  • SSH Max Keep Alive Count

    Specify the maximum number of idle message counts before session is terminated.
    Value
    Show

  • Install the OpenSSH Server Package

    The openssh-server package should be installed. The openssh-server package can be installed with the following command: 
    $ apt-get install openssh-server
    Rule Medium Severity
    Show

  • Remove the OpenSSH Server Package

    The openssh-server package should be removed. The openssh-server package can be removed with the following command: 
    $ apt-get remove openssh-server
    Rule Medium Severity
    Show

  • Verify Group Ownership on SSH Server Public *.pub Key Files

    SSH server public keys, files that match the /etc/ssh/*.pub glob, must be group-owned by root group.
    Rule Medium Severity
    Show

  • Verify Ownership on SSH Server Private *_key Key Files

    SSH server private keys, files that match the /etc/ssh/*_key glob, must be owned by root user.
    Rule Medium Severity
    Show

  • Verify Ownership on SSH Server Public *.pub Key Files

    SSH server public keys, files that match the /etc/ssh/*.pub glob, must be owned by root user.
    Rule Medium Severity
    Show

  • Verify Permissions on SSH Server Private *_key Key Files

    SSH server private keys - files that match the <code>/etc/ssh/*_key</code> glob, have to have restricted permissions. If those files are owned by the <code>root</code> user and the <code>root</code...
    Rule Medium Severity
    Show

  • 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_config</code>. The following recommendations can be app...
    Group
    Show

  • SSH RekeyLimit - size

    Specify the size component of the rekey limit.
    Value
    Show

  • SSH RekeyLimit - size

    Specify the size component of the rekey limit.
    Value
    Show

  • SSH Compression Setting

    Specify the compression setting for SSH connections.
    Value
    Show

  • SSH Privilege Separation Setting

    Specify whether and how sshd separates privileges when handling incoming network connections.
    Value
    Show

  • SSH LoginGraceTime setting

    Configure parameters for how long the servers stays connected before the user has successfully logged in
    Value
    Show

  • SSH MaxStartups setting

    Configure parameters for maximum concurrent unauthenticated connections to the SSH daemon.
    Value
    Show

  • 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 option <code>ClientAliveInterval</code> configures time...
    Rule Medium Severity
    Show

  • Set SSH Client Alive Count Max

    The SSH server sends at most <code>ClientAliveCountMax</code> messages during a SSH session and waits for a response from the SSH client. The option <code>ClientAliveInterval</code> configures time...
    Rule Medium Severity
    Show

  • Disable Host-Based Authentication

    SSH's cryptographic host-based authentication is more secure than <code>.rhosts</code> authentication. However, it is not recommended that hosts unilaterally trust one another, even within an organ...
    Rule Medium Severity
    Show

  • Allow Only SSH Protocol 2

    Only SSH protocol version 2 connections should be permitted. The default setting in <code>/etc/ssh/sshd_config</code> is correct, and can be verified by ensuring that the following line appears: <p...
    Rule High Severity
    Show

  • Disable Compression Or Set Compression to delayed

    Compression is useful for slow network connections over long distances but can cause performance issues on local LANs. If use of compression is required, it should be enabled only after a user has ...
    Rule Medium Severity
    Show

  • Disable SSH Access via Empty Passwords

    Disallow SSH login with empty passwords. The default SSH configuration disables logins with empty passwords. The appropriate configuration is used if no value is set for <code>PermitEmptyPasswords<...
    Rule High Severity
    Show

  • Disable GSSAPI Authentication

    Unless needed, SSH should not permit extraneous or unnecessary authentication mechanisms like GSSAPI. <br> The default SSH configuration disallows authentications based on GSSAPI. The appropriate c...
    Rule Medium Severity
    Show

  • Disable Kerberos Authentication

    Unless needed, SSH should not permit extraneous or unnecessary authentication mechanisms like Kerberos. <br> The default SSH configuration disallows authentication validation through Kerberos. The ...
    Rule Medium Severity
    Show

  • Disable PubkeyAuthentication Authentication

    Unless needed, SSH should not permit extraneous or unnecessary authentication mechanisms. To disable PubkeyAuthentication authentication, add or correct the following line in <code>/etc/ssh/sshd_...
    Rule Medium Severity
    Show

  • Disable SSH Support for .rhosts Files

    SSH can emulate the behavior of the obsolete rsh command in allowing users to enable insecure access to their accounts via <code>.rhosts</code> files. <br> The default SSH configuration disables su...
    Rule Medium Severity
    Show

  • Disable SSH root Login with a Password (Insecure)

    To disable password-based root logins over SSH, add or correct the following line in /etc/ssh/sshd_config: 
    PermitRootLogin prohibit-password
    Rule Medium Severity
    Show

  • Disable SSH TCP Forwarding

    The <code>AllowTcpForwarding</code> parameter specifies whether TCP forwarding is permitted. To disable TCP forwarding, add or correct the following line in <code>/etc/ssh/sshd_config</code>: <p...
    Rule Medium Severity
    Show

Node 2

siemur/test-space

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.

Capacity
Modules