Skip to content
Log In

Guide to the Secure Configuration of Alibaba Cloud Linux 3

Rules, Groups, and Values defined within the XCCDF Benchmark

  • Verify Owner on crontab

    To properly set the owner of /etc/crontab, run the command: 
    $ sudo chown root /etc/crontab
    Rule Medium Severity
    Show

  • 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
    Show

  • 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
    Show

  • 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
    Show

  • 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
    Show

  • Verify Permissions on crontab

    To properly set the permissions of /etc/crontab, run the command: 
    $ sudo chmod 0600 /etc/crontab
    Rule Medium Severity
    Show

  • Ensure that /etc/at.deny does not exist

    The file /etc/at.deny should not exist. Use /etc/at.allow instead.
    Rule Medium Severity
    Show

  • Ensure that /etc/cron.deny does not exist

    The file /etc/cron.deny should not exist. Use /etc/cron.allow instead.
    Rule Medium Severity
    Show

  • Verify Group Who Owns /etc/at.allow file

    If <code>/etc/at.allow</code> exists, it must be group-owned by <code>root</code>. To properly set the group owner of <code>/etc/at.allow</code>, run the command: <pre>$ sudo chgrp root /etc/at.al...
    Rule Medium Severity
    Show

  • Verify Group Who Owns /etc/cron.allow file

    If <code>/etc/cron.allow</code> exists, it must be group-owned by <code>root</code>. To properly set the group owner of <code>/etc/cron.allow</code>, run the command: <pre>$ sudo chgrp root /etc/c...
    Rule Medium Severity
    Show

  • Verify User Who Owns /etc/at.allow file

    If <code>/etc/at.allow</code> exists, it must be owned by <code>root</code>. To properly set the owner of <code>/etc/at.allow</code>, run the command: <pre>$ sudo chown root /etc/at.allow </pre> ...
    Rule Medium Severity
    Show

  • Verify User Who Owns /etc/cron.allow file

    If <code>/etc/cron.allow</code> exists, it must be owned by <code>root</code>. To properly set the owner of <code>/etc/cron.allow</code>, run the command: <pre>$ sudo chown root /etc/cron.allow </...
    Rule Medium Severity
    Show

  • Verify Permissions on /etc/at.allow file

    If <code>/etc/at.allow</code> exists, it must have permissions <code>0640</code> or more restrictive. To properly set the permissions of <code>/etc/at.allow</code>, run the command: <pre>$ sudo c...
    Rule Medium Severity
    Show

  • Verify Permissions on /etc/cron.allow file

    If <code>/etc/cron.allow</code> exists, it must have permissions <code>0640</code> or more restrictive. To properly set the permissions of <code>/etc/cron.allow</code>, run the command: <pre>$ su...
    Rule Medium Severity
    Show

  • Deprecated services

    Some deprecated software services impact the overall system security due to their behavior (leak of confidentiality in network exchange, usage as uncontrolled communication channel, risk associated...
    Group
    Show

  • Uninstall the inet-based telnet server

    The inet-based telnet daemon should be uninstalled.
    Rule High Severity
    Show

  • Uninstall the nis package

    The support for Yellowpages should not be installed unless it is required.
    Rule Low Severity
    Show

  • Uninstall the ntpdate package

    ntpdate is a historical ntp synchronization client for unixes. It sould be uninstalled.
    Rule Low Severity
    Show

  • Uninstall the ssl compliant telnet server

    The telnet daemon, even with ssl support, should be uninstalled.
    Rule High Severity
    Show

  • Uninstall the telnet server

    The telnet daemon should be uninstalled.
    Rule High Severity
    Show

  • Configure DHCP Client if Necessary

    If DHCP must be used, then certain configuration changes can minimize the amount of information it receives and applies from the network, and thus the amount of incorrect information a rogue DHCP s...
    Group
    Show

  • Configure DHCP Server

    If the system must act as a DHCP server, the configuration information it serves should be minimized. Also, support for other protocols and DNS-updating schemes should be explicitly disabled unless...
    Group
    Show

  • Minimize Served Information

    Edit /etc/dhcp/dhcpd.conf. Examine each address range section within the file, and ensure that the following options are not defined unless there is an operational need to provide this information ...
    Rule Unknown Severity
    Show

  • DNS Server

    Most organizations have an operational need to run at least one nameserver. However, there are many common attacks involving DNS server software, and this server software should be disabled on any ...
    Group
    Show

  • Disable DNS Server

    DNS software should be disabled on any systems which does not need to be a nameserver. Note that the BIND DNS server software is not installed on Alibaba Cloud Linux 3 by default. The remainder of ...
    Group
    Show

  • Uninstall bind Package

    The named service is provided by the bind package. The bind package can be removed with the following command: 
    $ sudo yum erase bind
    Rule Low Severity
    Show

  • Application Whitelisting Daemon

    Fapolicyd (File Access Policy Daemon) implements application whitelisting to decide file access rights. Applications that are known via a reputation source are allowed access while unknown applicat...
    Group
    Show

  • fapolicyd Must be Configured to Limit Access to Users Home Folders

    fapolicyd needs be configured so that users cannot give access to their home folders to other users.
    Rule Medium Severity
    Show

  • FTP Server

    FTP is a common method for allowing remote access to files. Like telnet, the FTP protocol is unencrypted, which means that passwords and other data transmitted during the session can be captured an...
    Group
    Show

  • Configure vsftpd to Provide FTP Service if Necessary

    The primary vsftpd configuration file is /etc/vsftpd.conf, if that file exists, or /etc/vsftpd/vsftpd.conf if it does not.
    Group
    Show

  • Restrict the Set of Users Allowed to Access FTP

    This section describes how to disable non-anonymous (password-based) FTP logins, or, if it is not possible to do this entirely due to legacy applications, how to restrict insecure FTP login to only...
    Group
    Show

  • The Postfix package is installed

    A mail server is required for sending emails. The postfix package can be installed with the following command: 
    $ sudo yum install postfix
    Rule Medium Severity
    Show

  • Enable Postfix Service

    The Postfix mail transfer agent is used for local mail delivery within the system. The default configuration only listens for connections to the default SMTP port (port 25) on the loopback interfac...
    Rule Unknown Severity
    Show

  • Configure SMTP For Mail Clients

    This section discusses settings for Postfix in a submission-only e-mail configuration.
    Group
    Show

  • Postfix Network Interfaces

    The setting for inet_interfaces in /etc/postfix/main.cf
    Value
    Show

  • Postfix relayhost

    Specify the host all outbound email should be routed into.
    Value
    Show

  • Postfix Root Mail Alias

    Specify an email address (string) for a root mail alias.
    Value
    Show

  • Configure System to Forward All Mail For The Root Account

    Make sure that mails delivered to root user are forwarded to a monitored email address. Make sure that the address <xccdf-1.2:sub idref="xccdf_org.ssgproject.content_value_var_postfix_root_mail_ali...
    Rule Medium Severity
    Show

  • Configure System to Forward All Mail From Postmaster to The Root Account

    Verify the administrators are notified in the event of an audit processing failure. Check that the "/etc/aliases" file has a defined value for "root". <pre>$ sudo grep "postmaster:\s*root$" /etc/al...
    Rule Medium Severity
    Show

  • Configure System to Forward All Mail through a specific host

    Set up a relay host that will act as a gateway for all outbound email. Edit the file <code>/etc/postfix/main.cf</code> to ensure that only the following <code>relayhost</code> line appears: <pre>re...
    Rule Medium Severity
    Show

  • Disable Postfix Network Listening

    Edit the file <code>/etc/postfix/main.cf</code> to ensure that only the following <code>inet_interfaces</code> line appears: <pre>inet_interfaces = <xccdf-1.2:sub idref="xccdf_org.ssgproject.conten...
    Rule Medium Severity
    Show

  • Disable netfs if Possible

    To determine if any network filesystems handled by netfs are currently mounted on the system execute the following command: <pre>$ mount -t nfs,nfs4,smbfs,cifs,ncpfs</pre> If the command did not re...
    Group
    Show

  • NFS and RPC

    The Network File System is a popular distributed filesystem for the Unix environment, and is very widely deployed. This section discusses the circumstances under which it is possible to disable NF...
    Group
    Show

  • Disable All NFS Services if Possible

    If there is not a reason for the system to operate as either an NFS client or an NFS server, follow all instructions in this section to disable subsystems required by NFS.
    Group
    Show

  • Disable Network File Systems (netfs)

    The netfs script manages the boot-time mounting of several types of networked filesystems, of which NFS and Samba are the most common. If these filesystem types are not in use, the script can be di...
    Rule Unknown Severity
    Show

  • Disable Services Used Only by NFS

    If NFS is not needed, disable the NFS client daemons nfslock, rpcgssd, and rpcidmapd. <br> <br> All of these daemons run with elevated privileges, and many listen for network connections. I...
    Group
    Show

  • Disable rpcbind Service

    The rpcbind utility maps RPC services to the ports on which they listen. RPC processes notify rpcbind when they start, registering the ports they are listening on and the RPC program numbers they e...
    Rule Low Severity
    Show

  • 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

  • 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

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