public/subjects/devops/deep-in-system/audit

General

Check the Repo content

Files that must be inside the repository:

• DeepInSystem.sha1

Are the required files present?

Verify that the virtual machine that will be audited is the one that is submitted:

user:~$ sha1sum deep-in-system.ova > deep-in-system-toaudit.sha1
user:~$ diff deep-in-system.sha1  deep-in-system-toaudit.sha1 ; echo $?
0
user:~$

Is the SHA1 of the provided machine the same as the machine being audited?

Check the Virtual machine aliases

The virtual machine is clean of any alias that may affect the results of the audit commands?

The Virtual Machine Part:

Check the Linux distribution

To get information about the OS release:

user:~$ cat /etc/os-release
PRETTY_NAME="Ubuntu <...> LTS"
NAME="Ubuntu"
VERSION_ID="<...>"
VERSION="<...> LTS <...>"
VERSION_CODENAME=<...>
ID=ubuntu
ID_LIKE=debian
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
UBUNTU_CODENAME=<...>
user:~$

Check if ubuntu is a server and not a desktop:

user:~$ dpkg -l ubuntu-desktop
dpkg-query: no packages found matching ubuntu-desktop
user:~$

You can check the versions of the ubuntu server from here: Get Ubuntu Server

Is the installed Linux distribution is Ubuntu server's latest LTS?

Check the VM disk and partitions

Check the VM disk and partitions with this command:

user:~$ lsblk -o NAME,FSTYPE,SIZE,MOUNTPOINT /dev/sda
NAME   FSTYPE SIZE MOUNTPOINT
sda            30G
├─sda<...>          1M
├─sda<...> swap     4G [SWAP]
├─sda<...> ext4    15G /
├─sda<...> ext4     5G /home
└─sda<...> ext4     6G /backup
user:~$

• The VM disk size must be 30GB.

• VM disk must be divided into these partitions: "swap:" 4G "/": 15G "/home": 5G "/backup": 6G

Is the VM Disk size correct?

There is no problem if the size of the divisions is not very accurate (Authorized error rate: <= 0.5G)!

Are the VM disk partitions correct?

Check the hostname and user name

To check the hostname:

user:~$ hostname
<username>-host
user:~$

To check the user name and groups:

user:~$ id
uid=<...>({username}) gid=<...>({username}) groups=<...>({username}),<...>(sudo),<...>
user:~$

Does the hostname in the format of "{username}-host"?

Does the student use a user different from the "root" user?

Does the username contain the student login?

Does the user in the sudo group?

Does the student can explain what is sudo group in Linux?

The Network & Security Part:

Check the VM IP address

The student must show the file that was modified to set a static IP address.

Does the student can explain the configuration?

Does the student What is a netmask?

Check if the IP address is static with this command:

user:~$ ip a | grep dynamic
user:~$

There is no internet interface with dynamic IP assignment?

Check if the internet works fine with the static IP address:

user:~$ ping -c 5 google.com

Can connect to the internet properly?

Can The student explain why a static IP address is important for a web server?

Check the sshd configuration

The student must show the file that was modified to secure the ssh server.

Does the student can explain the configuration?

Is the root access disabled in the sshd config (PermitRootLogin: no)?

Is the port of the sshd "2222"?

Try to connect from outside the VM

outsideTheVM:~$ ssh {username}@{machine-ip} -p 2222
{username}@{machine-ip}'s password:
Welcome to Ubuntu <......>
InsideTheVM:~$ hostname
{username}-host
InsideTheVM:~$

Can connect to the ssh properly?

Does the student can explain what is ssh server and what the role of it?

Check the firewall

If the student uses ufw you can check it with this command:

user:~$ sudo ufw status
Status: active

To                         Action      From
--                         ------      ----
2222/tcp                   ALLOW       Anywhere
<...>
Apache                     ALLOW       Anywhere
<...>
user:~$

Otherwise, the student must show what firewall is used.

Is the firewall activated?

Ask the student to justify why each open port is open

Are all open ports justified?

Is the MySQL port not open in the firewall?

Does the student can explain what is firewall and what the role of it in a server?

User Management Part:

Check luffy user

The student should connect to the machine with the "luffy" user by using this ssh key:

• Private key: The student's generated ssh key

Is the student able to connect to the machine with the "luffy" user by using the private key and without using any password?

Check the groups of luffy user:

luffy:~$ groups luffy
luffy : luffy sudo
luffy:~$

Check the home directory of luffy user:

luffy:~$ echo ~
/home/luffy
luffy:~$ echo $HOME
/home/luffy
luffy:~$

Is the "luffy" user assigned to the sudo group?

Is the home directory of "lufy" user: /home/luffy?

Check zoro user

The student should connect to the machine with the "zoro" user by using a password.

Is the student able to connect to the machine with the "zoro" user by a password?

Try to execute a command with sudo:

zoro:$ sudo cat /etc/shadow
zoro is not in the sudoers file.  This incident will be reported.
zoro:~$

Check the groups of zoro user:

zoro:~$ groups zoro
zoro : zoro
zoro:~$

Check the home directory of zoro user:

zoro:~$ echo ~
/home/zoro
zoro:~$ echo $HOME
/home/zoro
zoro:~$

Is the "zoro" user can't perform a command with sudo?

Is the "zoro" user not assigned to the sudo group?

Is the home directory of "zoro" user: /home/zoro?

Ask the student to:

In less than 10 minutes the student must create a user called "kratos" this user must be a sudoer and must be able to connect with a private key. The private ssh key must be created by the student during this exam. After the student finishes creating and setting up the user, the student must show that the user can be connected with the private key and can perform a sudo command.

If the student can't solve this exam, he must directly fail in this project. If did not pass this exam and was able to succeed in this project, a temporal crater will open and the world will be destroyed!

Does the student can create a private key?

Does the student can create the user?

Does the student assign the public key to the user?

Does the student add the user to the sudo group?

Is user "kratos" can connect with the private key?

Is user "kratos" can perform a sudo command?

Services Part:

Check nami user:

By using SSH create a file inside /backup:

$ sudo touch /backup/audit-check

Try to connect to the "nami" user via FTP:

user:~$ ftp {vm-ip}
Connected to {vm-ip}.
<...>
Name ({vm-ip}:{username}): nami
331 Please specify the password.
Password:
230 Login successful.
Remote system type is UNIX.
Using binary mode to transfer files.
ftp> ls
<...>
<...> audit-check
<...>
226 Directory send OK.
ftp> get audit-check
<...>
226 Transfer complete.
ftp>

Can connect with user "nami" and a password to the FTP Server properly?

Is the created file exist in the FTP Server?

Can get the audit-check file from the FTP Server?

Check anonymous user:

Try to connect with an anonymous user and a blank password:

user:~$ ftp {vm-ip}
Connected to {vm-ip}.
<...>
Name ({vm-ip}:{username}): anonymous
331 Please specify the password.
Password:
530 Login incorrect.
ftp: Login failed
ftp>

Can't connect to FTP Server with an anonymous user and blank password?

Does the student can explain what is FTP Server and what the role of it?

WordPress Part:

From your browser, enter "http://{vm-ip}/"

it can be https instead of http if the student installs an SSL certificate!

Ask the student to log in with the admin user.

WordPress must be installed.

Try to post something, any way you are free to do anything.

Is WordPress installed and working properly?

Try to access to "http://{vm-ip}/wp-config.php"

The WordPress config file content is not displayed?

Backup Part:

Check the cronjob:

The student must show created cronjob.

Is they are a cron job that starts every Day At 00:00 (0 0 * * *)?

Is the cronjob command creating a tar file of the WordPress database in /backup?

Check the FTP system functionality:

Before starting this test you have to remove all WordPress backup files in "/backup" and delete the logs file "/var/log/backup.log".

In the crontab, you have to change the scheduling to :

* * * * *

After 1 minute, check the FTP Server with the "nami" user:

user:~$ ftp {vm-ip}
Connected to {vm-ip}.
<...>
Name ({vm-ip}:{username}): nami
331 Please specify the password.
Password:
230 Login successful.
Remote system type is UNIX.
Using binary mode to transfer files.
ftp> ls
<...>
<...> {wordpress-backupfile}
<...>
226 Directory send OK.
ftp> get audit-check
<...>
226 Transfer complete.
ftp>

Does a WordPress database backup file with the date of today exists in the FTP Server?

Check the backup logs file:

user:~$ cat /var/log/backup.log
<...>wordpress backup created!, date: <...>
user:~$

Is the backup logs file existing and contains a message informing you that the backup was successful and the timing of the backup?

Does the student can explain what is cronjob and what the role of it?

Does the student can explain why backup is important?

Bonus

+ Did the student pass the account creation exam without error and in a short time?

+ Did the student add any optional bonus?

+ Is the student a genius of the system administration?