LPIC-3 Security Exam Questions

LPIC-3 Security

Mounting CIFS Shares

• The uid option of mount.cifs specifies the user that appears as the local owner of the files of a mounted CIFS share when the server does not provide ownership information.

Security Practices

• Private keys should be created on the systems where they will be used and should never leave them.
• Private keys should have a sufficient length for the algorithm used for key generation.
• Private keys should not be stored as plain text files without encryption.

DNSSEC

• NSEC3 is used to prevent zone enumeration.

Access Control

• Forcing a file to be executed with the permissions of the file owner is achieved by setting the SetUID bit.
• The difference between SetUID and SetGID is that SetUID allows a file to be executed with the permissions of the file owner, while SetGID allows a file to be executed with the permissions of the group owner.

Symmetric and Asymmetric Keys

• A symmetric key is used for encryption and decryption and is the same for both.
• An asymmetric key, also known as a key pair, is used for encryption and decryption and is generated in a pair.

Linux Audit System

• The ausearch command is used to search and filter the audit log.

Network Security

• A honeypot is a network security tool designed to lure attackers into a trap.
• IP sets group together IP addresses that can be referenced by netfilter rules.

Authentication and Authorization

• rkhunter is used to detect rootkits and other security threats.

Digital Certificates

• A certificate chain is a sequence of certificates used to verify the authenticity of a digital certificate.
• A Certificate Authority (CA) issues and signs X.509 certificates.

Threats and Attacks

• A buffer overflow is a type of software vulnerability.
• A man-in-the-middle attack intercepts communications between two parties to steal information.
• A Trojan is a type of malware that disguises itself as legitimate software.
• A rogue access point is an unauthorized access point set up to look like a legitimate one.

System Hardening

• Linux Malware Detect is a tool used to detect malware on a Linux system.
• pam_cracklib is a PAM module that checks new passwords against dictionary words and enforces complexity.

DNS and DNSSEC

• RRSIG is a DNS record type used in DNSSEC.
• dnssec-keygen generates DNSSEC keys.

File Permissions and Access Control

• Linux file ownership is used to restrict access to files only to their owner.
• chmod is used to set the permissions of a file in Linux.

Network Security Tools

• iptable is used to configure firewall rules.
• nftables is used to configure packet filtering and classification.

Let me know if you'd like me to clarify or expand on any of these points!### Virtual Host and SSL

• The virtual host is used as a fallback default for all clients that do not support SNI.
• The virtual host is served only on the common name and Subject Alternative.

Apache HTTPD Configuration

• To require a client certificate for authentication, use the configuration option SSLVerifyClient require.
• SSLRequestClientCert is used to request a client certificate, but it does not require one.
• SSLVerifyClient is used to specify the verification level for client certificates.

Root CA Certificate

• A Root CA certificate is a self-signed certificate.
• It does not include the private key of the CA.
• It must contain an X509v3 Authority extension.

Host-Based Intrusion Detection (HID)

• HID is a system that monitors and detects potential security threats on a single computer or server.
• Best practice for implementing HID is to configure it to alert security personnel of potential security incidents.

SELinux Permissions

• SELinux permissions are verified after standard Linux permissions.
• SELinux permissions do not override standard Linux permissions.

Wireshark Capture Filters

• tcp portrange 10000-15000 is a valid Wireshark capture filter.

OpenVAS NVT Feed

• The command openvas-nvt-sync is used to update NVTs from the OpenVAS NVT feed.

File Permissions

• The chown command is used to set the owner and group of a file in Linux.
• The chmod command is used to set the permissions of a file in Linux.

Executable Files

• The permission bit that allows a file to be executed is Execute.

Automation of Host Scans

• Cron can be used to automate host scans on a Linux system.

sysctl Command

• The sysctl command is used to configure kernel parameters.
• The data that can be altered by the sysctl command is accessible in /proc/sys.

Access Control Lists

• The purpose of an access control list (ACL) in Linux is to specify fine-grained permissions for users and groups.

NFS Configuration

• Kerberos authentication was added to NFS in version 4.

OCSP Stapling

• OCSP stapling is a mechanism that allows a server to provide proof of the revocation status of its own SSL/TLS certificate.

FreeIPA Server

• The command ipa-server-install is used to install and configure a new FreeIPA server, including all sub-components, and creates a new FreeIPA domain.

OpenSSL Commands

• The command openssl req –new –key private/keypair.pem –out req/csr.pem is used to generate a certificate signing request (CSR) using the already existing private key contained in the file private/keypair.pem.

Cryptography

• Cryptography is the art of sending secret messages.

HID Monitoring

• HID monitors for unauthorized access attempts.

Benefits of HID

• HID provides real-time detection of security incidents.
• HID allows for quick response to security incidents.
• HID helps prevent security incidents from occurring.

Ciphertext and Plaintext

• Ciphertext is the encrypted message.
• Plaintext is the original message before encryption.

Rootkits

• A rootkit is a type of malware that disguises itself as legitimate software.

ebtables

• The command ebtables -t filter -L -v is used to display all ebtables rules contained in the table filter, including their packet and byte counters.

LDAP and Certificates

• LDAP is commonly used to transmit X.509 certificates.

Snort-stat

• The purpose of the program snort-stat is to read syslog files containing Snort information and generate port scan statistics.

chkrootkit

• chkrootkit is a tool used to check for rootkits on a Linux system.

LUKS Devices

• The command cryptsetup luksOpen /dev/sda1 crypt-vol is used to map a LUKS device.
• The command cryptsetup luksDelKey /dev/mapper/crypt-vol 1 is used to delete a key from a LUKS device.

eCryptfs

• eCryptfs is a stacked cryptographic filesystem for Linux.
• For every file in an eCryptfs directory, there exists a corresponding file that contains the encrypted content.

User Account Management

• The command chage --maxdays -1 usera is used to disable the automatic password expiry for the user usera.

TSIG and DNS

• TSIG authenticates name servers in order to perform secured zone transfers by using a secret key that is shared between the servers.

FreeIPA Components

• FreeIPA includes a Kerberos KDC, a Directory Server, and a Public Key Infrastructure.

DNSSEC

• DNSSEC is used to provide authentication of DNS data and verify the integrity of DNS data.

X.509 Certificates

• An X.509 certificate contains information such as the subject, issuer, validity dates, and public key.
• A Certificate Revocation List (CRL) is a list of X.509 certificates that have been revoked by a particular CA.

AppArmor and SELinux

• AppArmor and SELinux are both Mandatory Access Control (MAC) systems.
• AppArmor is implemented in user space only, while SELinux is a Linux kernel module.

Host Intrusion Detection

• Host intrusion detection (HID) monitors and detects potential security threats on a single computer or server.

Social Engineering

• Social engineering is a type of attack that exploits human psychology to gain access to sensitive information.

AIDE

• AIDE is a file integrity checker that detects intrusions and system changes.

DNS over TLS and DNS over HTTPS

• DNS over TLS and DNS over HTTPS are used to provide secure communication between DNS clients and servers.

LPIC-3 Security

Mounting CIFS Shares

• The uid option of mount.cifs specifies the user that appears as the local owner of the files of a mounted CIFS share when the server does not provide ownership information.

Security Practices

• Private keys should be created on the systems where they will be used and should never leave them.
• Private keys should have a sufficient length for the algorithm used for key generation.
• Private keys should not be stored as plain text files without encryption.

DNSSEC

• NSEC3 is used to prevent zone enumeration.

Access Control

• Forcing a file to be executed with the permissions of the file owner is achieved by setting the SetUID bit.
• The difference between SetUID and SetGID is that SetUID allows a file to be executed with the permissions of the file owner, while SetGID allows a file to be executed with the permissions of the group owner.

Symmetric and Asymmetric Keys

• A symmetric key is used for encryption and decryption and is the same for both.
• An asymmetric key, also known as a key pair, is used for encryption and decryption and is generated in a pair.

Linux Audit System

• The ausearch command is used to search and filter the audit log.

Network Security

• A honeypot is a network security tool designed to lure attackers into a trap.
• IP sets group together IP addresses that can be referenced by netfilter rules.

Authentication and Authorization

• rkhunter is used to detect rootkits and other security threats.

Digital Certificates

• A certificate chain is a sequence of certificates used to verify the authenticity of a digital certificate.
• A Certificate Authority (CA) issues and signs X.509 certificates.

Threats and Attacks

• A buffer overflow is a type of software vulnerability.
• A man-in-the-middle attack intercepts communications between two parties to steal information.
• A Trojan is a type of malware that disguises itself as legitimate software.
• A rogue access point is an unauthorized access point set up to look like a legitimate one.

System Hardening

• Linux Malware Detect is a tool used to detect malware on a Linux system.
• pam_cracklib is a PAM module that checks new passwords against dictionary words and enforces complexity.

DNS and DNSSEC

• RRSIG is a DNS record type used in DNSSEC.
• dnssec-keygen generates DNSSEC keys.

File Permissions and Access Control

• Linux file ownership is used to restrict access to files only to their owner.
• chmod is used to set the permissions of a file in Linux.

Network Security Tools

• iptable is used to configure firewall rules.
• nftables is used to configure packet filtering and classification.

Let me know if you'd like me to clarify or expand on any of these points!### Virtual Host and SSL

• The virtual host is used as a fallback default for all clients that do not support SNI.
• The virtual host is served only on the common name and Subject Alternative.

Apache HTTPD Configuration

• To require a client certificate for authentication, use the configuration option SSLVerifyClient require.
• SSLRequestClientCert is used to request a client certificate, but it does not require one.
• SSLVerifyClient is used to specify the verification level for client certificates.

Root CA Certificate

• A Root CA certificate is a self-signed certificate.
• It does not include the private key of the CA.
• It must contain an X509v3 Authority extension.

Host-Based Intrusion Detection (HID)

• HID is a system that monitors and detects potential security threats on a single computer or server.
• Best practice for implementing HID is to configure it to alert security personnel of potential security incidents.

SELinux Permissions

• SELinux permissions are verified after standard Linux permissions.
• SELinux permissions do not override standard Linux permissions.

Wireshark Capture Filters

• tcp portrange 10000-15000 is a valid Wireshark capture filter.

OpenVAS NVT Feed

• The command openvas-nvt-sync is used to update NVTs from the OpenVAS NVT feed.

File Permissions

• The chown command is used to set the owner and group of a file in Linux.
• The chmod command is used to set the permissions of a file in Linux.

Executable Files

• The permission bit that allows a file to be executed is Execute.

Automation of Host Scans

• Cron can be used to automate host scans on a Linux system.

sysctl Command

• The sysctl command is used to configure kernel parameters.
• The data that can be altered by the sysctl command is accessible in /proc/sys.

Access Control Lists

• The purpose of an access control list (ACL) in Linux is to specify fine-grained permissions for users and groups.

NFS Configuration

• Kerberos authentication was added to NFS in version 4.

OCSP Stapling

• OCSP stapling is a mechanism that allows a server to provide proof of the revocation status of its own SSL/TLS certificate.

FreeIPA Server

• The command ipa-server-install is used to install and configure a new FreeIPA server, including all sub-components, and creates a new FreeIPA domain.

OpenSSL Commands

• The command openssl req –new –key private/keypair.pem –out req/csr.pem is used to generate a certificate signing request (CSR) using the already existing private key contained in the file private/keypair.pem.

Cryptography

• Cryptography is the art of sending secret messages.

HID Monitoring

• HID monitors for unauthorized access attempts.

Benefits of HID

• HID provides real-time detection of security incidents.
• HID allows for quick response to security incidents.
• HID helps prevent security incidents from occurring.

Ciphertext and Plaintext

• Ciphertext is the encrypted message.
• Plaintext is the original message before encryption.

Rootkits

• A rootkit is a type of malware that disguises itself as legitimate software.

ebtables

• The command ebtables -t filter -L -v is used to display all ebtables rules contained in the table filter, including their packet and byte counters.

LDAP and Certificates

• LDAP is commonly used to transmit X.509 certificates.

Snort-stat

• The purpose of the program snort-stat is to read syslog files containing Snort information and generate port scan statistics.

chkrootkit

• chkrootkit is a tool used to check for rootkits on a Linux system.

LUKS Devices

• The command cryptsetup luksOpen /dev/sda1 crypt-vol is used to map a LUKS device.
• The command cryptsetup luksDelKey /dev/mapper/crypt-vol 1 is used to delete a key from a LUKS device.

eCryptfs

• eCryptfs is a stacked cryptographic filesystem for Linux.
• For every file in an eCryptfs directory, there exists a corresponding file that contains the encrypted content.

User Account Management

• The command chage --maxdays -1 usera is used to disable the automatic password expiry for the user usera.

TSIG and DNS

• TSIG authenticates name servers in order to perform secured zone transfers by using a secret key that is shared between the servers.

FreeIPA Components

• FreeIPA includes a Kerberos KDC, a Directory Server, and a Public Key Infrastructure.

DNSSEC

• DNSSEC is used to provide authentication of DNS data and verify the integrity of DNS data.

X.509 Certificates

• An X.509 certificate contains information such as the subject, issuer, validity dates, and public key.
• A Certificate Revocation List (CRL) is a list of X.509 certificates that have been revoked by a particular CA.

AppArmor and SELinux

• AppArmor and SELinux are both Mandatory Access Control (MAC) systems.
• AppArmor is implemented in user space only, while SELinux is a Linux kernel module.

Host Intrusion Detection

• Host intrusion detection (HID) monitors and detects potential security threats on a single computer or server.

Social Engineering

• Social engineering is a type of attack that exploits human psychology to gain access to sensitive information.

AIDE

• AIDE is a file integrity checker that detects intrusions and system changes.

DNS over TLS and DNS over HTTPS

• DNS over TLS and DNS over HTTPS are used to provide secure communication between DNS clients and servers.

LPIC-3 Security

Mounting CIFS Shares

• The uid option of mount.cifs specifies the user that appears as the local owner of the files of a mounted CIFS share when the server does not provide ownership information.

Security Practices

• Private keys should be created on the systems where they will be used and should never leave them.
• Private keys should have a sufficient length for the algorithm used for key generation.
• Private keys should not be stored as plain text files without encryption.

DNSSEC

• NSEC3 is used to prevent zone enumeration.

Access Control

• Forcing a file to be executed with the permissions of the file owner is achieved by setting the SetUID bit.
• The difference between SetUID and SetGID is that SetUID allows a file to be executed with the permissions of the file owner, while SetGID allows a file to be executed with the permissions of the group owner.

Symmetric and Asymmetric Keys

• A symmetric key is used for encryption and decryption and is the same for both.
• An asymmetric key, also known as a key pair, is used for encryption and decryption and is generated in a pair.

Linux Audit System

• The ausearch command is used to search and filter the audit log.

Network Security

• A honeypot is a network security tool designed to lure attackers into a trap.
• IP sets group together IP addresses that can be referenced by netfilter rules.

Authentication and Authorization

• rkhunter is used to detect rootkits and other security threats.

Digital Certificates

• A certificate chain is a sequence of certificates used to verify the authenticity of a digital certificate.
• A Certificate Authority (CA) issues and signs X.509 certificates.

Threats and Attacks

• A buffer overflow is a type of software vulnerability.
• A man-in-the-middle attack intercepts communications between two parties to steal information.
• A Trojan is a type of malware that disguises itself as legitimate software.
• A rogue access point is an unauthorized access point set up to look like a legitimate one.

System Hardening

• Linux Malware Detect is a tool used to detect malware on a Linux system.
• pam_cracklib is a PAM module that checks new passwords against dictionary words and enforces complexity.

DNS and DNSSEC

• RRSIG is a DNS record type used in DNSSEC.
• dnssec-keygen generates DNSSEC keys.

File Permissions and Access Control

• Linux file ownership is used to restrict access to files only to their owner.
• chmod is used to set the permissions of a file in Linux.

Network Security Tools

• iptable is used to configure firewall rules.
• nftables is used to configure packet filtering and classification.

Let me know if you'd like me to clarify or expand on any of these points!### Virtual Host and SSL

• The virtual host is used as a fallback default for all clients that do not support SNI.
• The virtual host is served only on the common name and Subject Alternative.

Apache HTTPD Configuration

• To require a client certificate for authentication, use the configuration option SSLVerifyClient require.
• SSLRequestClientCert is used to request a client certificate, but it does not require one.
• SSLVerifyClient is used to specify the verification level for client certificates.

Root CA Certificate

• A Root CA certificate is a self-signed certificate.
• It does not include the private key of the CA.
• It must contain an X509v3 Authority extension.

Host-Based Intrusion Detection (HID)

• HID is a system that monitors and detects potential security threats on a single computer or server.
• Best practice for implementing HID is to configure it to alert security personnel of potential security incidents.

SELinux Permissions

• SELinux permissions are verified after standard Linux permissions.
• SELinux permissions do not override standard Linux permissions.

Wireshark Capture Filters

• tcp portrange 10000-15000 is a valid Wireshark capture filter.

OpenVAS NVT Feed

• The command openvas-nvt-sync is used to update NVTs from the OpenVAS NVT feed.

File Permissions

• The chown command is used to set the owner and group of a file in Linux.
• The chmod command is used to set the permissions of a file in Linux.

Executable Files

• The permission bit that allows a file to be executed is Execute.

Automation of Host Scans

• Cron can be used to automate host scans on a Linux system.

sysctl Command

• The sysctl command is used to configure kernel parameters.
• The data that can be altered by the sysctl command is accessible in /proc/sys.

Access Control Lists

• The purpose of an access control list (ACL) in Linux is to specify fine-grained permissions for users and groups.

NFS Configuration

• Kerberos authentication was added to NFS in version 4.

OCSP Stapling

• OCSP stapling is a mechanism that allows a server to provide proof of the revocation status of its own SSL/TLS certificate.

FreeIPA Server

• The command ipa-server-install is used to install and configure a new FreeIPA server, including all sub-components, and creates a new FreeIPA domain.

OpenSSL Commands

• The command openssl req –new –key private/keypair.pem –out req/csr.pem is used to generate a certificate signing request (CSR) using the already existing private key contained in the file private/keypair.pem.

Cryptography

• Cryptography is the art of sending secret messages.

HID Monitoring

• HID monitors for unauthorized access attempts.

Benefits of HID

• HID provides real-time detection of security incidents.
• HID allows for quick response to security incidents.
• HID helps prevent security incidents from occurring.

Ciphertext and Plaintext

• Ciphertext is the encrypted message.
• Plaintext is the original message before encryption.

Rootkits

• A rootkit is a type of malware that disguises itself as legitimate software.

ebtables

• The command ebtables -t filter -L -v is used to display all ebtables rules contained in the table filter, including their packet and byte counters.

LDAP and Certificates

• LDAP is commonly used to transmit X.509 certificates.

Snort-stat

• The purpose of the program snort-stat is to read syslog files containing Snort information and generate port scan statistics.

chkrootkit

• chkrootkit is a tool used to check for rootkits on a Linux system.

LUKS Devices

• The command cryptsetup luksOpen /dev/sda1 crypt-vol is used to map a LUKS device.
• The command cryptsetup luksDelKey /dev/mapper/crypt-vol 1 is used to delete a key from a LUKS device.

eCryptfs

• eCryptfs is a stacked cryptographic filesystem for Linux.
• For every file in an eCryptfs directory, there exists a corresponding file that contains the encrypted content.

User Account Management

• The command chage --maxdays -1 usera is used to disable the automatic password expiry for the user usera.

TSIG and DNS

• TSIG authenticates name servers in order to perform secured zone transfers by using a secret key that is shared between the servers.

FreeIPA Components

• FreeIPA includes a Kerberos KDC, a Directory Server, and a Public Key Infrastructure.

DNSSEC

• DNSSEC is used to provide authentication of DNS data and verify the integrity of DNS data.

X.509 Certificates

• An X.509 certificate contains information such as the subject, issuer, validity dates, and public key.
• A Certificate Revocation List (CRL) is a list of X.509 certificates that have been revoked by a particular CA.

AppArmor and SELinux

• AppArmor and SELinux are both Mandatory Access Control (MAC) systems.
• AppArmor is implemented in user space only, while SELinux is a Linux kernel module.

Host Intrusion Detection

• Host intrusion detection (HID) monitors and detects potential security threats on a single computer or server.

Social Engineering

• Social engineering is a type of attack that exploits human psychology to gain access to sensitive information.

AIDE

• AIDE is a file integrity checker that detects intrusions and system changes.

DNS over TLS and DNS over HTTPS

• DNS over TLS and DNS over HTTPS are used to provide secure communication between DNS clients and servers.

Network Monitoring

• It monitors remote hosts by periodically sending echo requests to them.

Asymmetric Keys

• An asymmetric key is a key used for both encryption and decryption that is generated in a pair.

HID Techniques

• Anomaly-based detection is a behavioral-based HID technique.

File Permissions

• The command setfacl is used to set access control lists (ACLs) on files.
• The command setfattr is used to set extended attributes on files.
• The command getfacl is used to view the access control list of a file.

DNS

• The PTR record is used to map an IP address to a hostname.
• The DNSKEY record is used to sign a DNS zone in DNSSEC.

Security

• Phishing is a type of social engineering attack.
• Social engineering is a type of attack that aims to deceive individuals into divulging sensitive information.

Access Control

• Mandatory Access Control (MAC) is an access control model established by using SELinux.

VPNs

• The --mlock option of the openvpn command is used to ensure that ephemeral keys are not written to the swap space.

Linux File Attributes

• Linux Extended File Attributes are organized in namespaces, including system, trusted, and user.

Nmap Scan Techniques

• Existing scan techniques with nmap include Xmas Scan and FIN Scan.

User Management

• The ipa user-add command is used to add a new user to FreeIPA.

Security Threats

• A man-in-the-middle attack is an attack that intercepts communications between two parties to steal information.
• A Certificate Revocation List (CRL) is a list of X.509 certificates that have been revoked by a particular CA.
• Host intrusion detection (HID) is a system that monitors and detects potential security threats on a single computer or server.
• AIDE is used to detect intrusions and system changes.

Network Monitoring

• It monitors remote hosts by periodically sending echo requests to them.

Asymmetric Keys

• An asymmetric key is a key used for both encryption and decryption that is generated in a pair.

HID Techniques

• Anomaly-based detection is a behavioral-based HID technique.

File Permissions

• The command setfacl is used to set access control lists (ACLs) on files.
• The command setfattr is used to set extended attributes on files.
• The command getfacl is used to view the access control list of a file.

DNS

• The PTR record is used to map an IP address to a hostname.
• The DNSKEY record is used to sign a DNS zone in DNSSEC.

Security

• Phishing is a type of social engineering attack.
• Social engineering is a type of attack that aims to deceive individuals into divulging sensitive information.

Access Control

• Mandatory Access Control (MAC) is an access control model established by using SELinux.

VPNs

• The --mlock option of the openvpn command is used to ensure that ephemeral keys are not written to the swap space.

Linux File Attributes

• Linux Extended File Attributes are organized in namespaces, including system, trusted, and user.

Nmap Scan Techniques

• Existing scan techniques with nmap include Xmas Scan and FIN Scan.

User Management

• The ipa user-add command is used to add a new user to FreeIPA.

Security Threats

• A man-in-the-middle attack is an attack that intercepts communications between two parties to steal information.
• A Certificate Revocation List (CRL) is a list of X.509 certificates that have been revoked by a particular CA.
• Host intrusion detection (HID) is a system that monitors and detects potential security threats on a single computer or server.
• AIDE is used to detect intrusions and system changes.

Network Monitoring

• It monitors remote hosts by periodically sending echo requests to them.

Asymmetric Keys

• An asymmetric key is a key used for both encryption and decryption that is generated in a pair.

HID Techniques

• Anomaly-based detection is a behavioral-based HID technique.

File Permissions

• The command setfacl is used to set access control lists (ACLs) on files.
• The command setfattr is used to set extended attributes on files.
• The command getfacl is used to view the access control list of a file.

DNS

• The PTR record is used to map an IP address to a hostname.
• The DNSKEY record is used to sign a DNS zone in DNSSEC.

Security

• Phishing is a type of social engineering attack.
• Social engineering is a type of attack that aims to deceive individuals into divulging sensitive information.

Access Control

• Mandatory Access Control (MAC) is an access control model established by using SELinux.

VPNs

• The --mlock option of the openvpn command is used to ensure that ephemeral keys are not written to the swap space.

Linux File Attributes

• Linux Extended File Attributes are organized in namespaces, including system, trusted, and user.

Nmap Scan Techniques

• Existing scan techniques with nmap include Xmas Scan and FIN Scan.

User Management

• The ipa user-add command is used to add a new user to FreeIPA.

Security Threats

• A man-in-the-middle attack is an attack that intercepts communications between two parties to steal information.
• A Certificate Revocation List (CRL) is a list of X.509 certificates that have been revoked by a particular CA.
• Host intrusion detection (HID) is a system that monitors and detects potential security threats on a single computer or server.
• AIDE is used to detect intrusions and system changes.

Practice questions for the LPIC-3 Security certification exam, covering various security topics and Linux system administration.