Cybersecurity PBQ Quiz

What does this command do? chmod 600 private.key

• Makes the file readable only by the owner

• Allows group and others to execute the file

• Denies access to everyone

• Grants full access to owner

What does this command do? nmap -sV 10.0.0.5

• Detect open ports

• Bypass firewalls

• Identify services and versions

• Spoof IP address

Which command blocks inbound SMTP traffic on port 25?

• iptables -A INPUT -p tcp --dport 25 -j DROP

• iptables -A OUTPUT -p tcp --dport 25 -j ACCEPT

• iptables -P INPUT DROP

• iptables -F

What does this command do? scp file.txt user@10.0.0.10:/tmp/

• Copies file from remote to local

• Sends file.txt to a remote machine via SSH

• Deletes the file after sending

• Works without SSH access

What is the effect of this command? chmod 755 script.sh

• Grants execute permission to owner, group, and others

• Gives full access to all users

• Makes the script readable, written by owner and executable by all

• See restrictive permissions denying access to others

What is the purpose of this command?

netstat -a

• Displays active listening ports

• Lists user login history

• Shows hidden processes

• Disables network traffic

What does the following command do? chown user1 file.txt

• Changes file owner to user1

• Adds user1 to the file’s access control list (ACL)

• Changes the file’s permissions to match user1’s default

• Changes permissions to 777

Which command is used to view the system hostname?

• hostname

• whoami

• uname -r

• id

What does this command do? ssh user@10.0.0.5

• Establishes a remote login session

• Sends a file via SCP

• Scans ports on the host

• Starts a web server

Which command shows the current working directory?

• pwd

• cd

• ls -la

• ls -a