Linux Security Quiz | CyberSec Academy

1. What is the minimum secure permission for /etc/shadow?

640

644

600

660

2. Which command shows SUID binaries?

find / -perm -4000

ls -l /bin/*

chmod +s /bin/ls

stat -c "%a %n" /bin/*

3. What is the purpose of SELinux?

Mandatory access control

Disk encryption

Network firewall

Package management

4. Which file controls password aging policies?

/etc/login.defs

/etc/passwd

/etc/security

/etc/shadow

5. What does chattr +i do to a file?

Makes it immutable

Encrypts the file

Changes ownership

Sets SUID bit

6. Which tool checks for common Linux vulnerabilities?

Lynis

Nmap

Wireshark

Metasploit

7. What is the secure alternative to telnet?

SSH

FTP

Rlogin

Netcat

8. Which file should be empty for secure systems?

/etc/securetty

/etc/hosts.deny

/etc/fstab

/etc/resolv.conf

9. What does umask 027 mean?

Files: 640, Directories: 750

Files: 644, Directories: 755

Files: 600, Directories: 700

Files: 777, Directories: 777

10. Which command securely removes a file?

shred -u

rm -f

del /s

unlink