Lab Activity
Module 10: Security
Learn to secure Linux systems through file permissions, special bits, encryption, and integrity verification to strengthen overall system security.
Overview
In this lab, you'll explore key Linux security concepts and practical techniques for hardening systems. You'll learn how to manage file permissions, secure user access, apply special permission bits (SUID, SGID, Sticky), and verify file integrity using checksum and encryption tools. The lab also walks through detecting security risks, enforcing access control, and performing integrity checks to ensure a secure operating environment.
Learning Outcomes
- Understand Linux user security, permissions, and access control mechanisms.
- Learn to apply file permission restrictions to secure sensitive data.
- Explore and configure special permission bits (SUID, SGID, Sticky).
- Implement file integrity checks using hashing algorithms like SHA256.
- Perform encryption and decryption with GPG for secure data handling.
- Identify potential security vulnerabilities in user accounts and file systems.
Key Concepts
- File Permissions & Ownership: Control read, write, and execute rights to maintain data confidentiality and integrity.
- SUID, SGID, and Sticky Bit: Special permission bits that modify execution and access behavior for files and directories.
- Checksum & Integrity Verification: Detect file tampering using SHA256 hash comparisons.
- GPG Encryption: Secure data through symmetric encryption and controlled access.
- User Access Management: Evaluate user privileges and monitor login attempts for unauthorized access.
- Umask & Default Permissions: Manage secure defaults for newly created files.
Why It Matters
- Prevents unauthorized access and privilege escalation.
- Reduces security risks by enforcing least-privilege principles.
- Protects sensitive data through encryption and controlled file access.
- Strengthens system integrity with automated verification methods.
- Builds a foundational understanding of Linux security practices for professional system administration.