What is defense evasion in cybersecurity, and which is an example technique?

• A. Techniques attackers use to avoid detection; example: obfuscated code or living-off-the-land techniques.
• B. Strategies to defeat firewalls; example: using strong encryption.
• C. Methods to improve detection by security teams; example: regular audits.
• D. A data backup strategy; example: offline storage.

Answer: (A)

Defense evasion means the techniques attackers use to slip past security controls and avoid being detected, so they can operate without raising alerts. Obfuscated code hides the true payload and behavior, making it harder for security tools to recognize malicious activity. Living-off-the-land techniques use legitimate system tools and commands to carry out actions, which can look like normal admin work and leave fewer obvious malware traces. Both strategies are classic ways to stay hidden during an intrusion, helping attackers bypass detectors and maintain access.

Other options describe defensive or protective goals—defeating a firewall, using encryption to guard data, or improving detection and backups—not the attacker-focused need to avoid detection.