CPENT Practice Question: Privilege Escalation Lateral Movement And Post Exploitation
An operator has gained administrative access to a Linux machine and wants to ensure persistent access that survives reboots while minimizing the chance of detection by standard security audits. Which THREE persistence methods are commonly implemented on Linux systems?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Adding a scheduled task or cron job in /etc/crontab or user crontabs to periodically execute a reverse shell
Linux persistence can be achieved via Cron jobs (scheduled tasks), modifying initialization scripts like /etc/rc.local or systemd service units, and adding SSH authorized keys to user profiles.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Adding a scheduled task or cron job in /etc/crontab or user crontabs to periodically execute a reverse shell
Why this is correct
Correct because cron jobs are widely used on Linux to execute recurring tasks and persistence payloads.
- ✓
Adding a malicious SSH public key to the target user's ~/.ssh/authorized_keys file
Why this is correct
Correct because adding an authorized SSH key allows seamless and stealthy remote shell access.
- ✗
Modifying the Windows Registry Run key using winereg
Why it's wrong here
Incorrect because registry run keys are specific to Windows operating systems, not Linux.
- ✗
Injecting shellcode into the BIOS/UEFI firmware via flashrom without user interaction
Why it's wrong here
Incorrect because BIOS/UEFI flashing requires specific hardware access and is not a standard post-exploitation persistence mechanism for routine engagements.
- ✓
Creating a custom systemd service unit file that executes a backdoor script on startup
Why this is correct
Correct because systemd services are standard on modern Linux distributions and can be configured to run persistent background tasks.
About these practice questions
This CPENT question is part of Courseiva's 274-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed August 2026 · checked against the official EC-Council exam blueprint
This CPENT practice question is part of Courseiva's free EC-Council certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the CPENT exam.