OffSec PEN-103 & KLCP Certification Review
AppleTree's detailed review of the PEN-103 course and the KLCP certification exam.
OffSec PEN-103 & KLCP Certification Review
Overview
The PEN-103 / KLCP (“Kali Linux Revealed / Kali Linux Certified Professional”) is Offensive Security’s entry-level certification, but it fills a very different niche from the others in their lineup. It’s entirely about understanding and administering the Kali Linux operating system—its structure, configuration, hardening, and deployment—not penetration testing tools or attack methodology.
In short, KLCP is to Kali what RHCSA is to Red Hat: a distribution-specific administration certification designed for those who want to manage and maintain the system itself. It’s ideal for anyone building, maintaining, or securing Kali images for an offensive team, lab environment, or personal toolkit.
Like PEN-210, it’s one of the courses commonly included for free within OffSec’s Learn bundles, which makes it an accessible starting point before advancing into the more offensive courses such as PEN-200.
One thing I’ll emphasize strongly is this: do not assume that because it’s labeled a 100-level certification, it will be easy. The KLCP is extremely detail-oriented and expects you to already understand how Linux works at a low level. It’s become somewhat of an inside joke among OffSec learners that this exam can actually feel harder than some of the hands-on ones, purely because of how nuanced the technical material is. The questions assume you know how Debian behaves under the hood, and small syntax or process distinctions matter. Many capable Linux users find themselves retaking it multiple times before passing—not because they’re inexperienced, but because the test doesn’t reward surface-level familiarity.
Note: This review reflects my own experience completing the course and certification between August 24 and September 7, 2024.
Course Overview
Name & Format
- The course is called PEN-103: Kali Linux Revealed.
- It contains roughly 181 hours of content (videos, readings, and exercises) that progress from basic Linux administration to advanced Kali customization.
- It’s available free with an OffSec Learn subscription and delivered entirely through OffSec’s online training portal.
Modules Completed (2024) These were the modules included when I took the course; the structure may vary slightly today.
- Introduction
- Linux Fundamentals
- About Kali Linux
- Getting Started with Kali Linux
- Installing Kali Linux
- Configuring Kali Linux
- Helping Yourself and Getting Help
- Securing and Monitoring Kali Linux
- Debian Package Management
- Advanced Usage
- Kali Linux in the Enterprise
- Introduction to Security Assessments
- Conclusion: The Road Ahead
Course Content & Themes The content is comprehensive and builds logically from core Linux concepts to more advanced Kali administration topics. It starts with fundamentals and gradually moves into installation, networking, package management, system customization, and enterprise deployment.
What stood out to me is that it treats Kali as a full-fledged operating system to be properly configured and secured, rather than a temporary toolset for quick tests. By the end of the course, you’re comfortable installing, modifying, and maintaining Kali in the same way you would any production Linux environment. It’s an ideal starting point for those who want their Kali systems to be stable, secure, and repeatable rather than disposable.
Exam Overview (KLCP)
Format & Logistics The KLCP exam consists of 80 multiple-choice questions and lasts 90 minutes. It’s fully proctored and taken through ClassMarker, with immediate scoring when you finish. The test is completely closed-book—no notes, searches, or external materials allowed.
Difficulty & Structure The passing score is 80%, which sounds generous until you realize how technical and specific some of the questions are. The exam touches nearly every topic in the course and expects you to recall exact commands, file paths, or configuration behaviors. You can’t rely on memorization alone—you have to have worked through the material in a live Kali environment.
Many people, myself included, were surprised by just how challenging it is. This isn’t a “beginner” test in practice; it assumes familiarity with Linux fundamentals, and it’s easy to overthink questions or second-guess subtle differences in answers. It’s not uncommon for students to require multiple attempts before passing. The best preparation is hands-on work: installing Kali repeatedly, editing configurations, managing packages, and testing everything covered in the course directly.
Strengths
Completely focused on Kali Linux administration, not tools or exploitation.
Builds a deep and organized understanding of how Kali and Debian operate.
Ideal preparation for anyone maintaining Kali systems for a team or lab.
Immediate results upon submission—no waiting period for scoring.
Excellent inclusion in the OffSec Learn bundle at no additional cost.
Strong foundation for advancing to higher-level courses once your system knowledge is solid.
Limitations / Challenges
Entirely multiple-choice, so it tests knowledge more than practical skill.
Some questions are extremely subtle and easy to misread under time pressure.
A few older exercises have been replaced or simplified over time, reducing hands-on elements.
You receive no topic-level breakdown after your result, which can make it hard to pinpoint weak areas.
Although it’s an entry-level course numerically, the technical expectations are higher than many anticipate.
Comparable Courses / Certifications
| Course / Certification | Provider | Cost (2025) | Key Focus / Notes |
|---|---|---|---|
| PEN-103 / KLCP | Offensive Security | Included with OffSec Learn or $249 exam-only | Kali Linux OS administration and Debian internals |
| RHCSA (EX200) | Red Hat | $450 USD | Performance-based RHEL administration; enterprise equivalent to KLCP’s role for Kali |
| CompTIA Linux+ (XK0-005) | CompTIA | $358 USD | Vendor-neutral Linux administration fundamentals |
| LPIC-1 | Linux Professional Institute | $200 USD per exam (2 total) | General Linux administration across distributions |
| Linux Foundation LFCS | The Linux Foundation | $445 USD | Hands-on Linux sysadmin certification, distro-neutral |
Final Ratings
| Category | Rating |
|---|---|
| Knowledge Depth | ★★★★★★★★☆☆ (8 / 10) |
| Real-World Applicability | ★★★★★★☆☆☆☆ (6 / 10) |
| Value for Cost | ★★★★★★★★☆☆ (8 / 10) |
| Study Requirements | ★★★★★★★☆☆☆ (7 / 10) |
| Industry Relevance & Accessibility | ★★★★★★★★★☆ (9 / 10) |
Overall Score: 7.6 / 10
Rating Breakdown
Knowledge Depth (8/10): Covers Kali and Debian administration in strong detail for an entry-level certification.
Real-World Applicability (6/10): Focuses purely on theory and administration—useful knowledge, but the exam itself isn’t practical or task-based.
Value for Cost (8/10): Excellent value when bundled with OffSec Learn; even the standalone $249 exam option is affordable for what it offers.
Study Requirements (7/10): Requires consistent lab work and solid command-line comfort; those new to Linux will need more prep time.
Industry Relevance & Accessibility (9/10): Highly relevant for Kali users, red teams, and administrators supporting offensive operations; accessible to anyone with OffSec Learn.
Final Thoughts
PEN-103 / KLCP is a certification that rewards depth over flash. It’s not flashy, and it’s not about hacking—it’s about knowing your system so well that nothing about Kali feels like a black box. That depth pays off later, whether you’re troubleshooting, customizing images, or deploying Kali at scale.
Don’t let the “100-level” label fool you. This exam demands accuracy and understanding at a level that surprises many first-time takers. Passing requires more than following along with the online lessons—it takes real, hands-on system administration practice. In that sense, it’s one of OffSec’s most underappreciated yet technically rigorous offerings.
It’s the RHCSA of the Kali world: a focused, distro-specific credential proving you can run and manage Kali Linux properly. For anyone who lives in this ecosystem—especially red-teamers, lab builders, or sysadmins supporting offensive teams—it’s absolutely worth earning.
Note: AI-assisted editing was used to improve grammar, clarity, and formatting. All technical content and opinions are original.