How To Pass The Osep Exam On Your First Attempt: The 90-day Pen-300 Blueprint

By Author: Passyourcert
Total Articles: 471
Comment this article

The osep certification (Offensive Security Experienced Penetration Tester), awarded via OffSec’s PEN-300 course, is an advanced cybersecurity credential focused on enterprise defense evasion and Active Directory exploitation. This practical osep cert validates skills in bypassing antivirus/EDR, custom payload development, and post-exploitation tradecraft. Costing $1,749 for a 90-day lab bundle, candidates must pass a rigorous 48-hour proctored hands-on exam (47 hours and 45 minutes of live hacking plus 24 hours for report writing) by scoring 70 points or compromising the final domain objective.
What Is the OffSec OSEP Certification?
The osep offensive security designation—officially titled ... data-path-to-node="4" data-index-in-node="58">Evasion Techniques and Breaching Defenses (PEN-300)—is OffSec’s flagship advanced penetration testing course. While foundational certifications like the OSCP evaluate a practitioner's ability to discover unpatched vulnerabilities and execute known exploits, the osep certification tests your capacity to breach hardened enterprise networks protected by modern security stacks.
Modern Endpoint Detection and Response (EDR) platforms, Antivirus (AV) engines, and SOC monitoring render off-the-shelf public exploits useless in mature environments. The PEN-300 curriculum forces operators to abandon automated frameworks and build custom offensive tradecraft from scratch.
Key Capabilities Tested in PEN-300

Client-Side Weaponization: Crafting malicious Office macros, HTA files, and JScript payloads that execute in memory without writing flagged artifacts to disk.

AV and EDR Evasion: Bypassing signature-based and behavioral detection using custom C# shellcode runners, dynamic API resolving, and process injection techniques (e.g., Process Hollowing, Thread Execution Hijacking).

Bypassing In-Memory Protections: Patching Antimalware Scan Interface (AMSI) and Event Tracing for Windows (ETW) directly in process memory prior to executing offensive assemblies.

Advanced Active Directory Exploitation: Executing complex AD attack chains including Kerberoasting, Unconstrained Delegation, Constrained Delegation, Resource-Based Constrained Delegation (RBCD), and cross-forest trust abuses.

Linux and Network Evasion: Bypassing Linux defensive controls, exploiting application logic, and establishing persistent encrypted tunnels across segmented network boundaries.

Acronym Clarification: OSEP Certification vs. Educational OSEP Entities
When researching osep online, search engine results frequently combine two completely distinct entities sharing the same acronym.
While the U.S. osep department of education oversees the office of special education programs osep—which funds federal initiatives such as the osep technical assistance center, osep special education resources, broader osep education policies, and the osep technical assistance center on positive behavioral interventions & supports hosted across their official osep web domain—offensive cybersecurity professionals operate in a completely separate technical domain.
In information security, osep refers exclusively to the Offensive Security Experienced Penetration Tester certification. If your objective is enterprise red teaming, EDR evasion, and advanced pentesting, this guide focuses entirely on passing the technical osep cert.
OffSec PEN-300 & OSEP Exam Cost Structure
Understanding the total financial investment for the osep cert is critical for both independent learners and enterprise training budgets. OffSec offers several enrollment tiers for the PEN-300 course:

Option / Package
Cost (USD)
Lab Access Duration
Exam Attempts Included
Ideal Candidate Profile

PEN-300 Course + Cert Bundle
$1,749
90 Days
1 Attempt
Standard candidates dedicating 15–20 hours/week to study.

Learn One Subscription
$2,749 / year
365 Days
2 Attempts
Learners needing extended lab time or preparing for multiple certs.

Learn Unlimited Subscription
$6,099 / year
365 Days
Unlimited Attempts
Enterprise security teams pursuing multiple OffSec certifications.

OSEP Exam Retake Voucher
$249
N/A
1 Attempt
Candidates who need a second attempt after exhausting bundled vouchers.

Note: The osep exam cost includes access to over 670 hours of course content, 20+ hands-on modules, and 7 realistic Challenge Labs that simulate complex corporate target environments.
OSCP vs. OSEP Certification: The Technical Chasm
Many candidates assume OSEP is simply "OSCP with more machines." That assumption leads directly to exam failure. Below is a direct comparison of the technical expectations between the two credentials:

Domain
OSCP (PEN-200)
OSEP (PEN-300)

Primary Objective
Identify and exploit known vulnerabilities.
Bypass active security controls and operate undetected.

Payload Execution
Standard C2 payloads (msfvenom).
Custom C# payload wrappers, XOR/AES obfuscation, dynamic P/Invoke.

PowerShell Usage
Native powershell.exe execution.
Unmanaged PowerShell, reflection, in-memory script execution.

Defensive Controls
Standard target environments (No AV/EDR).
Active Windows Defender, AMSI, ETW, and EDR hooks.

Active Directory
Basic enumeration, BloodHound, Pass-the-Hash.
Multi-forest trusts, RBCD, MSSQL link chains, shadow credentials.

Exam Duration
23h 45m Exam / 24h Report
47h 45m Exam / 24h Report

The 90-Day PEN-300 Blueprint
Passing the osep certification requires a structured, discipline-driven study strategy. This 90-day blueprint is designed to take an OSCP-level practitioner to OSEP readiness.

+-----------------------------------------------------------------------------------+
| THE 90-DAY PEN-300 ROADMAP |
+-----------------------------------------------------------------------------------+
| MONTH 1: Weaponization & Evasion --> C#, Win32 API, AMSI/ETW Patching, Process |
| Injection & Obfuscation Frameworks |
+-----------------------------------------------------------------------------------+
| MONTH 2: Advanced AD & Tunnels --> RBCD, Kerberos Delegation, MSSQL Links, |
| Double-Hop Fixes, Multi-Forest Exploits |
+-----------------------------------------------------------------------------------+
| MONTH 3: Challenge Labs & Exam --> Clear Labs 1-7, Automate C# Shellcode |
| Runners, Execute 48-Hour Exam Simulation |
+-----------------------------------------------------------------------------------+

Phase 1: Days 1–30 — Weaponization, Shellcode, and In-Memory Evasion
The first month must be dedicated to mastering custom client-side delivery and AV/EDR evasion.

Master C# and Win32 API Interop:
Learn how C# interacts with unmanaged code via P/Invoke. Practice calling core Windows APIs directly:

VirtualAlloc (allocating executable memory)

Marshal.Copy (writing shellcode to memory)

CreateThread / RtlMoveMemory (executing payloads in current or remote processes)

Implement AMSI and ETW Bypasses:
Understand how the Antimalware Scan Interface inspects memory. Practice patching AmsiScanBuffer in memory using VirtualProtect to overwrite scan instructions before executing custom assemblies. Similarly, patch EtwEventWrite to blind telemetry sent to EDR loggers.

Process Injection Techniques:
Build functional C# tools for Process Hollowing (spawning svchost.exe or explorer.exe in a suspended state, unmapping original memory, writing custom shellcode, and resuming execution).

Phase 2: Days 31–60 — Lateral Movement, SQL Crawling, and Advanced Active Directory
The second month shifts focus from endpoint evasion to domain takeover across complex enterprise topologies.

Unmanaged PowerShell Execution:
Because powershell.exe logs heavily via Script Block Logging and AMSI, master running PowerShell code through unmanaged C# executables (using System.Management.Automation.dll) or tools like PowerPick.

MSSQL Server Exploitation Chains:
Practice link crawling across database networks. Learn how to execute code via xp_cmdshell, escalate privileges using impersonation tokens, and traverse nested SQL links across domain boundaries.

Kerberos Delegation & RBCD:

Unconstrained Delegation: Extracting TGTs from memory using Mimikatz.

Constrained Delegation: Forging TGT/S4U2proxy requests to compromise target services.

Resource-Based Constrained Delegation (RBCD): Exploiting write permissions on computer objects (msDS-AllowedToActOnBehalfOfOtherIdentity) to take over domain controllers.

Phase 3: Days 61–90 — OffSec Challenge Labs & Exam Simulation
The final month is dedicated to hands-on consolidation inside OffSec’s lab environment.

Conquer Challenge Labs 1 through 7:
The PEN-300 course features 7 standalone Challenge Labs. Challenge 1 through 6 cover specific concepts (Kiosk breakouts, Linux lateral movement, MSSQL pivoting). Challenge 7 is a full-scale corporate network simulation that mirrors the actual exam layout.

Build Your Automated C# Template Library:
Do not spend exam time writing C# boilerplates from scratch. Pre-build obfuscated templates for:

AES/XOR Encrypted Shellcode Runners

AMSI / ETW In-Memory Patchers

Process Hollowing and DLL Injection Executables

Reverse Port Forwarders and Chisel Proxy Wrappers

Mastering the 48-Hour OSEP Exam Strategy
The osep certification exam is a true test of technical endurance, operational pacing, and documentation discipline.
Exam Format & Rules

Duration: 47 hours and 45 minutes of active network access, followed by 24 hours to write and submit a formal penetration testing report.

Proctoring: The entire practical exam is proctored via screen-sharing and webcam streams through OffSec’s secure VPN client.

Passing Score: 70 points out of 100 OR finding the designated secret.txt file located on the primary domain objective.

Tool Restrictions:

Prohibited: Commercial C2 frameworks (Cobalt Strike, Metasploit Pro, Burp Suite Pro) and AI LLMs/Chatbots (e.g., ChatGPT, Gemini).

Allowed: Open-source C2s (Covenant, Empire), Metasploit Framework (community edition), BloodHound, Chisel, and custom compiled binaries.

Tactical Pacing for the 48-Hour Exam Shift

+-----------------------------------------------------------------------------------+
| 48-HOUR EXAM PACING & SLEEP SCHEDULE |
+-----------------------------------------------------------------------------------+
| HOURS 00 - 12 : Initial Foothold & First EDR Bypass |
| Establish external entry point, bypass Defender, gain local.txt. |
+-----------------------------------------------------------------------------------+
| HOURS 12 - 14 : MANDATORY REST (2-Hour Sleep & Mental Reset) |
+-----------------------------------------------------------------------------------+
| HOURS 14 - 28 : Internal Enumeration & MSSQL / AD Escalation |
| Enumerate domain trusts, execute RBCD/Delegation attacks. |
+-----------------------------------------------------------------------------------+
| HOURS 28 - 34 : MANDATORY SLEEP (6-Hour Complete Rest) |
+-----------------------------------------------------------------------------------+
| HOURS 34 - 47 : Final Network Pivoting & Target Compromise (`secret.txt`) |
| Consolidate proof screenshots with full IP/hostname context. |
+-----------------------------------------------------------------------------------+

Essential Exam Tips

Take Screenshots Immediately: Every flag submission (local.txt, proof.txt, or secret.txt) requires an explicit screenshot showing the file contents, target IP address (ipconfig / ifconfig / ip addr), and active shell context. Missing a screenshot results in zero points for that machine.

Document Custom Code: OffSec requires exact source code listings in your final report for any custom exploits, modified payload runners, or bypass scripts used during exploitation.

Accelerate Your Exam Preparation
Earning your osep certification places you in the upper echelon of offensive security professionals, opening direct pathways into senior red team, principal pentesting, and specialized threat emulation roles. By focusing on payload obfuscation, Win32 API interactions, and deep Active Directory delegation exploits during your 90-day blueprint, you maximize your ability to breach hardened target networks and pass on your first attempt.

PassYourCert is a leading provider of security and technology training and consulting services, specialising in a wide range of IT security courses and information security services. PassYourCert was founded by a group of dedicated and experienced experts with over 15 years of expertise in the field. If you are looking for Professional training, certification, and consulting services in all areas of information technology and cyber security, Visit: https://passyourcert.net/ and contact us