Penetration Tester & Security Consultant
James Lenkiewicz
10+ years of experience conducting enterprise network and security assessments.
Former US Coast Guard cyber operator.
OSCP certified.
Founder of ChainLenk LLC.
About me
I'm a penetration tester and offensive security professional with over a decade of experience across enterprise networks, Active Directory environments, web applications, and maritime critical infrastructure. My background spans the US Coast Guard's cyber protection teams, intelligence operations, and SOC leadership.
I founded ChainLenk LLC to bring that same level of rigorous, manual security testing to organizations that need more than automated scans. Every engagement I run is thorough, documented, and mapped to real-world impact — not just a list of CVEs.
Work Experience
Founder & Principal Penetration Tester
ChainLenk LLC
February 2026 - Present
Independent security consulting practice specializing in penetration testing across web applications, Active Directory, and network infrastructure. Delivering manual, impact-driven assessments with professional reporting mapped to MITRE ATT&CK and NIST frameworks.
Senior Enlisted Leader
Cybersecurity Operations Center, US Coast Guard — Washington, D.C.
2025 - Present
Led cyber operations center with 50+ personnel overseeing 24/7 network defense, incident response, and threat hunting across the US Coast Guard enterprise. Advised senior leadership on cyber threats and defensive posture, translating technical risk into operational decisions supporting national security and DHS cyber objectives.
Mission Element Crew Lead
US Coast Guard Cyber Protection Team
2021 - 2025
Led network and wireless penetration tests across maritime systems. Conducted enterprise assessments with Burp Suite and Nessus, identifying critical misconfigurations and exploitable flaws. Delivered technical reports mapping vulnerabilities to MITRE and NIST frameworks. Trained team members on exploitation techniques, increasing team capability and reducing external support needs.
Intelligence Specialist
US Coast Guard Intelligence Branch, District 17
2019 - 2021
Generated daily AOR intelligence reports informing leadership of emerging maritime threats. Developed CHAINLENK, a Python tool that optimized enforcement against IUU fishing and supported Operation North Pacific Guard — directly enabling identification of 14 violations on foreign-flagged vessels.
Certifications
Offensive Security Certified Professional (OSCP)
Offensive Security
Certified Active Directory Penetration Testing Expert (CAPE)
Hack The Box
GIAC Red Team Professional (GRTP)
GIAC
GIAC Penetration Tester (GPEN)
GIAC
GIAC Certified Incident Handler (GCIH)
GIAC
GIAC Certified Forensic Examiner (GCFE)
GIAC
Security+ & Network+
CompTIA
Technical Skills
A decade of hands-on offensive security experience across diverse environments and technologies.
Web Application Testing
Burp Suite, OWASP Top 10, authentication bypass, injection flaws, business logic vulnerabilities.
Active Directory Attacks
Kerberoasting, AS-REP roasting, delegation abuse, lateral movement, domain compromise.
Network Penetration Testing
External and internal assessments, wireless testing, network segmentation bypass.
Vulnerability Research
Zero-day class vulnerability discovery, chained exploit development, logic flaw identification.
MITRE ATT&CK & NIST
Mapping findings to frameworks for risk-driven remediation and executive reporting.
Red Team Operations
Multi-phase engagements, evasion techniques, realistic adversary simulation.
Need a Penetration Test?
Get in touch to discuss your security assessment needs. Manual, thorough, and professionally delivered.