Cyber Security Engineer – Penetration Tester (Journeyman)

OneZero Solutions is hiring a Journeyman-level Cyber Security Engineer focused on penetration testing and adversary emulation in a hybrid role based in Washington, DC, supporting the U.S. Coast Guard in Alexandria, VA. You will help strengthen operational cyber defenses through hands-on offensive testing, threat emulation, and clear reporting that drives actionable recommendations.

What you will do

• Assess the cyber security posture of Coast Guard operational networks through adversary emulation.
• Conduct red team operations, internal and external penetration testing, and phishing assessments.
• Perform cyber threat emulation during scripted exercises to train DoD Cyber Protection Teams.
• Deploy, configure, and operate Command and Control (C2) frameworks such as Cobalt Strike, Havoc, Mythic, and Sliver.
• Apply TTPs for initial access, lateral movement, privilege escalation, persistence, and data exfiltration.
• Leverage proprietary and open-source offensive security tool sets to achieve engagement objectives.
• Monitor, manage, and maintain cloud and on-premise infrastructure used during assessments.
• Use Git repositories to maintain operational tools and scripts.
• Perform network mapping and enumeration, including Active Directory attack path analysis using tools such as BloodHound.
• Assess web and mobile applications and perform database scans.
• Develop reports and briefs that document findings and recommendations for completed assessments.

Clearance and security requirements

• Maintain an active Top Secret security clearance with SCI eligibility.

Required skills and experience

• 2 to 3 years of relevant experience (or a Bachelor’s degree in BA/BS or equivalent years of relevant experience).
• Hands-on experience with computers and network security.
• Experience conducting phishing campaigns or social engineering.
• Hands-on experience with red team tasks and penetration testing.
• Familiarity with malware development and EDR/AV bypass strategies.
• Experience with PowerShell, C, C++, or Python.
• Hands-on experience using C2 frameworks such as Cobalt Strike, Sliver, Havoc, or similar.

Benefits and support

• Health insurance
• Dental insurance
• Vision insurance
• Life insurance
• 401(k) with company matching
• Paid time off and holidays
• Employee referral program
• Educational assistance

Tools and technologies you may use

• Cobalt Strike, Havoc, Mythic, Sliver
• Git, BloodHound
• PowerShell, C, C++, Python
• EDR/AV

Certifications

• Must hold a DoD 8570/8140-compliant Information Assurance Technical (IAT) Level II or Level III certification, along with an offensive security certification.
• Offensive Security Certification (any one): GIAC Penetration Tester (GPEN); Red Team Apprentice Course (RTAC); or equivalent.
• IAT Level II options: CompTIA Security+ CE; CompTIA CySA+ ; CCNA Security; GICSP; GSEC; SSCP.
• IAT Level III options: CompTIA CASP+ CE (SecurityX); CISSP (or Associate); CISA; CCNP Security; GCED; GCIH.

Preferred qualifications

• Experience supporting Red Team or offensive cybersecurity operations.
• Experience with web application, network, wireless, cloud, or infrastructure penetration testing.
• Familiarity with tools such as Nmap, Burp Suite, Metasploit, BloodHound, Wireshark, or similar security testing tools.
• Knowledge of common attack frameworks and methodologies, including MITRE ATT&CK.
• Experience developing penetration testing reports and presenting technical findings.
• Active industry-recognized cybersecurity certifications such as OSCP, CEH, PenTest+, GPEN, or comparable certifications.