Senior Offensive Cybersecurity Engineer

Parry Labs, LLC is seeking a Senior Offensive Cybersecurity Engineer to lead authorized offensive security assessments in support of mission-focused systems. The role operates in a structured testing environment, pairing hands-on testing with threat modeling, security tooling, and repeatable verification so teams can validate risk and confirm fixes.

This position is based in Alexandria, VA with onsite requirements, with an expected start in November 2026. The ideal candidate brings 7+ years of security engineering experience, including offensive testing or vulnerability research, and the ability to produce reproducible evidence for security decisions.

Responsibilities

• Develop threat models and security test plans tied to system requirements and potential failure modes.
• Define authorized test scope, rules of engagement, and stop conditions with program stakeholders.
• Conduct penetration testing, protocol analysis, and vulnerability research in approved environments.
• Build protocol and parser fuzzing tools.
• Add repeatable security checks to automated test workflows.
• Assess Linux services and network interfaces.
• Review Rust or C/C++ code for security weaknesses.
• Evaluate authentication, digital signatures, replay protection, and key handling in collaboration with software and cryptographic engineers.
• Document reproducible findings, impact, and remediation priorities.
• Retest fixes and preserve test evidence.
• Support red-team and blue-team exercises.
• Keep assessment signoff separate from implementation ownership.

Requirements

• Bachelor’s degree in cybersecurity, computer science, engineering or a related field, or equivalent relevant experience.
• 7+ years of security engineering experience, including hands-on offensive testing or vulnerability research.
• Experience with authorized penetration testing, protocol analysis, fuzzing, and vulnerability assessment.
• Ability to review Rust or C/C++ and develop security test tooling in Python or a systems language.
• Experience analyzing Linux and network behavior, including TCP/IP, service configuration, and access controls.
• Experience producing reproducible findings, explaining security impact, and verifying remediation with engineering teams.
• U.S. citizenship and eligibility to obtain and maintain a U.S. government security clearance if required. An active clearance is not required at hire.

Technologies

• Rust, C/C++, Python
• Linux, TCP/IP
• Cryptographic algorithms, post-quantum algorithms
• Hardware security modules (HSMs), key management

Preferred Qualifications

• Experience testing positioning, navigation and timing (PNT), distributed systems, or embedded devices.
• Knowledge of applied cryptography, post-quantum algorithms, hardware security modules, or key management.
• Experience with source-code security reviews, secure implementation practices, or side-channel analysis.
• Experience with DoD security testing, STIG verification, or Risk Management Framework assessment evidence.

Accessibility/Accommodation

If you need a reasonable accommodation for any part of the employment process due to a medical condition or disability, contact [email protected] or call (256) 682-7145 to provide the nature of your request and your contact information.