Windows CNO Developer

About Legato, LLC

Legato, LLC is a dynamic small business headquartered in Columbia, near Ft. Meade, MD. Our positions include Cyber, Software, Systems, Networking, Data Science and other complex engineering capabilities. We set ourselves apart by having employees in the top of their field and who enjoy working at Legato for its attention to its employees, aggressive compensation, and upward mobility possibilities.

What You Will Do:

• Research, identify, and characterize Windows kernel vulnerabilities, including privilege escalation, sandbox escapes, and persistence mechanisms.
• Design, develop, and maintain CNO/CNE tools and capabilities targeting Windows platforms (kernel and user mode), from proof-of-concept to operational-grade capability.
• Perform advanced reverse engineering of Windows binaries, drivers, and system components to understand behavior, exploitability, and mitigation paths using tools like IDA Pro, Ghidra, and WinDbg.
• Develop kernel-mode and user-mode code in C/C++ and Assembly to implement implants, loaders, and exploit chains, with a focus on reliability and stealth.
• Create and test exploitation techniques for complex Windows targets, including bypasses for modern protections (ASLR, DEP, CFG, kernel mitigations), in partnership with cyber research teams.
• Integrate CNO capabilities into mission frameworks and tasking/dataflow pipelines, including configuration, logging, and secure communications.
• Conduct debugging and troubleshooting of low-level software in lab and operational-like environments, including crash triage and performance analysis.
• Collaborate closely with analysts, operators, and other engineers to align capabilities with mission requirements and provide technical guidance on feasibility and trade-offs.
• Produce clear technical documentation (designs, CONOPs, usage guides) and contribute to secure coding standards and internal best practices.

Our minimum requirements for this role:

• Active TS/SCI clearance.
• 7-10+ years of professional software development focused on low-level or systems programming, with significant experience on Windows.
• Demonstrated, hands-on Windows kernel vulnerability research experience: analyzing kernel internals, developing PoCs, and understanding exploitability and mitigations.
• Strong proficiency in C and C++, plus experience with Python for tooling/automation and x86/x64 Assembly for exploit and implant development.
• Deep understanding of Windows internals (kernel architecture, memory management, process/thread model, I/O, driver model, security mechanisms, and Windows APIs).
• Experience with reverse engineering tools such as IDA Pro, Ghidra, WinDbg, x64dbg, or similar, and comfort reading disassembly and decompiled code.
• Solid knowledge of networking protocols (TCP/IP, HTTP(S), DNS) and socket programming relevant to CNE tool communications and C2 channels.
• Experience with secure software development lifecycle: design, develop, test, debug, document, and maintain complex codebases, preferably in Agile teams.
• Familiarity with version control (Git) and modern dev toolchains (Visual Studio, CMake, CI workflows).

Preferred Skills and Qualifications

• Prior work developing CNO/CNE capabilities.
• Experience evading host and network defenses (EDR/AV, IDS/IPS) and building resiliency/OPSEC into tooling.
• Experience with other platforms (Linux, mobile, or embedded) and cross-platform CNO development

Benefits

• Individual and family health benefits
• Vision benefits
• Dental benefits
• A minimum of four (4) weeks of paid time off
• A week of sick leave
• 11 federal holidays off
• 401(k) employer match with no vesting schedule
• Opportunity to earn referral benefits or bank hours if the contract allows.