A.J. Butt
A.J. Butt is a security consultant with K2 Integrity/Leviathan Security Group, delivering technical security services across a wide range of project sizes and practice areas. His work includes black- and white-box web application and web services testing, internal and external network infrastructure testing, cloud configuration review, adversary simulation, native device and host review, and source […]
Vitalii Asieiev
Vitalii Asieiev is a security consultant with K2 Integrity/Leviathan Security Group, with a focus on security architecture guidance, black‑ and white‑box application penetration testing, auditing, and security research and development. Vitalii leads research and development initiatives focused on the security of web, API, and cloud‑based systems in commercial environments, identifying security risks, developing proof‑of‑concept exploits, […]
Andrii Apostol
Andrii Apostol is a software engineer with K2 Integrity/Leviathan Security Group, with expertise in system architecture, distributed computing, and high-performance enterprise solutions. He brings a broad technological background that includes .NET and Node.js development, SQL/NoSQL databases, microservices, and DevOps automation, enabling him to build scalable, secure, and resilient systems across diverse technology environments. With a […]
Sofia Aberegg
Sofia Aberegg is a security consultant in K2 Integrity/Leviathan Security Group’s Technical Services team, specializing in web application penetration testing, exploit development, and secure code review. She brings deep technical expertise across offensive security testing, secure development practices, and vulnerability research to help organizations identify and mitigate complex security risks. In addition to client engagements, […]
Thomas Pieragastini
As senior technical lead at K2 Integrity/Leviathan Security Group, Thomas Pieragastini specializes in infrastructure security, operating system security and exploitation, and the testing of new or novel targets. He leads complex engagements focused on identifying and mitigating critical vulnerabilities across enterprise systems and cloud and AI infrastructure. Tom’s technical expertise spans operating system and domain […]
Phil Pena
As a senior security consultant with K2 Integrity/Leviathan Security Group’s technical services team, Phil Pena brings extensive expertise in hardware security and reverse engineering. He leads a wide range of security engagements, including open‑ and closed‑source application penetration testing, hardware security auditing, code review, and security best‑practice training. At K2 Integrity/Leviathan Security Group, Phil leverages […]
Tom Overbey
Tom Overbey is a senior security risk advisor and team lead for K2 Integrity/Leviathan Security Group. He works with clients to understand their security risk maturity and response agility, identify how to close their vulnerability gaps, and reduce their overall risk. Tom’s expertise has been developed around the strategy and deployment of tabletop exercises by […]
Juliette D. Moss
Juliette D. Moss is a senior member of K2 Integrity/Leviathan Security Group’s technical services team, where she specializes in complex application security penetration testing, secure code review, threat modeling, and attack surface analysis. She brings more than two decades of hands-on experience in system IT maintenance, programming, and virtual machine configuration, combining deep technical knowledge […]
Robee Krishan
Robee Krishan is a senior security risk advisor for K2 Integrity/Leviathan Security Group. With expertise in cybersecurity, privacy compliance, and risk management, Robee helps organizations safeguard their data and navigate complex security frameworks. She specializes in conducting risk assessments and developing policies and procedures, as well as guiding clients through standards such as ISO 27001, […]
Frank Heidt
A recognized expert in the fields of information assurance, network security, and systems penetration, Frank Heidt brings together security professionals with diverse backgrounds from premier consultancies, industries, and government agencies to design and deliver cybersecurity services and programs that impact the world’s most influential companies. Prior to forming K2 Integrity/Leviathan Security Group, Frank was a […]