Serhii Romanko

Serhii Romanko is a senior security consultant at K2 Integrity/Leviathan Security Group, where he provides security architecture guidance and conducts comprehensive security assessments across applications and cloud environments. With almost a decade of cybersecurity experience, he conducts black- and white-box penetration testing, source code review, and security configuration reviews of cloud platforms, including AWS and […]

Viktoriia Reitsenshtein

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Viktoriia Reitsenshtein is a senior security consultant at K2 Integrity/Leviathan Security Group. She provides security architecture guidance and performs black-, gray-, and white-box penetration testing of applications. Her work also includes security research and development, as well as training and mentoring junior security consultants. Her technical expertise spans web and mobile application penetration testing, cloud […]

Amina Murtazina

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Amina Murtazina is a security consultant with K2 Integrity/Leviathan Security Group, where she provides expertise across a broad spectrum of cybersecurity disciplines. Her work spans security architecture guidance, black- and white-box application penetration testing, auditing, and security research and development. She supports clients in strengthening their security posture by applying a rigorous approach to identifying […]

Jeffery Frazier

Jeffery Frazier is a security consultant and a member of K2 Integrity/Leviathan Security Group’s Technical Services team. He specializes in hardware and application security penetration testing and security evaluations, bringing nearly two decades of hands-on experience across secure development, offensive and defensive tool engineering, and secure command-and-control communications systems. Jeffery’s technical expertise spans application and […]

A.J. Butt

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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

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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

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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

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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 […]