About Us

Berezha Security is one of the most successful cybersecurity consultancies in Ukraine. We commit to the highest quality in the field while keeping our rates affordable to small and medium businesses.



years in business

happy clients

successful projects


Why Berezha Security?

We guarantee free retests of all timely fixes, -15% discount for regular clients, and professional liability insurance.

We maintain profound experience in application security, penetration testing, bounty hunting, and security audit.

Our clients are in fintech, banking, IT, telecom, finance, agriculture, legal services, oil and gas, and many other industries.

We adjust to any working culture and project management style. Our experts hold the most prestigious certificates.

We focus on your unique threat model, attack landscape, and risk profile, instead of fitting in the "best practice."

We commit to ultimate quality, timely delivery, repeatable results, detailed reporting, and zero negative impact.


Professional Certificates

Offensive Security OSCP

More Info

The Offensive Security Certified Professional certification is a unique evaluation of offensive security skills based on a 24-hour hands-on exam that proves such areas of expertise as network penetration testing, vulnerability identification, and exploitation along with proper documentation and reporting of issues identified.


More Info

A Certified Information Systems Security Professional certificate proves skills and experience needed to effectively design, implement and manage a best-in-class cybersecurity program, including risk management, architecture, communication, and network security, access management, security operations, and application security.


More Info

The Certified Information Systems Auditor designation is a globally recognized certification for IS audit control, assurance, and security professionals. It proves audit experience, skills, and knowledge, and demonstrates the capability to assess vulnerabilities, report on compliance and institute controls within the enterprise.

eLearnSecurity eWPTX

More Info

Web Application Penetration Tester eXtreme is the most practical and advanced certification for the assessment of web application penetration testing skills. The examination is based on an actual penetration test on a web application, which requires a combination of methodologies and a comprehensive report on findings.

eLearnSecurity eMAPT

More Info

Mobile Application Penetration Tester is the certificate issued to Mobile Application Security Experts who demonstrate their hands-on skills through a comprehensive and 100% practical exam, which proves the skills to confidently identify and exploit vulnerable mobile applications.

EC-Council CEH

More Info

A Certified Ethical Hacker certificate proves the skills to look for weaknesses and vulnerabilities in target systems and use the same knowledge and tools as a malicious hacker, but in a lawful and legitimate manner to assess the security posture of a target system.


Executive Team

Kos Korsun

Executive Director

More Info

As former deputy head of Cybercrime Division at Security Service of Ukraine, Kostyantyn was one of the founders and the first head of CERT-UA. After resigning from the service, Kos acted as Regional Director for the Ukrainian Research Office of iSIGHT Partners, an international cyber threat intelligence company. He was a co-founder and first Chairman of the Ukrainian Information Security Group and a long-term head of its UISGCON annual conference organization team.

Currently, Kos is active in the Ukrainian cybersecurity community and executes strategic leadership for Berezha Security.

Andriy Varusha


More Info

Andriy is an accomplished manager with 10+ years of experience in various industry verticals. He has started his carrier in IT Audit and Consulting and continued in Enterprise IT and Software Development services. Andriy has experience of leading customer relationships within the US, UK, and Western Europe geographies, being responsible for distributed teams and permanent engagements of different scale.

Andriy has stood at the root of the Ukrainian cybersecurity professional community and has joined Berezha to advance his contribution to the development of the cybersecurity industry.

Vlad Styran

VP, Business Development

More Info

Vlad is an internationally known cybersecurity expert with 15+ years of experience in Penetration Testing, security audits, and consulting. Vlad currently holds OSCP, CISSP, and CISA credentials and was certified as C|EH, ISO27001LA, and many more throughout his career. Vlad is a leader of the OWASP Kyiv chapter, a co-founder of the NoNameCon cybersecurity conference, and a speaker on the topics of Social Engineering threats and Penetration Testing methods and techniques.

At Berezha, Vlad is responsible for steady growth and building relationships with our customers.

Get in touch to know more

Call Us

+1 (315) 303 2323
+380 (44) 364 7336


6 Nimanska St., 41, Kyiv, Ukraine 01103


77 Sichovykh Striltsiv St., Kyiv, Ukraine