Senior Security Tester (Penetration Testing)

EPAM Systems; Turkey; Remote; TRY 6,030,000 - 9,045,000; Full time

Job summary

EPAM Systems Inc. seeks a research-minded Senior Security Tester at the intersection of OT/ICS security, exploit development, and AI/LLM security. You will break real industrial environments safely, write exploits, and assess AI/agentic systems while delivering engagements end-to-end.

You will map findings to ISA/IEC 62443, NIST 800-82 and MITRE ATT&CK for ICS, crafting practical remediation for plant operations and collaborating with engineers and executives.

Qualifications

• 5+ years of hands-on penetration testing and offensive security, including depth in at least two areas: OT/ICS, exploit development/vulnerability research, or AI/LLM security.
• Demonstrated OT/ICS penetration testing experience on real industrial environments or high-fidelity labs, with strong safety-first testing practices.
• Showcase of original vulnerability research through CVEs, advisories or exploits, conference talks, or bug bounty/CTF results.
• Hands-on experience testing LLM applications or agentic AI systems, understanding how models, retrieval, tools and permissions create attack surface.

Responsibilities

• Plan and execute safety-first penetration tests of OT/ICS environments (water, energy, manufacturing, building systems), including asset discovery, Purdue-model segmentation testing and IT-to-OT pivot analysis.
• Assess PLCs, RTUs, HMIs, SCADA servers, historians and engineering workstations across major vendors and SCADA platforms.
• Test industrial protocols such as Modbus/TCP, DNP3, EtherNet/IP/CIP, S7comm, OPC UA, BACnet and IEC 60870-5-104/61850 for authentication, integrity and logic manipulation weaknesses.
• Build and use lab or digital-twin replicas to validate attack paths before touching production, operating within client-approved rules of engagement and safety constraints.
• Map findings to ISA/IEC 62443, NIST SP 800-82 and MITRE ATT&CK for ICS, with remediation guidance realistic for plant operations.
• Conduct vulnerability research on binaries, firmware, embedded/IoT devices, web applications and enterprise software using reverse engineering, source code review and fuzzing.
• Write reliable proof-of-concept and weaponized exploits for memory corruption, logic flaws and authentication bypasses.
• Deliver client engagements end to end and communicate findings clearly to engineers and executives.

Skills

OT/ICS security

Exploit development

AI/LLM security

Python

C/C++

x86/x64

ARM assembly

Bash/PowerShell

Reverse engineering

Debugging tools

Education

Bachelor's degree in Computer Science, Information Security or related field

Tools

IDA Pro

Ghidra

Binary Ninja

AFL++

libFuzzer

boofuzz

Burp Suite

Metasploit

Nmap

Job description

We are seeking a research-minded Senior Security Tester who sits at the intersection of three disciplines: operational technology (OT/ICS) security, exploit development and zero-day discovery, and offensive testing of AI and agentic systems. This is not a scanner-driven role — you will break real industrial environments safely, write working exploits for vulnerabilities you find yourself, and attack LLM applications and autonomous agents the way a capable adversary would. You will deliver client engagements end-to-end, contribute original research to the customer's zero-day program, and help build the AI-driven tooling that scales our offensive capability.ResponsibilitiesPlan and execute safety-first penetration tests of OT/ICS environments (water and wastewater, energy, manufacturing, building systems), including passive asset discovery, Purdue-model segmentation testing and IT-to-OT pivot analysisAssess PLCs, RTUs, HMIs, SCADA servers, historians and engineering workstations across major vendors and SCADA platformsTest industrial protocols such as Modbus/TCP, DNP3, EtherNet/IP/CIP, S7comm, OPC UA, BACnet and IEC 60870-5-104/61850 for authentication, integrity and logic-manipulation weaknessesBuild and use lab or digital-twin replicas to validate attack paths before touching production, and operate strictly within client-approved rules of engagement, change windows and safety constraintsMap findings to ISA/IEC 62443, NIST SP 800-82 and MITRE ATT&CK for ICS, with remediation guidance that is realistic for plant operationsConduct vulnerability research on binaries, firmware, embedded/IoT devices, web applications and enterprise software using reverse engineering, source code review and fuzzingWrite reliable proof-of-concept and weaponized exploits for memory corruption, logic flaws and authentication bypassesDeliver client engagements end to end and communicate findings clearly to both engineers and executivesRequirementsMinimum 5 years of hands-on penetration testing and offensive security experience, including significant depth in at least two of: OT/ICS security, exploit development/vulnerability research, and AI/LLM securityDemonstrated OT/ICS penetration testing experience on real industrial environments or high-fidelity labs, with a strong grasp of safety-first testing practicesShowcase of original vulnerability research through CVE credits, published advisories or exploits, conference talks, or high-level bug bounty/CTF resultsHands-on experience testing LLM applications or agentic AI systems, with a working understanding of how models, retrieval, tools and permissions combine to create attack surfaceProficiency in Python, C/C++, x86/x64 and ARM assembly, and Bash/PowerShell; Rust or Go a plusProficiency with reverse engineering and debugging tools (IDA Pro, Ghidra, Binary Ninja), fuzzers (AFL++, libFuzzer, boofuzz) and offensive tooling (Burp Suite, Metasploit, Nmap)Familiarity with industry standards and frameworks including OWASP Top 10, CVE/CWE, OSSTMM, NIST, MITRE ATT&CK, ISA/IEC 62443 and MITRE ATLASBachelor's degree in Computer Science, Information Security, Electrical/Control Engineering or a related field or equivalent practical experienceExcellent written and spoken English, with the ability to convey complex technical concepts to technical and non-technical audiencesBased in Europe and eligible to work through EPAM, able to overlap with US business hours for client meetings, and available for occasional travel when requiredWe offerCONTINUOUS UPSKILLING, LEARNING & DEVELOPMENTDiversity of tasks and projectsAssessment center for objective review of competency levelPersonal development planMentoring programs and leadership developmentCertification and professional development supportAccess to learning platforms including more than 2,500 internal coursesEnglish courses taught by certified teachersCORPORATE BENEFITSExtra leave daysReferral bonusesCOMPENSATION PACKAGECompetitive compensation paid in USDRegular salary and performance reviewsMEDICAL & HEALTHCAREPrivate health insuranceWell-being eventsWORKING ENVIRONMENTRecreation areas and kitchensTea, coffee and snacksSports equipment and game consolesIT EquipmentMicrosoft’s Software Assurance Home Use Program (HUP)Please note that our Talent Attraction Team reviews applications and CVs submitted in English.EPAM is global leader in AI transformation engineering and integrated consulting, serving Forbes Global 2000 companies and ambitious startups. With over thirty years of expertise in custom software, product and platform engineering, we empower our clients to become AI-Native enterprises, driving measurable value from innovation and digital investments.