Junior 5G Protocol Security Researcher

CACI International; Florham Park (NJ); On-site; USD 79,000 - 163,000; Full time

Job summary

CACI International is seeking a Junior Vulnerability Researcher focused on 5G protocol security and firmware reverse engineering. You will own research tasks, analyze 3GPP protocol behavior, and develop automated tooling to secure national mobile infrastructure.

The role requires strong systems background, experience in C/C++, Python3, and familiarity with 4G/5G protocols. You will work within a high-performing team in a security-focused environment and contribute to national security missions.

Qualifications

• Active Top Secret clearance required.
• 3–5 years of professional experience in software exploitation, reverse engineering, or protocol development.
• Strong proficiency in C/C++ and Python3 scripting.
• Working knowledge of 4G/5G architecture and networking protocols (TCP/IP, SCTP, HTTP/2).
• Experience with disassembly tools: IDA Pro, Ghidra, Binary Ninja.
• Foundational binary analysis and memory corruption primitives.
• Demonstrated ability to conduct independent technical research and analyze complex software systems.

Responsibilities

• Execute research into 3GPP protocols (NGAP, GTP, etc.) to identify crashes and logic flaws using stateful fuzzing techniques.
• Perform static and dynamic analysis on compiled telecom binaries and firmware to understand undocumented protocol logic.
• Support the development of custom Python3 scripts for protocol decoding and automating analysis of “closed-box” systems.
• Assist in mapping state machines within 5G session management flows using symbolic or concolic execution tools.
• Analyze signaling and data plane components to identify potential attack surfaces in 5G Core and RAN environments.
• Use debugging tools and packet analysis software (e.g., Wireshark) to inspect protocol traffic and hardware state.
• Document research findings and contribute to the development of technical security reports.

Skills

Top Secret clearance

3–5 years experience

C/C++

Python3 scripting

4G/5G networking

binary analysis

memory corruption concepts

independent research

Tools

IDA Pro

Ghidra

Binary Ninja

Job description

CACI International is seeking a Junior Vulnerability Researcher focused on 5G protocol security and firmware reverse engineering. You will own research tasks, analyze 3GPP protocol behavior, and develop automated tooling to secure national mobile infrastructure.

The role requires strong systems background, experience in C/C++, Python3, and familiarity with 4G/5G protocols. You will work within a high-performing team in a security-focused environment and contribute to national security missions.