Junior 5G Vulnerability Researcher

CACI; United States; On-site; USD 79,000 - 163,000; Full time

Benefits offered by this job

Healthcare benefits

Retirement plan

Education support

Time off benefits

Job summary

CACI International Inc. in the United States is seeking a Junior 5G Vulnerability Researcher to join our engineering team, focusing on protocol analysis and firmware reverse engineering across complex telecom stacks.

You will develop automated tooling in Python, perform static/dynamic analysis of 3GPP protocols and binaries, and document security findings to support national mobile infrastructure security efforts.

Qualifications

• 3 years of professional experience in software exploitation, reverse engineering, or protocol development.
• Proficiency in C/C++, Python development.
• Working knowledge of TCP/IP, SCTP, HTTP/2.
• Experience with disassembly tools (IDA Pro, Ghidra, Binary Ninja).
• Foundational binary analysis and memory corruption concepts.

Responsibilities

• Execute research into 3GPP protocols to identify crashes and logic flaws using fuzzing.
• Perform static and dynamic analysis on telecom binaries and firmware.
• Develop Python3 scripts for protocol decoding and automation.
• Map state machines in 5G session management flows using symbolic execution tools.
• Analyze signaling and data plane components to identify attack surfaces.
• Use Wireshark and similar tools to inspect protocol traffic.
• Document research findings and contribute to security reports.

Skills

C/C++

Python

Networking protocols

Disassembly tools

Independent research

Tools

IDA Pro

Ghidra

Binary Ninja

Job description

Job Title: Junior 5G Vulnerability ResearcherJob Category: EngineeringTime Type: Full timeMinimum Clearance Required to Start: NoneEmployee Type: RegularPercentage of Travel Required: NoneType of Travel: None

The Opportunity:

We are seeking a Vulnerability Researcher to join our 5G security team, focusing on protocol analysis and firmware reverse engineering. This role is for a practitioner with a strong systems background who is ready to take ownership of research tasks within complex telecommunications stacks. You will work as part of a high-performing group, identifying security flaws in 3GPP protocols and proprietary telecom binaries while developing the automated tooling necessary to secure national mobile infrastructure.

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 tJools.
• 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.

Qualifications:

• 3 years of professional experience in software exploitation, reverse engineering, or protocol development.
• Proficiency in software development (C/C++, Python).
• Working knowledge of networking protocols (TCP/IP, SCTP, HTTP/2).
• Experience with disassembly tools such as IDA Pro, Ghidra, or Binary Ninja.
• Foundational understanding of binary analysis and memory corruption primitives.
• Demonstrated ability to conduct independent technical research and analyze complex software systems.
• Must be a US Citizen and able to obtain/maintain a security clearance

Desired:

• An active TS SCI clearance.
• Experience with software-defined radio (SDR) or cellular testing equipment.
• Working knowledge of cellular networking protocols (3G, 4G, 5G).
• Familiarity with Linux-based telecom network functions.
• Participation in security research projects or CTFs with a focus on networking or pwnable challenges.

This position is contingent on funding and may not be filled immediately. However, this position is representative of positions within CACI that are consistently available. Individuals who apply may also be considered for other positions at CACI.

What You Can Expect:

A culture of integrity.

At CACI, we place character and innovation at the center of everything we do. As a valued team member, you’ll be part of a high-performing group dedicated to our customer’s missions and driven by a higher purpose - to ensure the safety of our nation.

An environment of trust.

CACI values the unique contributions that every employee brings to our company and our customers - every day. You’ll have the autonomy to take the time you need through a unique flexible time off benefit and have access to robust learning resources to make your ambitions a reality.

A focus on continuous growth.

Together, we will advance our nation's most critical missions, build on our lengthy track record of business success, and find opportunities to break new ground - in your career and in our legacy.

Pay Range:

The proposed salary range for this position is:

$79,400 - $162,700

Benefits:

• At CACI, you will receive comprehensive benefits such as; healthcare, wellness, financial, retirement, family support, continuing education, and time off benefits.

Equal Opportunity Employer:

CACI is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, pregnancy, sexual orientation, age, national origin, disability, status as a protected veteran, or any other protected characteristic.