Senior AI Security Researcher — LLM Post-Training & Eval

Jobs Paloaltonetworks; California (MO); On-site; USD 163,000 - 264,000; Full time

Job summary

Palo Alto Networks is seeking a Sr Principal AI Researcher to advance cybersecurity capabilities of large language models and autonomous AI agents. You’ll combine security research with rigorous evaluation and applied post‑training methods across vulnerability research, threat analysis, detection, and remediation.

Work across security research, ML, and engineering to identify model capability gaps and translate real‑world cybersecurity problems into measurable improvements.

Qualifications

• Strong hands-on experience in one or more cybersecurity areas, such as vulnerability research, secure coding, threat detection, malware analysis, incident investigation, reverse engineering, fuzzing, or security automation.
• Practical experience developing or evaluating LLM‑based systems for cybersecurity, source code, software engineering, or tool‑using agents.
• Experience designing datasets, benchmarks, graders, evaluation frameworks, or tasks with verifiable outcomes.
• Experience with at least one post-training or model-adaptation method, such as supervised fine‑tuning, preference optimization, reinforcement learning, reward modeling, synthetic data generation, or distillation.
• Strong programming skills in Python and at least one system or application language, such as C, C++, Rust, Java, or Go.
• Experience working with large codebases, security tools, testing frameworks, build systems, debuggers, and containerized environments.
• Strong understanding of experimental design, failure analysis, regression testing, and quantitative evaluation.
• Ability to independently drive ambiguous research problems from investigation through implementation and validation.
• BS/MS degree in Computer Science, Machine Learning, Artificial Intelligence, Cybersecurity, or a related field, or equivalent practical experience.

Responsibilities

• Design reproducible training and evaluation environments for complex cybersecurity tasks, including vulnerability research, threat analysis, detection, investigation, remediation, secure coding, and autonomous security workflows.
• Transform source-code repositories, vulnerabilities, security incidents, malware samples, threat intelligence, detection logic, patches, test harnesses, and security tools into structured tasks for LLMs and AI agents.
• Develop high‑quality security datasets, including synthetic data, hard negatives, adversarial examples, expert annotations, and model‑generated trajectories.
• Build reliable graders, verifiers, and reward signals using tests, compilation, runtime behavior, security‑tool outputs, detection results, vulnerability reproduction, and other domain‑specific validation methods.
• Design evaluations for security reasoning, code understanding, threat analysis, root‑cause analysis, tool use, long‑horizon execution, and autonomous task completion.
• Analyze model failures, data quality issues, grader weaknesses, reward hacking, benchmark overfitting, and capability regressions.
• Develop and evaluate post‑training methods, including supervised fine‑tuning, preference optimization, reinforcement learning, reward modeling, rejection sampling, and distillation.
• Build iterative model‑improvement loops using model rollouts, verifier feedback, expert review, synthetic data generation, and failure‑driven data collection.
• Conduct controlled experiments with appropriate baselines, ablations, and regression testing.
• Collaborate with Security Researchers, ML Engineers, infrastructure teams, and product teams to move research into production capabilities.

Skills

Cybersecurity

Vulnerability research

Secure coding

Threat detection

Malware analysis

Incident investigation

Reverse engineering

Fuzzing

Security automation

Python

C/C++/Rust/Java/Go

Education

BS/MS in CS/ML/AI/Cybersecurity

Tools

Debuggers

Containerized environments

Build systems

Testing frameworks

Security tools

Job description

Palo Alto Networks is seeking a Sr Principal AI Researcher to advance cybersecurity capabilities of large language models and autonomous AI agents. You’ll combine security research with rigorous evaluation and applied post‑training methods across vulnerability research, threat analysis, detection, and remediation.

Work across security research, ML, and engineering to identify model capability gaps and translate real‑world cybersecurity problems into measurable improvements.