AI Security Reseacher
- Location
- Cluj-Napoca, Romania
- Type
- Full-time
- Seniority
- Mid-level
- Salary
- Not stated
- Department
- Sandbox & Network Detection
- Languages
- EN
- Posted
- 11 Nov 2026
Verified open 11 Nov 2026 · Source: Greenhouse
About the role
Bitdefender is a cybersecurity leader delivering best-in-class threat prevention, detection, and response solutions worldwide. Guardian over millions of consumer, enterprise, and government environments, Bitdefender is one of the industry’s most trusted experts for eliminating threats, protecting privacy, digital identity and data, and enabling cyber resilience. With deep investments in research and development, Bitdefender Labs discovers hundreds of new threats each minute and validates billions of threat queries daily. The company has pioneered breakthrough innovations in antimalware, IoT security, behavioral analytics, and artificial intelligence and its technology is licensed by more than 180 of the world’s most recognized technology brands. Founded in 2001, Bitdefender has customers in 170+ countries with offices around the world. For more information, visit https://www.bitdefender.com
We are looking for a Security Researcher with strong experience in network attacks and protocols and solid Rust development skills, to identify vulnerabilities in the networking stack, build high-performance offensive and detection tooling, and contribute to models for detecting malicious traffic.
Responsibilities
- Research and exploit vulnerabilities in network protocols and implementations (TCP/IP, TLS, DNS, HTTP/2–3, QUIC, VPN, routing, Wi-Fi) and in exposed devices and services.
- Develop security testing tools in Rust: protocol fuzzers, scanners, packet crafting, traffic parsers and high-performance detection components.
- Reverse engineer proprietary protocols and network firmware/services; write PoCs and exploits for the vulnerabilities identified.
- Emulate network attack techniques (lateral movement, MITM, tunneling, C2, exfiltration) and build datasets and signatures for detection.
- Collaborate with the ML team on feature engineering and traffic anomaly detection models.
Requirements
- 3–5+ years of experience in network security / offensive security / research;
- Very good knowledge of network attacks and of how protocols work at the packet level; experience with Wireshark, Scapy, nmap, Burp or equivalents;
- Hands-on Rust experience (async, tokio, FFI, socket-level or raw-packet networking); Python for prototyping and analysis;
- Strong Linux experience (netfilter/eBPF, namespaces, network stack) and with virtualized test labs;
- Hands-on infrastructure pentesting or vulnerability research experience, with demonstrable results (CVEs, advisories, published tools, write-ups).
Nice to have
- Applied ML on network traffic (anomaly detection, classification, PyTorch / scikit-learn);
- Experience with eBPF/XDP, DPDK or other high-speed packet processing technologies;
- Firmware reverse engineering (IoT, routers, embedded devices);
- Malware analysis with a focus on C2 communication and custom protocols;
- Participation in CTFs (pwn/network categories) or bug bounty programs.
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