Security of an In-orbit Satellite: Detection of Compromise Through Integrity

Security of an In-orbit Satellite: Detection of Compromise Through Integrity

Small satellites are increasingly vulnerable to cyberattacks, yet their resource constraints make implementing robust security mechanisms a significant challenge. This thesis explores how to protect the integrity of satellite and payload data against malicious software running in orbit, a problem that has received limited attention in the satellite security research community.

Poster: Multi-Objective Model Selection Pipeline for Network Flow Classification at POSTERS 2026

Poster: Multi-Objective Model Selection Pipeline for Network Flow Classification at POSTERS 2026

Training classifiers for network intrusion detection is hindered by two types of problems: data challenges (lack of labels, class imbalance, non-IID data, and concept drift) and engineering challenges (memory & compute efficiency, data ingestion, parallel training, and hyperparameter optimization). Existing ad-hoc scripts make it hard to reproduce results or compare models systematically across these conditions. An extendable machine learning pipeline is developed to address both, targeting malicious network flow classifiers for the Stratosphere Linux IPS (Slips). The output is a set of best-performing models at different FPR and F1 thresholds suitable for deployment in Slips.

Dean's Award Outstanding Teaching "Lecturer Category" to Sebastian Garcia

Dean's Award Outstanding Teaching "Lecturer Category" to Sebastian Garcia

Sebastian has just been awarded by the Dean of the Faculty of Electrical Engineering, Czech Technical University in Prague, for his outstanding teaching performance in the Winter Semester 2025/2026!

NetSecGame v0.2.0 - Reproducible Experiments and a More Robust Game Server

NetSecGame v0.2.0 - Reproducible Experiments and a More Robust Game Server

NetSecGame v0.2.0 is here. This release focuses on what matters most for reproducible AI research: deterministic episode control, a more robust simulation server, and a significantly expanded test suite. Whether you are running large-scale RL experiments or debugging a new agent, v0.2.0 makes the process more reliable.

Adaptive Response in Slips IDS as Immune T Cells

Adaptive Response in Slips IDS as Immune T Cells

The T Cell module was created to give Slips a stateful adaptive response layer on top of its existing evidence pipeline. While the original detectors already provide the innate immune component through PAMP and DAMP evidence, the T Cell module adds antigen recognition, co-stimulation, context evaluation, tolerance, activation, effector action, and memory. It does this by extracting structured antigens from live evidence, matching them against the accepted regex repertoire generated by RegexGenerator, and then combining that recognition with the cumulative danger signaled by recent PAMP and DAMP observations. This allows Slips to move from isolated detections to a more explicit immune decision process that can decide when to ignore, when to contain, and when to remember.

Adapting Detections in Slips with Immune Pseudo-Generated Regexes

Adapting Detections in Slips with Immune Pseudo-Generated Regexes

The RegexGenerator module was created to give Slips an adaptive way to discover new string-based detectors for changing indicators such as domains, URIs, filenames, TLS SNI values, and certificate common names. It continuously uses the shared LLM service to propose one regex at a time, then applies local validation and negative selection against benign corpora to reject unsafe or overly broad patterns. The accepted regexes become a reusable adaptive recognition repertoire for other modules, especially the T Cell responder.

HTTPS Anomaly Detection in Slips: Adaptive Baselines for Real Traffic

HTTPS Anomaly Detection in Slips: Adaptive Baselines for Real Traffic

The new HTTPS anomaly detection module in Slips builds per-host adaptive baselines in traffic time, then detects deviations at two levels: per-flow (for bytes to known servers) and per-hour (for host behavior like new servers, unique servers, JA3 changes, and flow volume). It uses online statistics and z-scores for transparent scoring, plus controlled adaptation states (training_fit, drift_update, suspicious_update) to keep learning while reducing poisoning risk.
The result is explainable, operational evidence in clear human text: what changed, confidence, and why it is anomalous.

Rethinking Cybersecurity Defense: Principles from Biological Immunity

Rethinking Cybersecurity Defense: Principles from Biological Immunity

Our research identifies sixteen fundamental principles of biological immunity and translates them into cybersecurity defense architectures that emphasize multi-dimensional coordination over single- point tactics.

NetSecGame - A Framework for Training and Evaluating AI Agents in Network Security Environments

NetSecGame - A Framework for Training and Evaluating AI Agents in Network Security Environments

We are excited to announce the release of NetSecGame (NSG) v0.1.0, a framework for training and evaluating AI agents in network security environments. Developed at the Stratosphere Laboratory at CTU in Prague, NSG provides a highly configurable testbed for both offensive and defensive security tasks.