SearcharxivSearch

arXiv subjects

Max Landauer

Publications and source records attributed to Max Landauer.

15 recordsLinked to original sources

Just Testing, Move Along: Evasion of LLM-based System Log Interpretation by Prompt Injection

Large Language Models (LLMs) are increasingly integrated into Security Operations Center (SOC) workflows, where they support analysts in tasks such as the interpretation of system logs. However, the ability of LLMs to directly process untrusted textual input also introduces new attack surfaces. In particular, attackers can inject contextual information or explicit instructions into log entries in order to influence how malicious activity is interpreted by the model. Despite the growing adoption of LLMs for log analytics, the robustness of such systems against adversarial log injection remains largely unexplored. To address this gap, this paper presents a framework for evaluating prompt injection attacks against LLM-based log interpretation. Using log traces generated during real cyber attacks, our approach creates adversarial examples through generic injection generation, refinement, and attack-specific optimization. Our evaluation across multiple state-of-the-art LLMs shows that these injections can cause malicious log traces to be classified as benign despite containing clear indicators of compromise. As a potential remedy, we show that the explanations generated by the LLMs alongside their classifications frequently contain indicators of adversarial manipulation that can be leveraged to detect such attacks.

cs.CR

Beyond RAG for Cyber Threat Intelligence: A Systematic Evaluation of Graph-Based and Agentic Retrieval

Cyber threat intelligence (CTI) analysts must answer complex questions over large collections of narrative security reports. Retrieval-augmented generation (RAG) systems help language models access external knowledge, but traditional vector retrieval often struggles with queries that require reasoning over relationships between entities such as threat actors, malware, and vulnerabilities. This limitation arises because relevant evidence is often distributed across multiple text fragments and documents. Knowledge graphs address this challenge by enabling structured multi-hop reasoning through explicit representations of entities and relationships. However, multiple retrieval paradigms, including graph-based, agentic, and hybrid approaches, have emerged with different assumptions and failure modes. It remains unclear how these approaches compare in realistic CTI settings and when graph grounding improves performance. We present a systematic evaluation of four RAG architectures for CTI analysis: standard vector retrieval, graph-based retrieval over a CTI knowledge graph, an agentic variant that repairs failed graph queries, and a hybrid approach combining graph queries with text retrieval. We evaluate these systems on 3,300 CTI question-answer pairs spanning factual lookups, multi-hop relational queries, analyst-style synthesis questions, and unanswerable cases. Results show that graph grounding improves performance on structured factual queries. The hybrid graph-text approach improves answer quality by up to 35 percent on multi-hop questions compared to vector RAG, while maintaining more reliable performance than graph-only systems.

cs.AI

CAM-LDS: Cyber Attack Manifestations for Automatic Interpretation of System Logs and Security Alerts

Log data are essential for intrusion detection and forensic investigations. However, manual log analysis is tedious due to high data volumes, heterogeneous event formats, and unstructured messages. Even though many automated methods for log analysis exist, they usually still rely on domain-specific configurations such as expert-defined detection rules, handcrafted log parsers, or manual feature-engineering. Crucially, the level of automation of conventional methods is limited due to their inability to semantically understand logs and explain their underlying causes. In contrast, Large Language Models enable domain- and format-agnostic interpretation of system logs and security alerts. Unfortunately, research on this topic remains challenging, because publicly available and labeled data sets covering a broad range of attack techniques are scarce. To address this gap, we introduce the Cyber Attack Manifestation Log Data Set (CAM-LDS), comprising seven attack scenarios that cover 81 distinct techniques across 13 tactics and collected from 18 distinct sources within a fully open-source and reproducible test environment. We extract log events that directly result from attack executions to facilitate analysis of manifestations concerning command observability, event frequencies, performance metrics, and intrusion detection alerts. We further present an illustrative case study utilizing an LLM to process the CAM-LDS. The results indicate that correct attack techniques are predicted perfectly for approximately one third of attack steps and adequately for another third, highlighting the potential of LLM-based log interpretation and utility of our data set.

cs.CR

Resource-Aware Deployment Optimization for Collaborative Intrusion Detection in Layered Networks

Collaborative Intrusion Detection Systems (CIDS) are increasingly adopted to counter cyberattacks, as their collaborative nature enables them to adapt to diverse scenarios across heterogeneous environments. As distributed critical infrastructure operates in rapidly evolving environments, such as drones in both civil and military domains, there is a growing need for CIDS architectures that can flexibly accommodate these dynamic changes. In this study, we propose a novel CIDS framework designed for easy deployment across diverse distributed environments. The framework dynamically optimizes detector allocation per node based on available resources and data types, enabling rapid adaptation to new operational scenarios with minimal computational overhead. We first conducted a comprehensive literature review to identify key characteristics of existing CIDS architectures. Based on these insights and real-world use cases, we developed our CIDS framework, which we evaluated using several distributed datasets that feature different attack chains and network topologies. Notably, we introduce a public dataset based on a realistic cyberattack targeting a ground drone aimed at sabotaging critical infrastructure. Experimental results demonstrate that the proposed CIDS framework can achieve adaptive, efficient intrusion detection in distributed settings, automatically reconfiguring detectors to maintain an optimal configuration, without requiring heavy computation, since all experiments were conducted on edge devices.

cs.CR

AlertBERT: A noise-robust alert grouping framework for simultaneous cyber attacks

Automated detection of cyber attacks is a critical capability to counteract the growing volume and sophistication of cyber attacks. However, the high numbers of security alerts issued by intrusion detection systems lead to alert fatigue among analysts working in security operations centres (SOC), which in turn causes slow reaction time and incorrect decision making. Alert grouping, which refers to clustering of security alerts according to their underlying causes, can significantly reduce the number of distinct items analysts have to consider. Unfortunately, conventional time-based alert grouping solutions are unsuitable for large scale computer networks characterised by high levels of false positive alerts and simultaneously occurring attacks. To address these limitations, we propose AlertBERT, a self-supervised framework designed to group alerts from isolated or concurrent attacks in noisy environments. Thereby, our open-source implementation of AlertBERT leverages masked-language-models and density-based clustering to support both real-time or forensic operation. To evaluate our framework, we further introduce a novel data augmentation method that enables flexible control over noise levels and simulates concurrent attack occurrences. Based on the data sets generated through this method, we demonstrate that AlertBERT consistently outperforms conventional time-based grouping techniques, achieving superior accuracy in identifying correct alert groups.

cs.CR

AttackMate: Realistic Emulation and Automation of Cyber Attack Scenarios Across the Kill Chain

Adversary emulation tools facilitate scripting and automated execution of cyber attack chains, thereby reducing costs and manual expert effort required for security testing, cyber exercises, and intrusion detection research. However, due to the fact that existing tools typically rely on agents installed on target systems, they leave suspicious traces that make it easy to distinguish their activities from those of real human attackers. Moreover, these tools often lack relevant capabilities, such as handling of interactive prompts, and are unsuitable for emulating specific stages of the kill chain, such as initial access. This paper thus introduces AttackMate, an open-source attack scripting language and execution engine designed to mimic behavior patterns of actual attackers. We validate the tool in a case study covering common attack steps including privilege escalation, information gathering, and lateral movement. Our results indicate that log artifacts resulting from AttackMate's activities resemble those produced by human attackers more closely than those generated by standard adversary emulation tools.

cs.CR

StealthCup: Realistic, Multi-Stage, Evasion-Focused CTF for Benchmarking IDS

Intrusion Detection Systems (IDS) are critical to defending enterprise and industrial control environments, yet evaluating their effectiveness under realistic conditions remains an open challenge. Existing benchmarks rely on synthetic datasets (e.g., NSL-KDD, CICIDS2017) or scripted replay frameworks, which fail to capture adaptive adversary behavior. Even MITRE ATT&CK Evaluations, while influential, are host-centric and assume malware-driven compromise, thereby under-representing stealthy, multi-stage intrusions across IT and OT domains. We present StealthCup, a novel evaluation methodology that operationalizes IDS benchmarking as an evasion-focused Capture-the-Flag competition. Professional penetration testers engaged in multi-stage attack chains on a realistic IT/OT testbed, with scoring penalizing IDS detections. The event generated structured attacker writeups, validated detections, and PCAPs, host logs, and alerts. Our results reveal that out of 32 exercised attack techniques, 11 were not detected by any IDS configuration. Open-source systems (Wazuh, Suricata) produced high false-positive rates >90%, while commercial tools generated fewer false positives but also missed more attacks. Comparison with the Volt Typhoon APT advisory confirmed strong realism: all 28 applicable techniques were exercised, 19 appeared in writeups, and 9 in forensic traces. These findings demonstrate that StealthCup elicits attacker behavior closely aligned with state-sponsored TTPs, while exposing blind spots across both open-source and commercial IDS. The resulting datasets and methodology provide a reproducible foundation for future stealth-focused IDS evaluation.

cs.CR

System Log Parsing with Large Language Models: A Review

Log data provides crucial insights for tasks like monitoring, root cause analysis, and anomaly detection. Due to the vast volume of logs, automated log parsing is essential to transform semi-structured log messages into structured representations. Recent advances in large language models (LLMs) have introduced the new research field of LLM-based log parsing. Despite promising results, there is no structured overview of the approaches in this relatively new research field with the earliest advances published in late 2023. This work systematically reviews 29 LLM-based log parsing methods. We benchmark seven of them on public datasets and critically assess their comparability and the reproducibility of their reported results. Our findings summarize the advances of this new research field, with insights on how to report results, which data sets, metrics and which terminology to use, and which inconsistencies to avoid, with code and results made publicly available for transparency.

cs.LG

Trace of the Times: Rootkit Detection through Temporal Anomalies in Kernel Activity

Kernel rootkits provide adversaries with permanent high-privileged access to compromised systems and are often a key element of sophisticated attack chains. At the same time, they enable stealthy operation and are thus difficult to detect. Thereby, they inject code into kernel functions to appear invisible to users, for example, by manipulating file enumerations. Existing detection approaches are insufficient, because they rely on signatures that are unable to detect novel rootkits or require domain knowledge about the rootkits to be detected. To overcome this challenge, our approach leverages the fact that runtimes of kernel functions targeted by rootkits increase when additional code is executed. The framework outlined in this paper injects probes into the kernel to measure time stamps of functions within relevant system calls, computes distributions of function execution times, and uses statistical tests to detect time shifts. The evaluation of our open-source implementation on publicly available data sets indicates high detection accuracy with an F1 score of 98.7\% across five scenarios with varying system states.

cs.CR

Towards Improving IDS Using CTF Events

In cybersecurity, Intrusion Detection Systems (IDS) serve as a vital defensive layer against adversarial threats. Accurate benchmarking is critical to evaluate and improve IDS effectiveness, yet traditional methodologies face limitations due to their reliance on previously known attack signatures and lack of creativity of automated tests. This paper introduces a novel approach to evaluating IDS through Capture the Flag (CTF) events, specifically designed to uncover weaknesses within IDS. CTFs, known for engaging a diverse community in tackling complex security challenges, offer a dynamic platform for this purpose. Our research investigates the effectiveness of using tailored CTF challenges to identify weaknesses in IDS by integrating them into live CTF competitions. This approach leverages the creativity and technical skills of the CTF community, enhancing both the benchmarking process and the participants' practical security skills. We present a methodology that supports the development of IDS-specific challenges, a scoring system that fosters learning and engagement, and the insights of running such a challenge in a real Jeopardy-style CTF event. Our findings highlight the potential of CTFs as a tool for IDS evaluation, demonstrating the ability to effectively expose vulnerabilities while also providing insights into necessary improvements for future implementations.

cs.CR

Red Team Redemption: A Structured Comparison of Open-Source Tools for Adversary Emulation

Red teams simulate adversaries and conduct sophisticated attacks against defenders without informing them about used tactics in advance. These interactive cyber exercises are highly beneficial to assess and improve the security posture of organizations, detect vulnerabilities, and train employees. Unfortunately, they are also time-consuming and expensive, which often limits their scale or prevents them entirely. To address this situation, adversary emulation tools partially automate attacker behavior and enable fast, continuous, and repeatable security testing even when involved personnel lacks red teaming experience. Currently, a wide range of tools designed for specific use-cases and requirements exist. To obtain an overview of these solutions, we conduct a review and structured comparison of nine open-source adversary emulation tools. To this end, we assemble a questionnaire with 80 questions addressing relevant aspects, including setup, support, documentation, usability, and technical features. In addition, we conduct a user study with domain experts to investigate the importance of these aspects for distinct user roles. Based on the evaluation and user feedback, we rank the tools and find MITRE Caldera, Metasploit, and Atomic Red Team on top.

cs.CR

A Critical Review of Common Log Data Sets Used for Evaluation of Sequence-based Anomaly Detection Techniques

Log data store event execution patterns that correspond to underlying workflows of systems or applications. While most logs are informative, log data also include artifacts that indicate failures or incidents. Accordingly, log data are often used to evaluate anomaly detection techniques that aim to automatically disclose unexpected or otherwise relevant system behavior patterns. Recently, detection approaches leveraging deep learning have increasingly focused on anomalies that manifest as changes of sequential patterns within otherwise normal event traces. Several publicly available data sets, such as HDFS, BGL, Thunderbird, OpenStack, and Hadoop, have since become standards for evaluating these anomaly detection techniques, however, the appropriateness of these data sets has not been closely investigated in the past. In this paper we therefore analyze six publicly available log data sets with focus on the manifestations of anomalies and simple techniques for their detection. Our findings suggest that most anomalies are not directly related to sequential manifestations and that advanced detection techniques are not required to achieve high detection rates on these data sets.

cs.LG

Introducing a New Alert Data Set for Multi-Step Attack Analysis

Intrusion detection systems (IDS) reinforce cyber defense by autonomously monitoring various data sources for traces of attacks. However, IDSs are also infamous for frequently raising false positives and alerts that are difficult to interpret without context. This results in high workloads on security operators who need to manually verify all reported alerts, often leading to fatigue and incorrect decisions. To generate more meaningful alerts and alleviate these issues, the research domain focused on multi-step attack analysis proposes approaches for filtering, clustering, and correlating IDS alerts, as well as generation of attack graphs. Unfortunately, existing data sets are outdated, unreliable, narrowly focused, or only suitable for IDS evaluation. Since hardly any suitable benchmark data sets are publicly available, researchers often resort to private data sets that prevent reproducibility of evaluations. We therefore generate a new alert data set that we publish alongside this paper. The data set contains alerts from three distinct IDSs monitoring eight executions of a multi-step attack as well as simulations of normal user behavior. To illustrate the potential of our data set, we experiment with alert prioritization as well as two open-source tools for meta-alert generation and attack graph extraction.

cs.CR

Deep Learning for Anomaly Detection in Log Data: A Survey

Automatic log file analysis enables early detection of relevant incidents such as system failures. In particular, self-learning anomaly detection techniques capture patterns in log data and subsequently report unexpected log event occurrences to system operators without the need to provide or manually model anomalous scenarios in advance. Recently, an increasing number of approaches leveraging deep learning neural networks for this purpose have been presented. These approaches have demonstrated superior detection performance in comparison to conventional machine learning techniques and simultaneously resolve issues with unstable data formats. However, there exist many different architectures for deep learning and it is non-trivial to encode raw and unstructured log data to be analyzed by neural networks. We therefore carry out a systematic literature review that provides an overview of deployed models, data pre-processing mechanisms, anomaly detection techniques, and evaluations. The survey does not quantitatively compare existing approaches but instead aims to help readers understand relevant aspects of different model architectures and emphasizes open issues for future work.

cs.LG

Maintainable Log Datasets for Evaluation of Intrusion Detection Systems

Intrusion detection systems (IDS) monitor system logs and network traffic to recognize malicious activities in computer networks. Evaluating and comparing IDSs with respect to their detection accuracies is thereby essential for their selection in specific use-cases. Despite a great need, hardly any labeled intrusion detection datasets are publicly available. As a consequence, evaluations are often carried out on datasets from real infrastructures, where analysts cannot control system parameters or generate a reliable ground truth, or private datasets that prevent reproducibility of results. As a solution, we present a collection of maintainable log datasets collected in a testbed representing a small enterprise. Thereby, we employ extensive state machines to simulate normal user behavior and inject a multi-step attack. For scalable testbed deployment, we use concepts from model-driven engineering that enable automatic generation and labeling of an arbitrary number of datasets that comprise repetitions of attack executions with variations of parameters. In total, we provide 8 datasets containing 20 distinct types of log files, of which we label 8 files for 10 unique attack steps. We publish the labeled log datasets and code for testbed setup and simulation online as open-source to enable others to reproduce and extend our results.

cs.CR