Cryptography and Security
BackFlush: Knowledge-Free Backdoor Detection and Elimination with Watermark Preservation in Large Language Models
Jagadeesh Rachapudi, Ritali Vatsi, Pranav Singh et al. (+2 more)
In recent trends, one can observe Large
Language Models (LLMs) are exposed to
backdoor attacks where vicious triggers added during training or model editing to elicit harmful outputs on specific input patterns while maintaining clean performance on normal inputs. Legitimate watermarks used as ownership signatures share similar mechanisms to
backdoors, creating a critical challenge: detecting and eliminating unknown
backdoors without compromising watermark integrity. Existing defenses require prior knowledge of triggers or their payloads, depend on clean reference models, or sacrifice model utility without preserving the watermark. To address these limitations we introduce BackFlush and its variants, a unified framework for
backdoor detection and elimination while preserving watermarks. We establish two novel observations:
Backdoor Flushing Phenomenon, where injecting and unlearning auxiliary data eliminates pre established
backdoors, and
Backdoor Susceptibility Amplification, enabling constant time detection independent of vocabulary size. BackFlush employs Rotation based Parameter Editing (RoPE) Unlearning, a technique that preserves watermarks while eliminating
backdoors by rotating the
embeddings. Comprehensive evaluation across diverse trigger types over different architectures demonstrates BackFlush achieves approximately 1%Attack Success Rate (ASR), approximately 99% clean accuracy (CACC), and preserved watermarking capabilities in the realm where no existing method simultaneously provides these alongside maintaining model utility comparable to clean baselines. Codes are available at https://github.com/JagadeeshAI/BackFlush IJCNN.git.
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All authors Jagadeesh Rachapudi, Ritali Vatsi, Pranav Singh, Praful Hambarde, Amit Shukla
Cryptography and Security · Cross-listed from cs.DC
HadAgent: Harness-Aware Decentralized Agentic AI Serving with Proof-of-Inference Blockchain Consensus
Landy Jimenez, Mariah Weatherspoon, Bingyu Shen et al. (+3 more)
Proof-of-Work (PoW) blockchain consensus consumes vast computational resources without producing useful output, while the rapid growth of large
language model (LLM)
agents has created unprecedented demand for GPU computation. We present HadAgent, a decentralized agentic AI serving system that replaces hash-based mining with Proof-of-Inference (PoI), a consensus mechanism in which nodes earn block-creation rights by executing deterministic LLM inference tasks. Because verification requires only re-executing a single forward pass under identical conditions, cross-node verification operates at consensus speed. HadAgent organizes validated records into a three-lane block body with dedicated DATA, MODEL, and PROOF channels, each protected by an independent Merkle root for fine-grained tamper detection. A two-tier node architecture classifies secondary nodes as trusted or non-trusted based on historical behavior: trusted nodes serve inference results in real time through optimistic execution, while non-trusted nodes must undergo full consensus verification. A harness layer monitors node behavior through heartbeat probes, anomaly detection via deterministic recomputation, and automated trust management, creating a self-correcting feedback loop that isolates malicious or unreliable participants. Experiments on a prototype implementation demonstrate 100% detection rate and 0% false positive rate for tampered records, sub-millisecond validation latency for record and hub operations, and effective harness convergence that excludes
adversarial nodes within two rounds while promoting honest nodes to trusted status within five rounds.
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All authors Landy Jimenez, Mariah Weatherspoon, Bingyu Shen, Yi Sheng, Jianming Liu, Boyang Li
Cryptography and Security · Cross-listed from cs.CV
Penny Wise, Pixel Foolish: Bypassing Price Constraints in Multimodal Agents via Visual Adversarial Perturbations
Jiachen Qian and Zhaolu Kang
The rapid proliferation of
Multimodal Large
Language Models (MLLMs) has enabled mobile
agents to execute high-stakes financial transactions, but their
adversarial robustness remains underexplored. We identify Visual Dominance
Hallucination (VDH), where imperceptible visual cues can override textual price evidence in screenshot-based, price-constrained settings and lead
agents to irrational decisions. We propose PriceBlind, a stealthy white-box
adversarial attack framework for controlled screenshot-based evaluation. PriceBlind exploits the modality gap in CLIP-based encoders via a Semantic-Decoupling Loss that aligns the image
embedding with low-cost, value-associated anchors while preserving pixel-level fidelity. On E-ShopBench, PriceBlind achieves around 80% ASR in white-box evaluation; under a simplified single-turn coordinate-selection protocol, Ensemble-DI-FGSM transfers with roughly 35-41% ASR across GPT-4o, Gemini-1.5-Pro, and Claude-3.5-Sonnet. We also show that robust encoders and Verify-then-Act defenses reduce ASR substantially, though with some clean-accuracy trade-off.
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Cryptography and Security · Cross-listed from cs.AR
VeriCWEty: Embedding enabled Line-Level CWE Detection in Verilog
Prithwish Basu Roy, Zeng Wang, Anatolii Chuvashlov et al. (+4 more)
Large
Language Models (LLMs) have shown significant improvement in RTL code generation. Despite the advances, the generated code is often riddled with common vulnerabilities and weaknesses (CWEs) that can slip by untrained eyes. Attackers can often exploit these weaknesses to fulfill their nefarious motives. Existing RTL bug-detection techniques rely on rule-based checks, formal properties, or coarse-grained structural analysis, which either fail to capture semantic vulnerabilities or lack precise localization. In our work, we bridge this gap by proposing an
embedding-based bug-detection framework that detects and classifies bugs at both module and line-level granularity. Our method achieves about 89% precision in identifying common CWEs such as CWE-1244 and CWE-1245, and 96% accuracy in detecting line-level bugs.
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All authors Prithwish Basu Roy, Zeng Wang, Anatolii Chuvashlov, Weihua Xiao, Johann Knechtel, Ozgur Sinanoglu, Ramesh Karri
Cryptography and Security
The Synthetic Media Shift: Tracking the Rise, Virality, and Detectability of AI-Generated Multimodal Misinformation
Zacharias Chrysidis, Stefanos-Iordanis Papadopoulos and Symeon Papadopoulos
As generative AI advances, the distinction between authentic and synthetic media is increasingly blurred, challenging the integrity of online information. In this study, we present CONVEX, a large-scale
dataset of
multimodal misinformation involving miscaptioned, edited, and AI-generated visual content, comprising over 150K
multimodal posts with associated notes and engagement metrics from X's Community Notes. We analyze how
multimodal misinformation evolves in terms of virality, engagement, and consensus dynamics, with a focus on synthetic media. Our results show that while AI-generated content achieves disproportionate virality, its spread is driven primarily by passive engagement rather than active discourse. Despite slower initial reporting, AI-generated content reaches community consensus more quickly once flagged. Moreover, our evaluation of specialized detectors and
vision-
language models reveals a consistent decline in performance over time in distinguishing synthetic from authentic images as generative models evolve. These findings highlight the need for continuous monitoring and adaptive strategies in the rapidly evolving digital information environment.
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Cryptography and Security
TopFeaRe: Locating Critical State of Adversarial Resilience for Graphs Regarding Topology-Feature Entanglement
Xinxin Fan, Wenxiong Chen, Quanliang Jing et al. (+4 more)
Graph
adversarial attacks are usually produced from the two perspectives of
topology/structure and node feature, both of them represent the paramount characteristics learned by today's deep learning models. Although some defense countermeasures are proposed at present, they fails to disclose the intrinsic reasons why these two aspects necessitate and how they are adequately fused to co-learn the graph representation. Towards this question, we in this paper propose an
adversarial defense approach through locating the graph's critical state of
adversarial resilience, resorting to the
equilibrium-point theory in the discipline of complex dynamic system (CDS). In brief, our work has three novelties: i)
Adversarial-Attack Modeling, i.e. map a graph regime into CDS, and use the oscillation of dynamic system to model the behavior of
adversarial perturbation; ii) 2D
Topology-Feature-Entangled Function Design for Perturbed Graph, i.e. project graph
topology and node feature as two characteristic spaces, and define two-dimensional entangled perturbation functions to represent the dynamic variance under
adversarial attacks; and iii) Location of Critical State of
Adversarial Resilience, i.e. utilize the
equilibrium-point theory to locate the graph's critical state of attack resilience resorting to the perturbation-reflected 2D function. Finally, multi-facet experiments on five commonly-used realistic
datasets validate the effectiveness of our proposed approach, and the results show our approach can significantly outperform the state-of-the-art baselines under four representative graph
adversarial attacks.
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All authors Xinxin Fan, Wenxiong Chen, Quanliang Jing, Chi Lin, Shaoye Luo, Wenbo Song, Yunfeng Lu
Cryptography and Security
An Agentic Workflow for Detecting Personally Identifiable Information in Crash Narratives
Junyi Ma, Pei Li, Rui Gan et al. (+3 more)
Crash narratives in crash reports provide crucial contextual information for traffic safety analysis. Yet, their broader use is hindered by the presence of personally identifiable information (PII), including names, home addresses, and license plate numbers. Because PII appears sparsely and inconsistently in crash narratives, manual detection is not scalable, and existing rule-based approaches often fail to capture context-dependent PII. This study develops and evaluates a locally deployable, agentic workflow for PII detection in crash narratives by leveraging large
language models (LLMs). The workflow contains a Hybrid Extractor and a Verifier. The Hybrid Extractor routes structured PII (e.g., phone numbers and email addresses) to a rule-based model (i.e., Presidio) and context-dependent PII (e.g., names, home addresses, and alphanumeric identifiers) to a domain-adapted, fine-tuned LLM. To address ambiguity in challenging categories, the workflow incorporates ensemble LLM extraction and an agentic verification step that filters false detections through evidence-based
reasoning. Evaluated on a real-world crash
dataset, the agentic workflow achieves strong performance with a precision of 0.82, a recall of 0.94, an F1 of 0.87, and an accuracy of 0.96, outperforming multiple baseline methods. Moreover, the ablation results suggest that ensemble LLM extraction and Verifier offer improved detection for home addresses and alphanumeric identifiers. The workflow runs locally, supporting
privacy-sensitive operational settings where external APIs are restricted. This work offers a practical and robust path for scalable,
privacy-preserving crash data processing, enabling broader research and safety interventions while safeguarding individual
privacy.
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All authors Junyi Ma, Pei Li, Rui Gan, Kai Cheng, Steven T. Parker, Bin Ran
Cryptography and Security
LogJack: Indirect Prompt Injection Through Cloud Logs Against LLM Debugging Agents
Harsh Shah
LLM debugging
agents that consume cloud logs and execute remediation commands are vulnerable to indirect
prompt injection through log content. We present LogJack, a
benchmark of 42 payloads across 5 cloud log categories, and evaluate 8 foundation models under 3
prompt conditions with 5 independent trials each (n = 160 per model per condition on 32 attack payloads). Under the active condition, verbatim command execution rates range from 0% (Claude Sonnet 4.6) to 86.2% (Llama 3.3 70B). Passive instructions ("do not execute fixes") reduce most models to 0% but Llama still executes at 30.0%. Remote code execution via curl | bash succeeds on 6 of 8 models. Guardrails from AWS, GCP, and Azure largely fail to detect log-embedded injections-Azure
Prompt Shield detected only the most obvious payload (1/32), while GCP Model Armor detected none-though they detect identical payloads in isolation. We also observe a novel "sanitize and execute" behavior where a model detects and removes an obvious malicious component but still executes the remaining injected command.
Benchmark and harness available at github.com/HarshShah1997/logjack.
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Cryptography and Security
SoK: Security of Autonomous LLM Agents in Agentic Commerce
Qian'ang Mao, Jiaxin Wang, Ya Liu et al. (+3 more)
Autonomous large
language model (LLM)
agents such as OpenClaw are pushing agentic commerce from human-supervised assistance toward machine actors that can negotiate, purchase services, manage digital assets, and execute transactions across on-chain and off-chain environments. Protocols such as the Trustless
Agents standard (ERC-8004),
Agent Payments Protocol (AP2), OKX
Agent Payments Protocol (APP), the HTTP 402-based payment protocol (x402),
Agent Commerce Protocol (ACP), the Agentic Commerce standard (ERC-8183), and Machine Payments Protocol (MPP) enable this transition, but they also create an attack surface that existing security frameworks do not capture well. This Systematization of Knowledge (SoK) develops a unified security framework for autonomous LLM
agents in commerce and finance. We organize threats along five dimensions:
agent integrity, transaction authorization, inter-
agent trust,
market manipulation, and regulatory compliance. From a systematically curated public corpus of academic papers, protocol documents, industry reports, and incident evidence, we derive 12 cross-layer attack vectors and show how failures propagate from
reasoning and tooling layers into custody, settlement,
market harm, and compliance exposure. We then propose a layered defense architecture addressing authorization gaps left by current
agent-payment protocols. Overall, our analysis shows that securing agentic commerce is inherently a cross-layer problem that requires coordinated controls across LLM safety, protocol design, identity,
market structure, and regulation. We conclude with a research roadmap and a
benchmark agenda for secure autonomous commerce.
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All authors Qian'ang Mao, Jiaxin Wang, Ya Liu, Li Zhu, Cong Ma, Jiaqi Yan
Cryptography and Security
NeuroTrace: Inference Provenance-Based Detection of Adversarial Examples
Firas Ben Hmida, Philemon Hailemariam, Kashif Ali Khan et al. (+1 more)
Deep neural networks (DNNs) remain largely opaque at inference time, limiting our ability to detect and diagnose malicious input manipulations such as
adversarial examples. Existing detection methods predominantly rely on layer-local signals (e.g., activations or attribution scores), leaving cross-layer information flow and execution structure under-explored. We introduce NeuroTrace, a framework and open
dataset for analyzing inference provenance through Inference Provenance Graphs (IPGs). IPGs are heterogeneous graphs that capture both activation behavior and parameter-induced dataflow during a model's forward pass, providing a structured representation of how information propagates through the network. NeuroTrace includes (i) a reproducible extraction engine that instruments model execution, (ii) a standardized graph representation compatible with heterogeneous GNNs, and (iii) a
benchmark suite spanning multiple
adversarial attack families across
vision and malware domains. Using this framework, we evaluate IPG-based detectors for
adversarial example detection under intra-attack, multi-attack, and cross-threat transfer settings. Our results show that inference provenance provides a strong and transferable signal for distinguishing
adversarial and benign inputs, achieving consistently high detection performance and improving over prior graph-based baselines. We further analyze the conditions under which provenance-based detection generalizes across attack types, as well as the associated runtime and storage trade-offs. By releasing the
dataset, extraction pipeline, and evaluation protocol, NeuroTrace enables systematic study of inference-time behavior and establishes inference provenance as a practical foundation for building more transparent and auditable machine learning systems.
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All authors Firas Ben Hmida, Philemon Hailemariam, Kashif Ali Khan, Birhanu Eshete
Cryptography and Security
Robustness Analysis of Machine Learning Models for IoT Intrusion Detection Under Data Poisoning Attacks
Fortunatus Aabangbio Wulnye, Justice Owusu Agyemang, Kwame Opuni-Boachie Obour Agyekum et al. (+3 more)
Ensuring the reliability of machine learning-based intrusion detection systems remains a critical challenge in Internet of Things (IoT) environments, particularly as data poisoning attacks increasingly threaten the integrity of model training pipelines. This study evaluates the susceptibility of four widely used classifiers, Random Forest, Gradient Boosting Machine, Logistic Regression, and Deep Neural Network models, against multiple poisoning strategies using three real-world IoT
datasets. Results show that while ensemble-based models exhibit comparatively stable performance, Logistic Regression and Deep Neural Networks suffer degradation of up to 40% under label manipulation and outlier-based attacks. Such disruptions significantly distort decision boundaries, reduce detection fidelity, and undermine deployment readiness. The findings highlight the need for adversarially robust training, continuous anomaly monitoring, and feature-level validation within operational Network Intrusion Detection Systems. The study also emphasizes the importance of integrating resilience testing into regulatory and compliance frameworks for AI-driven IoT security. Overall, this work provides an empirical foundation for developing more resilient intrusion detection pipelines and informs future research on adaptive, attack-aware models capable of maintaining reliability under
adversarial IoT conditions.
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All authors Fortunatus Aabangbio Wulnye, Justice Owusu Agyemang, Kwame Opuni-Boachie Obour Agyekum, Kwame Agyeman-Prempeh Agyekum, Kingsford Sarkodie Obeng Kwakye, Francisca Adomaa Acheampong
Cryptography and Security
AndroScanner: Automated Backend Vulnerability Detection for Android Applications
Harini Dandu
Mobile applications rely on complex backends that introduce significant security risks, yet developers often lack the tools to assess these risks effectively. This paper presents AndroScanner, an automated pipeline for detecting vulnerabilities in Android application backends through combined static and dynamic analysis. AndroScanner extracts backend API calls from APK files using apktool, Androguard, and Frida-based dynamic instrumentation, then vets them against the OWASP API Security Top 10 using APIFuzzer. We evaluate AndroScanner on two Android applications: a purposely vulnerable bank application and a production recruitment application with over 50,000 downloads on Google Play Store. Across both applications, AndroScanner extracted 24 APIs and identified 5 vulnerabilities, including a previously unreported zero-day Excessive Data Exposure vulnerability (ranked 3rd in the OWASP API Security Top 10) in the production application. The vulnerability was responsibly disclosed to the development team prior to publication. AndroScanner is available upon request to assist developers in identifying and remediating backend security risks before deployment.
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Cryptography and Security
Digital Guardians: The Past and The Future of Cyber-Physical Resilience
Saurabh Bagchi, Hyunseung Kim, Tarek Abdelzaher et al. (+20 more)
Resilience in cyber-physical systems (CPS) is the fundamental ability to maintain safety and critical functionality despite adverse "perturbations," which includes security attacks, environmental disruptions, and hardware or software failures. This survey provides a comprehensive review of CPS resilience, framing the field through five interconnected themes that are required in an integrated whole to achieve real-world resilience. The article first posits that resilience is a system-wide property emerging from interactions between hardware, software, and human users. Second, it addresses the challenges of learning-enabled CPS, which often operate in data-scarce environments characterized by imbalanced or noisy data, requiring innovative solutions like synthetic data generation and foundation model adaptation. Third, the survey examines proactive measures for resilience, which include distinctive aspects of verification, testing, and redundancy. Fourth, it explores recovery mechanisms, moving beyond traditional fault models to design "just good enough" recovery strategies that prioritize safety-critical functions during perturbations. Finally, it highlights the central role of the human, focusing on the different levels of human intervention, the necessity of trust calibration, and the requirement for explainable AI to support human-CPS teaming. These themes are illustrated through representative application domains, primarily Connected and Autonomous Transportation Systems (CATS) and Medical CPS (MCPS). By integrating the five interconnected themes, this survey provides a systematic roadmap for achieving the resilient CPS in increasingly complex and
adversarial environments.
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All authors Saurabh Bagchi, Hyunseung Kim, Tarek Abdelzaher, Homa Alemzadeh, Somali Chaterji, Glen Chou, Yuying Duan, Fanxin Kong, Michael Lemmon, Yin Li, Mengyu Liu, Wenhao Luo, Meiyi Ma, Sibin Mohan, Ayan Mukhopadhyay, Melkior Ornik, Dimitra Panagou, Kristin Yvonne Rozier, Ivan Ruchkin, Huajie Shao, Sze Zheng Yong, Majid Zamani, Xugui Zhou
Cryptography and Security · Cross-listed from cs.PL
Filament: Denning-Style Information Flow Control for Rust
Jeffrey C. Ching, Quan Zhou and Danfeng Zhang
Existing
language-based information-flow control (IFC) tools face a fundamental tension: Denning-style systems that track explicit and implicit flows at the variable level typically require compiler modifications, while more coarse-grained approaches, including recent work Cocoon, avoid compiler changes but impose more restrictive programming models. We present Filament, a Denning-style static IFC library for Rust that requires no compiler modifications. Filament addresses three key challenges in building a practical IFC library for Rust. First, it enables fine-grained explicit-flow checking with minimal annotation overhead by leveraging Rust's type inference. Second, it introduces pc_block!, a lightweight construct for enforcing implicit flows via a compile-time program counter label, without requiring compiler support. Third, it provides fcall! and mcall! macros to support seamless and safe interoperability with standard and third-party libraries. Our evaluation shows that Filament incurs negligible compile-time overhead and requires only modest annotations. Moreover, compared to Cocoon, Filament offers a more permissive programming model, reducing the need for frequent escape hatches that bypass security checks.
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Cryptography and Security
"Setting up TLS authentication was hell": A Usability Study of Client Certificate Authentication
Abubakar Sadiq Shittu, Clay Shubert, John Sadik et al. (+1 more)
"Cryptography turns a security problem into a key management problem." Despite decades of research effort towards usable key management, it remains unclear whether key management issues are inherent to every cryptographic system or merely artifacts of specific designs. To investigate, this paper presents a user study of mutual TLS (mTLS) usability, tracking 46 senior and graduate computer science students, highly technical users who configured client certificates, used them for routine authentication over a semester-long course, and managed credentials across multiple devices. Our results show that initial setup and setting up credentials on a second device are difficult, while routine authentication is easy once configured. Nevertheless, perceived usability remained low, and alarmingly, only 9 percent of participants fully understood mTLS security implications and key management. Our findings demonstrate that usability challenges shift across the credential lifecycle depending on system architecture. We conclude by offering design recommendations for future key management systems to better support users across the complete credential lifecycle.
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All authors Abubakar Sadiq Shittu, Clay Shubert, John Sadik, Scott Ruoti
Cryptography and Security
Challenges and Future Directions in Agentic Reverse Engineering Systems
Salem Radey, Jack West and Kassem Fawaz
Agentic systems built on large
language models (LLMs) are increasingly being used for complex security tasks, including binary reverse engineering (RE). Despite recent growth in popularity and capability, these systems continue to face limitations in realistic settings. Cutting-edge systems still fail in complex RE scenarios that involve obfuscation, timing, and unique architecture. In this work, we examine how agentic systems perform reverse engineering tasks with static, dynamic, and hybrid
agents. Through an analysis of existing agentic tool usage, we identify several limitations, including
token constraints, struggles with obfuscation, and a lack of program guardrails. From these findings, we outline current challenges and position future directions for system designers to overcome from a security perspective.
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Cryptography and Security
Head Count: Privacy-Preserving Face-Based Crowd Monitoring
Fatemeh Marzani, Thijs van Ede, Geert Heijenk et al. (+1 more)
An important aspect of crowd monitoring is knowing how many people we are dealing with. Sometimes, knowing the size of a crowd in a single location and at a specific moment is enough. Matters become problematic when counting the same people across dif ferent locations or counting them over longer periods of time. In those cases, we need to identify and later reidentify a person, which immediately leads to
privacy concerns. Until recently, solutions have been based on unique identification of carry-on devices, yet
privacy improvements have caused transmitted information to be randomized, rendering this technique mostly useless. We propose to use biometric data instead. We introduce a pipeline that counts people based on face recognition, yet without ever being able to reveal the identity of individuals. To count, a camera initially detects a face, extracts its features, and derives an identifier using a fuzzy extractor. The original facial image is then deleted. Identifiers are inserted into homomorphically encrypted Bloom filters. This allows oblivious set membership testing directly on encrypted data, enabling the system to count across locations or across different moments, without revealing any identities. We provide an initial evaluation of our method that shows promising results.
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All authors Fatemeh Marzani, Thijs van Ede, Geert Heijenk, Maarten van Steen