Cryptography and Security · Cross-listed from cs.LG
A Robust Federated Learning Approach for Combating Attacks Against IoT Systems Under non-IID Challenges
Eyad Gad, Zubair Md Fadlullah and Mostafa M. Fouda
In the context of the growing proliferation of user devices and the concurrent surge in data volumes, the complexities arising from the substantial increase in data have posed formidable challenges to conventional machine learning model training. Particularly, this is evident within resource-constrained and security-sensitive environments such as those encountered in networks associated with the Internet of Things (IoT).
Federated Learning has emerged as a promising remedy to these challenges by decentralizing model training to edge devices or parties, effectively addressing
privacy concerns and resource limitations. Nevertheless, the presence of statistical heterogeneity in non-Independently and Identically Distributed (non-IID) data across different parties poses a significant hurdle to the effectiveness of FL. Many FL approaches have been proposed to enhance learning effectiveness under statistical heterogeneity. However, prior studies have uncovered a gap in the existing research landscape, particularly in the absence of a comprehensive comparison between
federated methods addressing statistical heterogeneity in detecting IoT attacks. In this research endeavor, we delve into the exploration of FL
algorithms, specifically FedAvg, FedProx, and Scaffold, under different data distributions. Our focus is on achieving a comprehensive understanding of and addressing the challenges posed by statistical heterogeneity. In this study, We classify large-scale IoT attacks by utilizing the CICIoT2023
dataset. Through meticulous analysis and experimentation, our objective is to illuminate the performance nuances of these FL methods, providing valuable insights for researchers and practitioners in the domain.
Read the full abstract ▾
Cryptography and Security
Membership Inference Attacks Beyond Overfitting
Mona Khalil, Alberto Blanco-Justicia, Najeeb Jebreel et al. (+1 more)
Membership inference attacks (MIAs) against machine learning (ML) models aim to determine whether a given data point was part of the model training data. These attacks may pose significant
privacy risks to individuals whose sensitive data were used for training, which motivates the use of defenses such as differential
privacy, often at the cost of high accuracy losses. MIAs exploit the differences in the behavior of a model when making predictions on samples it has seen during training (members) versus those it has not seen (non-members). Several studies have pointed out that model overfitting is the major factor contributing to these differences in behavior and, consequently, to the success of MIAs. However, the literature also shows that even non-overfitted ML models can leak information about a small subset of their training data. In this paper, we investigate the root causes of membership inference vulnerabilities beyond traditional overfitting concerns and suggest targeted defenses. We empirically analyze the characteristics of the training data samples vulnerable to MIAs in models that are not overfitted (and hence able to generalize). Our findings reveal that these samples are often outliers within their classes (e.g., noisy or hard to classify). We then propose potential defensive strategies to protect these vulnerable samples and enhance the
privacy-preserving capabilities of ML models. Our code is available at https://github.com/najeebjebreel/mia_analysis.
Read the full abstract ▾
All authors Mona Khalil, Alberto Blanco-Justicia, Najeeb Jebreel, Josep Domingo-Ferrer
Cryptography and Security
RampoNN: A Reachability-Guided System Falsification for Efficient Cyber-Kinetic Vulnerability Detection
Kohei Tsujio, Mohammad Abdullah Al Faruque and Yasser Shoukry
Detecting kinetic vulnerabilities in Cyber-Physical Systems (CPS), vulnerabilities in control code that can precipitate hazardous physical consequences, is a critical challenge. This task is complicated by the need to analyze the intricate coupling between complex software behavior and the system's physical dynamics. Furthermore, the periodic execution of control code in CPS applications creates a combinatorial explosion of execution paths that must be analyzed over time, far exceeding the scope of traditional single-run code analysis. This paper introduces RampoNN, a novel framework that systematically identifies kinetic vulnerabilities given the control code, a physical system model, and a Signal Temporal Logic (STL) specification of safe behavior. RampoNN first analyzes the control code to map the control signals that can be generated under various execution branches. It then employs a neural network to abstract the physical system's behavior. To overcome the poor scaling and loose over-approximations of standard neural network reachability, RampoNN uniquely utilizes Deep Bernstein neural networks, which are equipped with customized reachability
algorithms that yield orders of magnitude tighter bounds. This high-precision reachability analysis allows RampoNN to rapidly prune large sets of guaranteed-safe behaviors and rank the remaining traces by their potential to violate the specification. The results of this analysis are then used to effectively guide a falsification engine, focusing its search on the most promising system behaviors to find actual vulnerabilities. We evaluated our approach on a PLC-controlled water tank system and a switched PID controller for an automotive engine. The results demonstrate that RampoNN leads to acceleration of the process of finding kinetic vulnerabilities by up to 98.27% and superior scalability compared to other state-of-the-art methods.
Read the full abstract ▾
Cryptography and Security
Password Strength Analysis Through Social Network Data Exposure: A Combined Approach Relying on Data Reconstruction and Generative Models
Maurizio Atzori, Eleonora Calò, Loredana Caruccio et al. (+3 more)
Although passwords remain the primary defense against unauthorized access, users often tend to use passwords that are easy to remember. This behavior significantly increases security risks, also due to the fact that traditional password strength evaluation methods are often inadequate. In this discussion paper, we present SODA ADVANCE, a data reconstruction tool also designed to enhance evaluation processes related to the password strength. In particular, SODA ADVANCE integrates a specialized module aimed at evaluating password strength by leveraging publicly available data from multiple sources, including social media platforms. Moreover, we investigate the capabilities and risks associated with emerging Large
Language Models (LLMs) in evaluating and generating passwords, respectively. Experimental assessments conducted with 100 real users demonstrate that LLMs can generate strong and personalized passwords possibly defined according to user profiles. Additionally, LLMs were shown to be effective in evaluating passwords, especially when they can take into account user profile data.
Read the full abstract ▾
All authors Maurizio Atzori, Eleonora Calò, Loredana Caruccio, Stefano Cirillo, Giuseppe Polese, Giandomenico Solimando
Cryptography and Security
AutoBackdoor: Automating Backdoor Attacks via LLM Agents
Yige Li, Zhe Li, Wei Zhao et al. (+4 more)
Backdoor attacks pose a serious threat to the secure deployment of large
language models (LLMs), enabling adversaries to implant hidden behaviors triggered by specific inputs. However, existing methods often rely on manually crafted triggers and static data pipelines, which are rigid, labor-intensive, and inadequate for systematically evaluating modern defense robustness. As AI
agents become increasingly capable, there is a growing need for more rigorous, diverse, and scalable red-teaming frameworks that can realistically simulate
backdoor threats and assess model resilience under
adversarial conditions. In this work, we introduce AutoBackdoor, a general framework for automating
backdoor injection, encompassing trigger generation, poisoned data construction, and model fine-tuning via an autonomous
agent-driven pipeline. Unlike prior approaches, AutoBackdoor uses a powerful
language model
agent to generate semantically coherent, context-aware trigger phrases, enabling scalable poisoning across arbitrary topics with minimal human effort. We evaluate AutoBackdoor under three realistic threat scenarios, including Bias Recommendation,
Hallucination Injection, and Peer Review Manipulation, to simulate a broad range of attacks. Experiments on both open-source and commercial models, including LLaMA-3, Mistral, Qwen, and GPT-4o, demonstrate that our method achieves over 90% attack success with only a small number of poisoned samples. More importantly, we find that existing defenses often fail to mitigate these attacks, underscoring the need for more rigorous and adaptive evaluation techniques against
agent-driven threats as explored in this work. All code,
datasets, and experimental configurations will be merged into our primary repository at https://github.com/bboylyg/BackdoorLLM.
Read the full abstract ▾
All authors Yige Li, Zhe Li, Wei Zhao, Nay Myat Min, Hanxun Huang, Xingjun Ma, Jun Sun
Cryptography and Security
Systematically Deconstructing APVD Steganography and its Payload with a Unified Deep Learning Paradigm
Kabbo Jit Deb, Md. Azizul Hakim and Md Shamse Tabrej
In the era of digital communication, steganography allows covert
embedding of data within media files. Adaptive Pixel Value Differencing (APVD) is a steganographic method valued for its high
embedding capacity and invisibility, posing challenges for traditional steganalysis. This paper proposes a deep learning-based approach for detecting APVD steganography and performing reverse steganalysis, which reconstructs the hidden payload. We present a Convolutional Neural Network (CNN) with an
attention mechanism and two output heads for simultaneous stego detection and payload recovery. Trained and validated on 10,000 images from the BOSSbase and UCID
datasets, our model achieves a detection accuracy of 96.2 percent. It also reconstructs embedded payloads with up to 93.6 percent recovery at lower
embedding densities. Results indicate a strong inverse relationship between payload size and recovery accuracy. This study reveals a vulnerability in adaptive steganography and provides a tool for digital forensic analysis, while encouraging reassessment of data security in the age of AI-driven techniques.
Read the full abstract ▾
Cryptography and Security
Auditable Ledger Snapshot for Non-Repudiable Cross-Blockchain Communication
Tirthankar Sengupta, Bishakh Chandra Ghosh, Sandip Chakraborty et al. (+1 more)
Blockchain interoperability is increasingly recognized as the centerpiece for robust interactions among decentralized services. Blockchain ledgers are generally tamper-proof and thus enforce non-repudiation for transactions recorded within the same network. However, such a guarantee does not hold for cross-blockchain transactions. When disruptions occur due to malicious activities or system failures within one blockchain network, foreign networks can take advantage by denying legitimate claims or mounting fraudulent liabilities against the defenseless network. In response, this paper introduces InterSnap, a novel blockchain snapshot archival methodology, for enabling auditability of crossblockchain transactions, enforcing non-repudiation. InterSnap introduces cross-chain transaction receipts that ensure their irrefutability. Snapshots of ledger data along with these receipts are utilized as non-repudiable proof of bilateral agreements among different networks. InterSnap enhances system resilience through a distributed snapshot generation process, need-based snapshot scheduling process, and archival storage and sharing via decentralized platforms. Through a prototype implementation based on Hyperledger Fabric, we conducted experiments using on-premise machines, AWS public cloud instances, as well as a private cloud infrastructure. We establish that InterSnap can recover from malicious attacks while preserving crosschain transaction receipts. Additionally, our proposed solution demonstrates adaptability to increasing loads while securely transferring snapshot archives with minimal overhead.
Read the full abstract ▾
All authors Tirthankar Sengupta, Bishakh Chandra Ghosh, Sandip Chakraborty, Shamik Sural
Cryptography and Security · Cross-listed from quant-ph
Optimizing Quantum Key Distribution Network Performance using Graph Neural Networks
Akshit Pramod Anchan, Ameiy Acharya and Leki Chom Thungon
This paper proposes an optimization of
Quantum Key Distribution (QKD) Networks using Graph Neural Networks (GNN) framework. Today, the development of
quantum computers threatens the security systems of classical cryptography. Moreover, as QKD networks are designed for protecting secret communication, they suffer from multiple operational difficulties: adaptive to dynamic conditions, optimization for multiple parameters and effective resource utilization. In order to overcome these obstacles, we propose a GNN-based framework which can model QKD networks as dynamic graphs and extracts exploitable characteristics from these networks' structure. The graph contains not only topological information but also specific characteristics associated with
quantum communication (the number of edges between nodes, etc). Experimental results demonstrate that the GNN-optimized QKD network achieves a substantial increase in total key rate (from 27.1 Kbits/s to 470 Kbits/s), a reduced average QBER (from 6.6% to 6.0%), and maintains path integrity with a slight reduction in average transmission distance (from 7.13 km to 6.42 km). Furthermore, we analyze network performance across varying scales (10 to 250 nodes), showing improved link prediction accuracy and enhanced key generation rate in medium-sized networks. This work introduces a novel operation mode for QKD networks, shifting the paradigm of network optimization through adaptive and scalable
quantum communication systems that enhance security and performance.
Read the full abstract ▾
Cryptography and Security · Cross-listed from cs.LG
Optimal Fairness under Local Differential Privacy
Hrad Ghoukasian and Shahab Asoodeh
We investigate how to optimally design local differential
privacy (LDP) mechanisms that reduce data unfairness and thereby improve
fairness in downstream classification. We first derive a closed-form optimal mechanism for binary sensitive attributes and then develop a tractable optimization framework that yields the corresponding optimal mechanism for multi-valued attributes. As a theoretical contribution, we establish that for discrimination-accuracy optimal classifiers, reducing data unfairness necessarily leads to lower classification unfairness, thus providing a direct link between
privacy-aware pre-processing and classification
fairness. Empirically, we demonstrate that our approach consistently outperforms existing LDP mechanisms in reducing data unfairness across diverse
datasets and
fairness metrics, while maintaining accuracy close to that of non-private models. Moreover, compared with leading pre-processing and post-processing
fairness methods, our mechanism achieves a more favorable accuracy-
fairness trade-off while simultaneously preserving the
privacy of sensitive attributes. Taken together, these results highlight LDP as a principled and effective pre-processing
fairness intervention technique.
Read the full abstract ▾
Cryptography and Security
The Shawshank Redemption of Embodied AI: Understanding and Benchmarking Indirect Environmental Jailbreaks
Chunyang Li, Zifeng Kang, Junwei Zhang et al. (+4 more)
The adoption of
Vision-
Language Models (VLMs) in
embodied AI
agents, while being effective, brings safety concerns such as jailbreaking. Prior work have explored the possibility of directly jailbreaking the
embodied agents through elaborated multi-modal
prompts. However, no prior work has studied or even reported indirect jailbreaks in
embodied AI, where a black-box attacker induces a jailbreak without issuing direct
prompts to the
embodied agent. In this paper, we propose, for the first time, indirect environmental jailbreak (IEJ), a novel attack to jailbreak
embodied AI via indirect
prompt injected into the environment, such as malicious instructions written on a wall. Our key insight is that
embodied AI does not ”think twice” about the instructions provided by the environment – a blind trust that attackers can exploit to jailbreak the
embodied agent. We further design and implement open-source prototypes of two fully-automated frameworks: SHAWSHANK, the first automatic attack generation framework for the proposed attack IEJ; and SHAWSHANK-FORGE, the first automatic
benchmark generation framework for IEJ. Then, using SHAWSHANK-FORGE, we automatically construct SHAWSHANK-BENCH, the first
benchmark for indirectly jailbreaking
embodied agents. Together, our two frameworks and one
benchmark answer the questions of what content can be used for malicious IEJ instructions, where they should be placed, and how IEJ can be systematically evaluated. Evaluation results show that SHAWSHANK outperforms eleven existing methods across 3,957 task-scene combinations and compromises all six tested VLMs. Furthermore, current defenses only partially mitigate our attack, and we have responsibly disclosed our findings to all affected VLM vendors.
Read the full abstract ▾
All authors Chunyang Li, Zifeng Kang, Junwei Zhang, Zhuo Ma, Anda Cheng, Xinghua Li, Jianfeng Ma
Cryptography and Security
Multi-Domain Security for 6G ISAC: Challenges and Opportunities in Transportation
Musa Furkan Keskin, Muralikrishnan Srinivasan, Onur Gunlu et al. (+5 more)
Integrated sensing and communication (
ISAC) will be central to 6G-enabled transportation, providing both seamless connectivity and high-precision sensing. However, this tight integration exposes attack points not encountered in pure sensing and communication systems. In this article, we identify unique
ISAC-induced security challenges and opportunities in three interrelated domains: cyber-physical (where manipulation of sensors and actuators can mislead perception and control), physical-layer (where over-the-air signals are vulnerable to spoofing and jamming) and protocol (where complex cryptographic protocols cannot detect lower-layer attacks). Building on these insights, we put forward a multi-domain security
vision for 6G transportation and propose an integrated security framework that unifies protection across domains by leveraging existing
ISAC measurements for lightweight cross-checks.
Read the full abstract ▾
All authors Musa Furkan Keskin, Muralikrishnan Srinivasan, Onur Gunlu, Hui Chen, Panagiotis Papadimitratos, Magnus Almgren, Zhongxia Simon He, Henk Wymeersch
Cryptography and Security
"To Survive, I Must Defect": Jailbreaking LLMs via the Game-Theory Scenarios
Zhen Sun, Zongmin Zhang, Deqi Liang et al. (+8 more)
As LLMs become more common, non-expert users can pose risks, prompting extensive research into jailbreak attacks. However, most existing black-box jailbreak attacks rely on hand-crafted heuristics or narrow search spaces, which limit scalability. Compared with prior attacks, we propose Game-Theory Attack (GTA), an scalable black-box jailbreak framework. Concretely, we formalize the attacker's interaction against safety-aligned LLMs as a finite-horizon, early-stoppable sequential
stochastic game, and reparameterize the LLM's randomized outputs via quantal response. Building on this, we introduce a behavioral
conjecture "template-over-safety flip": by reshaping the LLM's effective objective through game-theoretic scenarios, the originally safety preference may become maximizing scenario payoffs within the template, which weakens safety constraints in specific contexts. We validate this mechanism with classical game such as the disclosure variant of the Prisoner's Dilemma, and we further introduce an Attacker
Agent that adaptively escalates pressure to increase the ASR. Experiments across multiple protocols and
datasets show that GTA achieves over 95% ASR on LLMs such as Deepseek-R1, while maintaining efficiency. Ablations over components, decoding,
multilingual settings, and the
Agent's core model confirm effectiveness and generalization. Moreover, scenario scaling studies further establish scalability. GTA also attains high ASR on other game-theoretic scenarios, and one-shot LLM-generated variants that keep the model mechanism fixed while varying background achieve comparable ASR. Paired with a Harmful-Words Detection
Agent that performs word-level insertions, GTA maintains high ASR while lowering detection under
prompt-guard models. Beyond
benchmarks, GTA jailbreaks real-world LLM applications and reports a longitudinal safety monitoring of popular HuggingFace LLMs.
Read the full abstract ▾
All authors Zhen Sun, Zongmin Zhang, Deqi Liang, Han Sun, Yule Liu, Yun Shen, Xiangshan Gao, Yilong Yang, Shuai Liu, Yutao Yue, Xinlei He
Cryptography and Security
Q-MLLM: Vector Quantization for Robust Multimodal Large Language Model Security
Wei Zhao, Zhe Li, Yige Li et al. (+1 more)
Multimodal Large
Language Models (MLLMs) have demonstrated impressive capabilities in cross-modal understanding, but remain vulnerable to
adversarial attacks through visual inputs despite robust textual safety mechanisms. These vulnerabilities arise from two core weaknesses: the continuous nature of visual representations, which allows for gradient-based attacks, and the inadequate transfer of text-based safety mechanisms to visual content. We introduce Q-MLLM, a novel architecture that integrates two-level vector quantization to create a discrete bottleneck against
adversarial attacks while preserving
multimodal reasoning capabilities. By discretizing visual representations at both pixel-patch and semantic levels, Q-MLLM blocks attack pathways and bridges the cross-modal safety
alignment gap. Our two-stage training methodology ensures robust learning while maintaining model utility. Experiments demonstrate that Q-MLLM achieves significantly better defense success rate against both jailbreak attacks and toxic image attacks than existing approaches. Notably, Q-MLLM achieves perfect defense success rate (100%) against jailbreak attacks except in one arguable case, while maintaining competitive performance on multiple utility
benchmarks with minimal inference overhead. This work establishes vector quantization as an effective defense mechanism for secure
multimodal AI systems without requiring expensive safety-specific fine-tuning or detection overhead. Code is available at https://github.com/Amadeuszhao/QMLLM.
Read the full abstract ▾
All authors Wei Zhao, Zhe Li, Yige Li, Jun Sun
Cryptography and Security
PSM: Prompt Sensitivity Minimization via LLM-Guided Black-Box Optimization
Huseein Jawad and Nicolas Brunel
System
prompts are critical for guiding the behavior of Large
Language Models (LLMs), yet they often contain proprietary logic or sensitive information, making them a
prime target for extraction attacks.
Adversarial queries can successfully elicit these hidden instructions, posing significant security and
privacy risks. Existing defense mechanisms frequently rely on heuristics, incur substantial computational overhead, or are inapplicable to models accessed via black-box APIs. This paper introduces a novel framework for hardening system
prompts through shield appending, a lightweight approach that adds a protective textual layer to the original
prompt. Our core contribution is the formalization of
prompt hardening as a utility-constrained optimization problem. We leverage an LLM-as-optimizer to search the space of possible SHIELDs, seeking to minimize a leakage metric derived from a suite of
adversarial attacks, while simultaneously preserving task utility above a specified threshold, measured by semantic fidelity to baseline outputs. This black-box, optimization-driven methodology is lightweight and practical, requiring only API access to the target and optimizer LLMs. We demonstrate empirically that our optimized SHIELDs significantly reduce
prompt leakage against a comprehensive set of extraction attacks, outperforming established baseline defenses without compromising the model's intended functionality. Our work presents a paradigm for developing robust, utility-aware defenses in the escalating landscape of LLM security. The code is made public on the following link: https://github.com/psm-defense/psm
Read the full abstract ▾
Cryptography and Security
ART: A Graph-based Framework for Investigating Illicit Activity in Monero via Address-Ring-Transaction Structures
Andrea Venturi, Imanol Jerico-Yoldi, Francesco Zola et al. (+1 more)
As Law Enforcement Agencies advance in cryptocurrency forensics, criminal actors aiming to conceal illicit fund movements increasingly turn to "mixin" services or
privacy-based cryptocurrencies. Monero stands out as a leading choice due to its strong
privacy preserving and untraceability properties, making conventional blockchain analysis ineffective. Understanding the behavior and operational patterns of criminal actors within Monero is therefore challenging and it is essential to support future investigative strategies and disrupt illicit activities. In this work, we propose a case study in which we leverage a novel graph-based methodology to extract structural and temporal patterns from Monero transactions linked to already discovered criminal activities. By building Address-Ring-Transaction graphs from flagged transactions, we extract structural and temporal features and use them to train Machine Learning models capable of detecting similar behavioral patterns that could highlight criminal modus operandi. This represents a first partial step toward developing analytical tools that support investigative efforts in
privacy-preserving blockchain ecosystems
Read the full abstract ▾
All authors Andrea Venturi, Imanol Jerico-Yoldi, Francesco Zola, Raul Orduna
Cryptography and Security
Multi-Faceted Attack: Exposing Cross-Model Vulnerabilities in Defense-Equipped Vision-Language Models
Yijun Yang, Lichao Wang, Jianping Zhang et al. (+3 more)
The growing misuse of
Vision-
Language Models (VLMs) has led providers to deploy multiple safeguards, including
alignment tuning, system
prompts, and content moderation. However, the real-world robustness of these defenses against
adversarial attacks remains underexplored. We introduce Multi-Faceted Attack (MFA), a framework that systematically exposes general safety vulnerabilities in leading defense-equipped VLMs such as GPT-4o, Gemini-Pro, and Llama-4. The core component of MFA is the
Attention-Transfer Attack (ATA), which hides harmful instructions inside a meta task with competing objectives. We provide a theoretical perspective based on reward hacking to explain why this attack succeeds. To improve cross-model transferability, we further introduce a lightweight transfer-enhancement
algorithm combined with a simple repetition strategy that jointly bypasses both input-level and output-level filters without model-specific fine-tuning. Empirically, we show that
adversarial images optimized for one
vision encoder transfer broadly to unseen VLMs, indicating that shared visual representations create a cross-model safety vulnerability. Overall, MFA achieves a 58.5% success rate and consistently outperforms existing methods. On state-of-the-art commercial models, MFA reaches a 52.8% success rate, surpassing the second-best attack by 34%. These results challenge the perceived robustness of current defense mechanisms and highlight persistent safety weaknesses in modern VLMs. Code: https://github.com/cure-lab/MultiFacetedAttack
Read the full abstract ▾
All authors Yijun Yang, Lichao Wang, Jianping Zhang, Chi Harold Liu, Lanqing Hong, Qiang Xu
Cryptography and Security
Future-Back Threat Modeling: A Foresight-Driven Security Framework
Vu Van Than
Traditional threat modeling remains reactive-focused on known TTPs and past incident data, while threat prediction and
forecasting frameworks are often disconnected from operational or architectural artifacts. This creates a fundamental weakness: the most serious cyber threats often do not arise from what is known, but from what is assumed, overlooked, or not yet conceived, and frequently originate from the future, such as artificial intelligence, information warfare, and supply chain attacks, where adversaries continuously develop new exploits that can bypass defenses built on current knowledge. To address this mental gap, this paper introduces the theory and methodology of Future-Back Threat Modeling (FBTM). This predictive approach begins with envisioned future threat states and works backward to identify assumptions, gaps, blind spots, and vulnerabilities in the current defense architecture, providing a clearer and more accurate view of impending threats so that we can anticipate their emergence and shape the future we want through actions taken now. The proposed methodology further aims to reveal known unknowns and unknown unknowns, including tactics, techniques, and procedures that are emerging, anticipated, and plausible. This enhances the predictability of adversary behavior, particularly under future uncertainty, helping security leaders make informed decisions today that shape more resilient security postures for the future.
Read the full abstract ▾
Cryptography and Security
A Quantum-Secure and Blockchain-Integrated E-Voting Framework with Identity Validation
Ashwin Poudel, Utsav Poudel, Dikshyanta Aryal et al. (+3 more)
The rapid growth of
quantum computing poses a threat to the cryptographic foundations of digital systems, requiring the development of secure and scalable electronic voting (evoting) frameworks. We introduce a post-
quantum-secure evoting architecture that integrates Falcon
lattice-based digital signatures, biometric authentication via MobileNetV3 and AdaFace, and a permissioned blockchain for tamper-proof vote storage. Voter registration involves capturing facial
embeddings, which are digitally signed using Falcon and stored on-chain to ensure integrity and non-repudiation. During voting, real-time biometric verification is performed using anti-spoofing techniques and cosine-similarity matching. The system demonstrates low latency and robust spoof detection, monitored through Prometheus and Grafana for real-time
auditing. The average classification error rates (ACER) are below 3.5% on the CelebA Spoof
dataset and under 8.2% on the Wild Face Anti-Spoofing (WFAS)
dataset. Blockchain anchoring incurs minimal gas overhead, approximately 3.3% for registration and 0.15% for voting, supporting system efficiency, auditability, and transparency. The experimental results confirm the system's scalability, efficiency, and resilience under concurrent loads. This approach offers a unified solution to address key challenges in voter authentication, data integrity, and
quantum-resilient security for digital systems.
Read the full abstract ▾
All authors Ashwin Poudel, Utsav Poudel, Dikshyanta Aryal, Anuj Nepal, Pranish Pathak, Subramaniyaswamy V
Cryptography and Security · Cross-listed from quant-ph
Nonadaptive One-Way to Hiding Implies Adaptive Quantum Reprogramming
Joseph Jaeger
An important proof technique in the random oracle model involves reprogramming it on hard to predict inputs and arguing that an attacker cannot detect that this occurred. In the
quantum setting, a particularly challenging version of this considers adaptive reprogramming wherein the points to be reprogrammed (or the output values they should be programmed to) are dependent on choices made by the adversary. Some
quantum frameworks for analyzing adaptive reprogramming were given by Unruh (CRYPTO 2014, EUROCRYPT 2015), Grilo-Hövelmanns-Hülsing-Majenz (ASIACRYPT 2021), and Pan-Zeng (PKC 2024). We show, counterintuitively, that these adaptive results follow from the nonadaptive one-way to hiding
theorem of Ambainis-Hamburg-Unruh (CRYPTO 2019). These implications contradict beliefs (whether stated explicitly or implicitly) that some properties of the adaptive frameworks cannot be provided by the Ambainis-Hamburg-Unruh result.
Read the full abstract ▾
Cryptography and Security
Hiding in the AI Traffic: Abusing MCP for LLM-Powered Agentic Red Teaming
Strahinja Janjusevic, Anna Baron Garcia and Sohrob Kazerounian
Generative AI is reshaping offensive cybersecurity by enabling autonomous red team
agents that can plan, execute, and adapt during penetration tests. However, existing approaches face trade-offs between generality and specialization, and practical deployments reveal challenges such as
hallucinations, context limitations, and ethical concerns. In this work, we introduce a novel command & control (C2) architecture leveraging the Model Context Protocol (MCP) to coordinate distributed, adaptive reconnaissance
agents covertly across networks. Notably, we find that our architecture not only improves goal-directed behavior of the system as whole, but also eliminates key host and network artifacts that can be used to detect and prevent command & control behavior altogether. We begin with a comprehensive review of state-of-the-art generative red teaming methods, from fine-tuned specialist models to modular or agentic frameworks, analyzing their automation capabilities against task-specific accuracy. We then detail how our MCP-based C2 can overcome current limitations by enabling asynchronous, parallel operations and real-time intelligence sharing without periodic beaconing. We furthermore explore advanced
adversarial capabilities of this architecture, its detection-evasion techniques, and address dual-use ethical implications, proposing defensive measures and controlled evaluation in lab settings. Experimental comparisons with traditional C2 show drastic reductions in manual effort and detection footprint. We conclude with future directions for integrating autonomous exploitation, defensive LLM
agents, predictive evasive maneuvers, and multi-
agent swarms. The proposed MCP-enabled C2 framework demonstrates a significant step toward realistic, AI-driven red team operations that can simulate advanced persistent threats while informing the development of next-generation defensive systems.
Read the full abstract ▾
Cryptography and Security
Digital Agriculture Sandbox for Collaborative Research
Osama Zafar, Rosemarie Santa González, Alfonso Morales et al. (+1 more)
Digital agriculture is transforming the way we grow food by utilizing technology to make farming more efficient, sustainable, and productive. This modern approach to agriculture generates a wealth of valuable data that could help address global food challenges, but farmers are hesitant to share it due to
privacy concerns. This limits the extent to which researchers can learn from this data to inform improvements in farming. This paper presents the Digital Agriculture Sandbox, a secure online platform that solves this problem. The platform enables farmers (with limited technical resources) and researchers to collaborate on analyzing farm data without exposing private information. We employ specialized techniques such as
federated learning, differential
privacy, and data analysis methods to safeguard the data while maintaining its utility for research purposes. The system enables farmers to identify similar farmers in a simplified manner without needing extensive technical knowledge or access to computational resources. Similarly, it enables researchers to learn from the data and build helpful tools without the sensitive information ever leaving the farmer's system. This creates a safe space where farmers feel comfortable sharing data, allowing researchers to make important discoveries. Our platform helps bridge the gap between maintaining farm data
privacy and utilizing that data to address critical food and farming challenges worldwide.
Read the full abstract ▾
All authors Osama Zafar, Rosemarie Santa González, Alfonso Morales, Erman Ayday
Cryptography and Security · Cross-listed from math.RT
Representations of Cyclic Diagram Monoids
Jason Liu
We introduce cyclic diagram monoids, a generalisation of classical diagram monoids that adds elements of arbitrary period by including internal components, with a view towards cryptography. We classify their simple representations and compute their dimensions in terms of the underlying diagram
algebra. These go towards showing that cyclic diagram monoids possess representation gaps of exponential growth, which quantify their resistance as platforms against linear attacks on cryptographic protocols that exploit small dimensional representations.
Read the full abstract ▾
Cryptography and Security
Lifefin: Escaping Mempool Explosions in DAG-based BFT
Jianting Zhang, Sen Yang, Alberto Sonnino et al. (+2 more)
Directed Acyclic Graph (DAG)-based Byzantine Fault-Tolerant (BFT) protocols have emerged as promising solutions for high-throughput blockchains. By decoupling data dissemination from transaction ordering and constructing a well-connected DAG in the mempool, these protocols enable zero-message ordering and implicit view changes. However, we identify a fundamental liveness vulnerability: an adversary can trigger mempool explosions to prevent transaction commitment, ultimately compromising the protocol's liveness. In response, this work presents Lifefin, a generic and self-stabilizing protocol designed to integrate seamlessly with existing DAG-based BFT protocols and circumvent such vulnerabilities. Lifefin leverages the Agreement on Common Subset (ACS) mechanism, allowing nodes to escape mempool explosions by committing transactions with bounded resource usage even in adverse conditions. As a result, Lifefin imposes (almost) zero overhead in typical cases while effectively eliminating liveness vulnerabilities. To demonstrate the effectiveness of Lifefin, we integrate it into two state-of-the-art DAG-based BFT protocols, Sailfish and Mysticeti, resulting in two enhanced variants: Sailfish-Lifefin and Mysticeti-Lifefin. We implement these variants and compare them with the original Sailfish and Mysticeti systems. Our evaluation demonstrates that Lifefin achieves comparable transaction throughput while introducing only minimal additional latency to resist similar attacks.
Read the full abstract ▾
All authors Jianting Zhang, Sen Yang, Alberto Sonnino, Sebastián Loza, Aniket Kate