Cryptography and Security · Cross-listed from cs.IT
Secure Multi-User Linearly-Separable Distributed Computing
Amir Masoud Jafarpisheh, Ali Khalesi and Petros Elia
The introduction of the new multi-user linearly-separable distributed computing framework, has recently revealed how a parallel treatment of users can yield large parallelization gains with relatively low computation and communication costs. These gains stem from a new approach that converts the computing problem into a sparse
matrix factorization problem; a
matrix \(\mathbf{F}\) that describes the users' requests, is decomposed as \(\mathbf{F} = \mathbf{DE}\), where a \(\gamma\)-sparse \(\mathbf{E}\) defines the task allocation across \(N\) servers, and a \(\delta\)-sparse \(\mathbf{D}\) defines the connectivity between \(N\) servers and \(K\) users as well as the decoding process. While this approach provides near-optimal performance, its linear nature has raised data secrecy concerns. We adopt an information-theoretic secrecy framework requiring that each user learns nothing more than its own requested function. Our main results provide (i) a necessary condition stating that for each user $k$ observing \(\alpha_k\) server responses, the common randomness visible to that user must span a subspace of dimension greater than \(\alpha_k-1\), and (ii) a necessary and sufficient condition requiring that removing from \(\mathbf{D}\) the columns corresponding to the servers observed by a user leaves a
matrix of rank at least \(K-1\). Based on these conditions, we design a general, cost-preserving secrecy-enforcing transformation valid over both finite and real fields, obtained by appending to \(\mathbf{E}\) a basis of \(\mathrm{Null}(\mathbf{D})\) and carefully injecting shared randomness. This scheme preserves communication and computation costs, guarantees perfect information-theoretic secrecy over finite fields, and in the real case yields an explicit mutual-information bound that can be made arbitrarily small by increasing the variance of Gaussian common randomness.
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Cryptography and Security
Provenance Verification of AI-Generated Images via a Perceptual Hash Registry Anchored on Blockchain
Apoorv Mohit, Bhavya Aggarwal and Chinmay Gondhalekar
The rapid advancement of artificial intelligence has made the generation of synthetic images widely accessible, increasing concerns related to misinformation, digital forgery, and content authenticity on large-scale online platforms. This paper proposes a blockchain-backed framework for verifying AI-generated images through a registry-based provenance mechanism. Each AI-generated image is assigned a digital fingerprint that preserves similarity using perceptual hashing and is registered at creation time by participating generation platforms. The hashes are stored on a hybrid on-chain/off-chain public blockchain using a Merkle Patricia Trie for tamper-resistant storage (on-chain) and a Burkhard-Keller tree (off-chain) to enable efficient similarity search over large image registries. Verification is performed when images are re-uploaded to digital platforms such as social media services, enabling identification of previously registered AI-generated images even after benign transformations or partial modifications. The proposed system does not aim to universally detect all synthetic images, but instead focuses on verifying the provenance of AI-generated content that has been registered at creation time. By design, this approach complements existing watermarking and learning-based detection methods, providing a platform-agnostic, tamper-proof mechanism for scalable content provenance and authenticity verification at the point of large-scale online distribution.
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Cryptography and Security · Cross-listed from cs.LG
David vs. Goliath: Verifiable Agent-to-Agent Jailbreaking via Reinforcement Learning
Samuel Nellessen and Tal Kachman
The
evolution of large
language models into autonomous
agents introduces
adversarial failures that exploit legitimate tool privileges, transforming safety evaluation in tool-augmented environments from a subjective NLP task into an objective control problem. We formalize this threat model as Tag-Along Attacks: a scenario where a tool-less adversary "tags along" on the trusted privileges of a safety-aligned Operator to induce prohibited tool use through conversation alone. To validate this threat, we present Slingshot, a 'cold-start' reinforcement learning framework that autonomously discovers emergent attack vectors, revealing a critical insight: in our setting, learned attacks tend to converge to short, instruction-like syntactic patterns rather than multi-turn persuasion. On held-out extreme-difficulty tasks, Slingshot achieves a 67.0% success rate against a Qwen2.5-32B-Instruct-AWQ Operator (vs. 1.7% baseline), reducing the expected attempts to first success (on solved tasks) from 52.3 to 1.3. Crucially, Slingshot transfers zero-shot to several model families, including closed-source models like Gemini 2.5 Flash (56.0% attack success rate) and defensive-fine-tuned open-source models like Meta-SecAlign-8B (39.2% attack success rate). Our work establishes Tag-Along Attacks as a first-class, verifiable threat model and shows that effective agentic attacks can be elicited from off-the-shelf open-weight models through environment interaction alone.
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Cryptography and Security · Cross-listed from quant-ph
Guaranteeing Privacy in Hybrid Quantum Learning through Theoretical Mechanisms
Hoang M. Ngo, Tre' R. Jeter, Incheol Shin et al. (+3 more)
Quantum Machine Learning (QML) is becoming increasingly prevalent due to its potential to enhance classical machine learning (ML) tasks, such as classification. Although
quantum noise is often viewed as a major challenge in
quantum computing, it also offers a unique opportunity to enhance
privacy. In particular, intrinsic
quantum noise provides a natural
stochastic resource that, when rigorously analyzed within the differential
privacy (DP) framework and composed with classical mechanisms, can satisfy formal $(\varepsilon, \delta)$-DP guarantees. This enables a reduction in the required classical perturbation without compromising the
privacy budget, potentially improving model utility. However, the integration of classical and
quantum noise for
privacy preservation remains unexplored. In this work, we propose a hybrid noise-added mechanism, HYPER-Q, that combines classical and
quantum noise to protect the
privacy of QML models. We provide a comprehensive analysis of its
privacy guarantees and establish theoretical bounds on its utility. Empirically, we demonstrate that HYPER-Q outperforms existing classical noise-based mechanisms in terms of
adversarial robustness across multiple real-world
datasets.
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All authors Hoang M. Ngo, Tre' R. Jeter, Incheol Shin, Wanli Xing, Tamer Kahveci, My T. Thai
Cryptography and Security · Cross-listed from cs.LG
Decoupling Generalizability and Membership Privacy Risks in Neural Networks
Xingli Fang and Jung-Eun Kim
A deep learning model usually has to sacrifice some utilities when it acquires some other abilities or characteristics.
Privacy preservation has such trade-off relationships with utilities. The loss disparity between various defense approaches implies the potential to decouple generalizability and
privacy risks to maximize
privacy gain. In this paper, we identify that the model's generalization and
privacy risks exist in different regions in deep neural network architectures. Based on the observations that we investigate, we propose
Privacy-Preserving Training Principle (PPTP) to protect model components from
privacy risks while minimizing the loss in generalizability. Through extensive evaluations, our approach shows significantly better maintenance in model generalizability while enhancing
privacy preservation.
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Cryptography and Security · Cross-listed from cs.SE
RACC: Representation-Aware Coverage Criteria for LLM Safety Testing
Zeming Wei, Zhixin Zhang, Chengcan Wu et al. (+3 more)
Large
Language Models (LLMs) face severe safety risks from jailbreak attacks, yet current safety testing largely relies on static
datasets and lacks systematic criteria to evaluate test suite quality and adequacy. While coverage criteria have proven effective for smaller neural networks, they are impractical for LLMs due to computational overhead and the
entanglement of safety-critical signals with irrelevant
neuron activations. To address these issues, we propose RACC (Representation-Aware Coverage Criteria), a set of coverage criteria specialized for LLM safety testing. RACC first extracts safety representations from the LLM's hidden states using a small calibration set of harmful
prompts, then measures test
prompts' concept activations against these directions, and finally computes coverage through six criteria assessing both individual and compositional safety concept coverage. Experiments on multiple LLMs and safety
benchmarks show that RACC reliably rewards high-quality jailbreak test suites while remaining insensitive to redundant or invalid inputs, which is a key distinction that
neuron-level criteria fail to make. We further demonstrate RACC's practical value in two applications, including test suite prioritization and attack
prompt sampling, and validate its generalization across diverse settings and configurations. Overall, RACC provides a scalable and principled foundation for coverage-guided LLM safety testing.
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All authors Zeming Wei, Zhixin Zhang, Chengcan Wu, Yihao Zhang, Xiaokun Luan, Meng Sun
Cryptography and Security
SysFuSS: System-Level Firmware Fuzzing with Selective Symbolic Execution
Dakshina Tharindu, Aruna Jayasena and Prabhat Mishra
Firmware serves as the critical interface between hardware and software in computing systems, making any bugs or vulnerabilities particularly dangerous as they can cause catastrophic system failures. While fuzzing is a promising approach for identifying design flaws and security vulnerabilities, traditional fuzzers are ineffective at detecting firmware vulnerabilities. For example, existing fuzzers focus on user-level fuzzing, which is not suitable for detecting kernel-level vulnerabilities. Existing fuzzers also face a coverage plateau problem when dealing with complex interactions between firmware and hardware. In this paper, we present an efficient firmware verification framework, SysFuSS, that integrates system-level fuzzing with selective symbolic execution. Our approach leverages system-level emulation for initial fuzzing, and automatically transitions to symbolic execution when coverage reaches a plateau. This strategy enables us to generate targeted test cases that can trigger previously unexplored regions in firmware designs. We have evaluated SysFuSS on real-world embedded firmware, including OpenSSL, WolfBoot, WolfMQTT, HTSlib, MXML, and libIEC. Experimental evaluation demonstrates that SysFuSS significantly outperforms state-of-the-art fuzzers in terms of both branch coverage and detection of firmware vulnerabilities. Specifically, SysFuSS can detect 118 known vulnerabilities while state-of-the-art can cover only 13 of them. Moreover, SysFuSS takes significantly less time (up to 3.3X, 1.7X on average) to activate these vulnerabilities.
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Cryptography and Security · Cross-listed from cs.CV
MIRROR: Manifold Ideal Reference ReconstructOR for Generalizable AI-Generated Image Detection
Ruiqi Liu, Manni Cui, Ziheng Qin et al. (+12 more)
High-fidelity generative models have narrowed the perceptual gap between synthetic and real images, posing serious threats to media security. Most existing AI-generated image (AIGI) detectors rely on artifact-based classification and struggle to generalize to evolving generative traces. In contrast, human judgment relies on stable real-world regularities, with deviations from the human cognitive
manifold serving as a more generalizable signal of forgery. Motivated by this insight, we reformulate AIGI detection as a Reference-Comparison problem that verifies consistency with the real-image
manifold rather than fitting specific forgery cues. We propose MIRROR (
Manifold Ideal Reference ReconstructOR), a framework that explicitly encodes reality priors using a learnable discrete
memory bank. MIRROR projects an input into a
manifold-consistent ideal reference via sparse linear combination, and uses the resulting residuals as robust detection signals. To evaluate whether detectors reach the "superhuman crossover" required to replace human experts, we introduce the Human-AIGI
benchmark, featuring a psychophysically curated human-imperceptible subset. Across 14
benchmarks, MIRROR consistently outperforms prior methods, achieving gains of 2.1% on six standard
benchmarks and 8.1% on seven in-the-wild
benchmarks. On Human-AIGI, MIRROR reaches 89.6% accuracy across 27 generators, surpassing both lay users and visual experts, and further approaching the human perceptual limit as pretrained backbones scale. The code is publicly available at: https://github.com/349793927/MIRROR
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All authors Ruiqi Liu, Manni Cui, Ziheng Qin, Zhiyuan Yan, Ruoxin Chen, Yi Han, Zhiheng Li, Junkai Chen, ZhiJin Chen, Kaiqing Lin, Jialiang Shen, Lubin Weng, Jing Dong, Yan Wang, Shu Wu
Cryptography and Security
QuietPrint: Protecting 3D Printers Against Acoustic Side-Channel Attacks
Seyed Ali Ghazi Asgar and Narasimha Reddy
The 3D printing
market has experienced significant growth in recent years, with an estimated revenue of 15 billion USD for 2025. Cyber-attacks targeting the 3D printing process whether through the machine itself, the supply chain, or the fabricated components are becoming increasingly common. One major concern is intellectual property (IP) theft, where a malicious attacker gains access to the design file. One method for carrying out such theft is through side-channel attacks. In this work, we investigate the possibility of IP theft via acoustic side channels and propose a novel method to protect 3D printers against such attacks. The primary advantage of our approach is that it requires no additional hardware, such as large speakers or noise-canceling devices. Instead, it secures printed parts by minimal modifications to the G-code.
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Cryptography and Security
Malware Detection Through Memory Analysis
Sarah Nassar
This paper summarizes the research conducted for a malware detection project using the Canadian Institute for Cybersecurity's MalMemAnalysis-2022
dataset. The purpose of the project was to explore the effectiveness and efficiency of machine learning techniques for the task of binary classification (i.e., benign or malicious) as well as multi-class classification to further include three malware sub-types (i.e., benign, ransomware, spyware, or Trojan horse). The XGBoost model type was the final model selected for both tasks due to the trade-off between strong detection capability and fast inference speed. The binary classifier achieved a testing subset accuracy and F1 score of 99.98%, while the multi-class version reached an accuracy of 87.54% and an F1 score of 81.26%, with an average F1 score over the malware sub-types of 75.03%. In addition to the high modelling performance, XGBoost is also efficient in terms of classification speed. It takes about 37.3 milliseconds to classify 50 samples in sequential order in the binary setting and about 43.2 milliseconds in the multi-class setting. The results from this research project help advance the efforts made towards developing accurate and real-time obfuscated malware detectors for the goal of improving online
privacy and safety. *This project was completed as part of ELEC 877 (AI for Cybersecurity) in the Winter 2024 term.
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Cryptography and Security · Cross-listed from cs.LG
Co-RedTeam: Orchestrated Security Discovery and Exploitation with LLM Agents
Pengfei He, Ash Fox, Lesly Miculicich et al. (+7 more)
Large
language models (LLMs) have shown promise in assisting cybersecurity tasks, yet existing approaches struggle with automatic vulnerability discovery and exploitation due to limited interaction, weak execution grounding, and a lack of experience reuse. We propose Co-RedTeam, a security-aware multi-
agent framework designed to mirror real-world red-teaming workflows by integrating security-domain knowledge, code-aware analysis, execution-grounded iterative
reasoning, and long-term
memory. Co-RedTeam decomposes vulnerability analysis into coordinated discovery and exploitation stages, enabling
agents to plan, execute, validate, and refine actions based on real execution feedback while learning from prior trajectories. Extensive evaluations on challenging security
benchmarks demonstrate that Co-RedTeam consistently outperforms strong baselines across diverse backbone models, achieving over 60% success rate in vulnerability exploitation and over 10% absolute improvement in vulnerability detection. Ablation and iteration studies further confirm the critical role of execution feedback, structured interaction, and
memory for building robust and generalizable cybersecurity
agents.
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All authors Pengfei He, Ash Fox, Lesly Miculicich, Stefan Friedli, Daniel Fabian, Burak Gokturk, Jiliang Tang, Chen-Yu Lee, Tomas Pfister, Long T. Le
Cryptography and Security
HPE: Hallucinated Positive Entanglement for Backdoor Attacks in Federated Self-Supervised Learning
Jiayao Wang, Yang Song, Zhendong Zhao et al. (+5 more)
Federated self-supervised learning (FSSL) enables collaborative training of self-supervised representation models without sharing raw unlabeled data. While it serves as a crucial paradigm for
privacy-preserving learning, its security remains vulnerable to
backdoor attacks, where malicious clients manipulate local training to inject targeted
backdoors. Existing FSSL attack methods, however, often suffer from low utilization of poisoned samples, limited transferability, and weak persistence. To address these limitations, we propose a new
backdoor attack method for FSSL, namely Hallucinated Positive
Entanglement (HPE). HPE first employs
hallucination-based augmentation using synthetic positive samples to enhance the encoder's
embedding of
backdoor features. It then introduces feature
entanglement to enforce tight binding between triggers and
backdoor samples in the representation space. Finally, selective parameter poisoning and proximity-aware updates constrain the poisoned model within the vicinity of the global model, enhancing its stability and persistence. Experimental results on several FSSL scenarios and
datasets show that HPE significantly outperforms existing
backdoor attack methods in performance and exhibits strong robustness under various defense mechanisms.
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All authors Jiayao Wang, Yang Song, Zhendong Zhao, Jiale Zhang, Qilin Wu, Wenliang Yuan, Junwu Zhu, Dongfang Zhao
Cryptography and Security
Human Society-Inspired Approaches to Agentic AI Security: The 4C Framework
Alsharif Abuadbba, Nazatul Sultan, Surya Nepal et al. (+1 more)
AI is moving from domain-specific autonomy in closed, predictable settings to large-
language-model-driven
agents that plan and act in open, cross-organizational environments. As a result, the cybersecurity risk landscape is changing in fundamental ways. Agentic AI systems can plan, act, collaborate, and persist over time, functioning as participants in complex socio-technical ecosystems rather than as isolated software components. Although recent work has strengthened defenses against model and pipeline level vulnerabilities such as
prompt injection, data poisoning, and tool misuse, these system centric approaches may fail to capture risks that arise from autonomy, interaction, and emergent behavior. This article introduces the 4C Framework for multi-
agent AI security, inspired by societal governance. It organizes agentic risks across four interdependent dimensions: Core (system, infrastructure, and environmental integrity), Connection (communication, coordination, and trust), Cognition (belief, goal, and
reasoning integrity), and Compliance (ethical, legal, and institutional governance). By shifting AI security from a narrow focus on system-centric protection to the broader preservation of behavioral integrity and intent, the framework complements existing AI security strategies and offers a principled foundation for building agentic AI systems that are trustworthy, governable, and aligned with human values.
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All authors Alsharif Abuadbba, Nazatul Sultan, Surya Nepal, Sanjay Jha
Cryptography and Security
Things that Matter – Identifying Interactions and IoT Device Types in Encrypted Matter Traffic
Kristopher Alex Schlett, Bela Genge, Ioan Padurean et al. (+1 more)
Matter is the most recent application-layer standard for the Internet of Things (IoT). As one of its major selling points, Matter's design imposes particular
attention to security and
privacy: it provides validated secure session establishment protocols, and it uses robust security
algorithms to secure communications between IoT devices and Matter controllers. However, to our knowledge, there is no systematic analysis investigating the extent to which a passive attacker, in possession of lower layer keys or exploiting security misconfiguration at those layers, could infer information by passively analyzing encrypted Matter traffic. In this paper, we fill this gap by analyzing the robustness of the Matter IoT standard to encrypted traffic analysis performed by a passive eavesdropper. By using various
datasets collected from real-world testbeds and simulated setups, we identify patterns in metadata of the encrypted Matter traffic that allow inferring the specific interactions occurring between end devices and controllers. Moreover, we associate patterns in sequences of interactions to specific types of IoT devices. These patterns can be used to create fingerprints that allow a passive attacker to infer the type of devices used in the network, constituting a serious breach of users
privacy. Our results reveal that we can identify specific Matter interactions that occur in encrypted traffic with over $95\%$ accuracy also in the presence of packet losses and delays. Moreover, we can identify Matter device types with a minimum accuracy of $88\%$. The CSA acknowledged our findings, and expressed the willingness to address such vulnerabilities in the next releases of the standard.
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All authors Kristopher Alex Schlett, Bela Genge, Ioan Padurean, Savio Sciancalepore
Cryptography and Security · Cross-listed from cs.HC
When Feasibility of Fairness Audits Relies on Willingness to Share Data: Examining User Acceptance of Multi-Party Computation Protocols for Fairness Monitoring
Changyang He, Parnian Jahangirirad, Lin Kyi et al. (+1 more)
Fairness monitoring is critical for detecting algorithmic bias, as mandated by the EU AI Act. Since such monitoring requires sensitive user data (e.g., ethnicity), the AI Act permits its processing only with strict
privacy measures, such as multi-party computation (MPC), in compliance with the GDPR. However, the effectiveness of such secure monitoring protocols ultimately depends on people's willingness to share their data. Little is known about how different MPC protocol designs shape user acceptance. To address this, we conducted an online survey with 833 participants in Europe, examining user acceptance of various MPC protocol designs for
fairness monitoring. Findings suggest that users prioritized risk-related attributes (e.g.,
privacy protection mechanism) in direct evaluation but benefit-related attributes (e.g.,
fairness objective) in simulated choices, with acceptance shaped by their
fairness and
privacy orientations. We derive implications for deploying and communicating
privacy-preserving protocols in ways that foster informed consent and align with user expectations.
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All authors Changyang He, Parnian Jahangirirad, Lin Kyi, Asia J. Biega
Cryptography and Security · Cross-listed from cs.CY
Co-designing for Compliance: Multi-party Computation Protocols for Post-Market Fairness Monitoring in Algorithmic Hiring
Changyang He, Nina Baranowska, Josu Andoni Eguiluz Castaneira et al. (+5 more)
Post-
market fairness monitoring is now mandated to ensure
fairness and accountability for high-risk employment AI systems under emerging regulations such as the EU AI Act. However, effective
fairness monitoring often requires access to sensitive personal data, which is subject to strict legal protections under data protection law. Multi-party computation (MPC) offers a promising technical foundation for compliant post-
market fairness monitoring, enabling the secure computation of
fairness metrics without revealing sensitive attributes. Despite growing technical interest, the operationalization of MPC-based
fairness monitoring in real-world hiring contexts under concrete legal, industrial, and usability constraints remains unknown. This work addresses this gap through a co-design approach integrating technical, legal, and industrial expertise. We identify practical design requirements for MPC-based
fairness monitoring, develop an end-to-end, legally compliant protocol spanning the full data lifecycle, and empirically validate it in a large-scale industrial setting. Our findings provide actionable design insights as well as legal and industrial implications for deploying MPC-based post-
market fairness monitoring in algorithmic hiring systems.
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All authors Changyang He, Nina Baranowska, Josu Andoni Eguiluz Castaneira, Guillem Escriba, Matthias Juentgen, Anna Via, Frederik Zuiderveen Borgesius, Asia Biega
Cryptography and Security
RedVisor: Reasoning-Aware Prompt Injection Defense via Zero-Copy KV Cache Reuse
Mingrui Liu, Sixiao Zhang, Cheng Long et al. (+1 more)
Large
Language Models (LLMs) are increasingly vulnerable to
Prompt Injection (PI) attacks, where
adversarial instructions hidden within retrieved contexts hijack the model's execution flow. Current defenses typically face a critical trade-off: prevention-based fine-tuning often degrades general utility via the "
alignment tax", while detection-based filtering incurs prohibitive latency and
memory costs. To bridge this gap, we propose RedVisor, a unified framework that synthesizes the explainability of detection systems with the seamless integration of prevention strategies. To the best of our knowledge, RedVisor is the first approach to leverage fine-grained
reasoning paths to simultaneously detect attacks and guide the model's safe response. We implement this via a lightweight, removable adapter positioned atop the frozen backbone. This adapter serves a dual function: it first generates an explainable analysis that precisely localizes the injection and articulates the threat, which then explicitly conditions the model to reject the malicious command. Uniquely, the adapter is active only during this
reasoning phase and is effectively muted during the subsequent response generation. This architecture yields two distinct advantages: (1) it mathematically preserves the backbone's original utility on benign inputs; and (2) it enables a novel KV Cache Reuse strategy, eliminating the redundant prefill computation inherent to decoupled pipelines. We further pioneer the integration of this defense into the vLLM serving engine with custom kernels. Experiments demonstrate that RedVisor outperforms state-of-the-art defenses in detection accuracy and throughput while incurring negligible utility loss.
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All authors Mingrui Liu, Sixiao Zhang, Cheng Long, Kwok-Yan Lam
Cryptography and Security
Backdoor Sentinel: Detecting and Detoxifying Backdoors in Diffusion Models via Temporal Noise Consistency
Bingzheng Wang, Xiaoyan Gu, Hongbo Xu et al. (+5 more)
Diffusion models have been widely deployed in AIGC services, but their reliance on opaque training data exposes them to
backdoor attacks. In practical
auditing scenarios, auditors are typically unable to access model parameters due to intellectual property protection, making white-box or query-intensive detection impractical. After detection, existing detoxification approaches are trapped in a dilemma between detoxification effectiveness and generation quality for service providers. We reveal Temporal Noise Consistency (TNC), a previously unreported phenomenon in which
backdoor activation disrupts the consistency of noise predictions between adjacent
diffusion timesteps within specific temporal segments, while clean inputs remain stable. Based on this finding, we propose TNC-Defense, a closed-loop framework for gray-box
backdoor detection and model repair. Specifically, TNC-Detect (for auditors) uses inference-stage adjacent-noise statistics to detect
backdoors and precisely localize anomalous timesteps without model-weight access. TNC-Detox (for service providers) utilizes these locations to perform trigger-agnostic, timestep-aware correction of the generation path, suppressing
backdoor behavior while reducing detoxification cost. Across five representative
backdoor attacks and state-of-the-art defenses, TNC-Defense improves the average detection accuracy by $11\%$ with negligible additional overhead, and invalidates an average of $98.5\%$ of triggered samples with only a mild degradation in generation quality. Our code is publicly available at: https://github.com/binzhwang/TNC-Defense.
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All authors Bingzheng Wang, Xiaoyan Gu, Hongbo Xu, Hongcheng Li, Zimo Yu, Jiang Zhou, Weiping Wang, Wu Liu
Cryptography and Security · Cross-listed from cs.CL
WorldCup Sampling for Multi-bit LLM Watermarking
Yidan Wang, Yubing Ren, Yanan Cao et al. (+1 more)
As large
language models (LLMs) generate increasingly human-like text, watermarking has emerged as a promising solution for reliable attribution beyond mere detection. While multi-bit watermarking enables richer provenance encoding, existing approaches typically extend zero-bit watermarking schemes by introducing static logit perturbations and counting-based decoding strategies, which can degrade text quality and compromise decoding robustness as the payload increases. In this paper, we propose WorldCup, a multi-bit watermarking framework for LLMs that models the sampling process as a structured communication channel and embeds message bits through a hierarchical competition mechanism guided by complementary signals. Moreover, WorldCup incorporates
entropy-aware modulation to preserve generation quality and enables robust message recovery via confidence-aware decoding that accounts for
token-level reliability. Comprehensive experiments demonstrate that WorldCup achieves a strong balance across message capacity, detectability, robustness, text quality, and decoding efficiency, consistently outperforming prior baselines. We believe that this work establishes a scalable and principled foundation for future research on multi-bit watermarking in LLMs.
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All authors Yidan Wang, Yubing Ren, Yanan Cao, Li Guo
Cryptography and Security · Cross-listed from cs.HC
AI-Assisted Adaptive Rendering for High-Frequency Security Telemetry in Web Interfaces
Mona Rajhans
Modern cybersecurity platforms must process and display high-frequency telemetry such as network logs, endpoint events, alerts, and policy changes in real time. Traditional rendering techniques based on static pagination or fixed polling intervals fail under volume conditions exceeding hundreds of thousands of events per second, leading to UI freezes, dropped frames, or stale data. This paper presents an AI-assisted adaptive rendering framework that dynamically regulates visual update frequency, prioritizes semantically relevant events, and selectively aggregates lower-priority data using behavior-driven heuristics and lightweight on-device machine learning models. Experimental validation demonstrates a 45-60 percent reduction in rendering overhead while maintaining analyst perception of real-time responsiveness.
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Cryptography and Security
Witnessd: Proof-of-process via Adversarial Collapse
David Condrey
Digital signatures prove key possession, not authorship. An author who generates text with AI, constructs intermediate document states post-hoc, and signs each hash produces a signature chain indistinguishable from genuine composition. We address this gap between cryptographic integrity and process provenance. We introduce proof-of-process, a primitive category for evidence that a physical process, not merely a signing key, produced a digital artifact. Our construction, the jitter seal, injects imperceptible microsecond delays derived via HMAC from a session secret, keystroke ordinal, and cumulative document hash. Valid evidence requires that real keystrokes produced the document through those intermediate states. We propose the
Adversarial Collapse Principle as an evaluation criterion: evidence systems should be judged by whether disputing them requires a conjunction of specific, testable allegations against components with independent trust assumptions. We present Witnessd, an architecture combining jitter seals with Verifiable Delay Functions, external timestamp anchors, dual-source keystroke validation, and optional hardware attestation. Each layer forces allegations at different capability levels; disputing authentic evidence requires coordinated claims across independent trust boundaries. The system does not prevent forgery: a kernel-level adversary can defeat it, and typing AI-generated content produces valid evidence. The contribution is converting vague doubt into falsifiable allegations. We evaluate across 31,000 verification trials with deterministic rejection of invalid proofs.
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Cryptography and Security
CGF-Softmax: A Cumulant-Based Softmax Reformulation for Efficient Inference under Homomorphic Encryption
Hanjun Park, Byeongseo Min, Jiheon Woo et al. (+5 more)
Homomorphic encryption (HE) is a prominent framework for
privacy-preserving machine learning, enabling inference directly on encrypted data. However, evaluating softmax, a core component of
transformer architectures, remains particularly challenging in HE due to its multivariate structure, the large dynamic range induced by exponential functions, and the costly division operation. In this paper, we propose CGF-softmax, which reformulates the softmax denominator through the cumulant generating function (CGF). By eliminating both homomorphic division and explicit maximum subtraction, this reformulation substantially reduces multiplicative depth while preserving key properties of softmax. Extensive experiments on
Vision Transformers and large
language models show that CGF-softmax provides an efficient and accurate approximation of softmax in encrypted inference. In particular, it achieves inference accuracy close to that of high-depth exact methods, while requiring substantially lower computational cost through reduced multiplicative depth.
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All authors Hanjun Park, Byeongseo Min, Jiheon Woo, Min-Wook Jeong, Jongho Shin, Yongwoo Lee, Young-Sik Kim, Yongjune Kim
Cryptography and Security
Expected Harm: Rethinking Safety Evaluation of (Mis)Aligned LLMs
Yen-Shan Chen, Zhi Rui Tam, Cheng-Kuang Wu et al. (+1 more)
Current evaluations of LLM safety predominantly rely on severity-based taxonomies to assess the harmfulness of malicious queries. We argue that this formulation requires re-examination as it assumes uniform risk across all malicious queries, neglecting Execution Likelihood–the conditional probability of a threat being realized given the model's response. In this work, we introduce Expected Harm, a metric that weights the severity of a jailbreak by its execution likelihood, modeled as a function of execution cost. Through empirical analysis of state-of-the-art models, we reveal a systematic Inverse Risk Calibration: models disproportionately exhibit stronger refusal behaviors for low-likelihood (high-cost) threats while remaining vulnerable to high-likelihood (low-cost) queries. We demonstrate that this miscalibration creates a structural vulnerability: by exploiting this property, we increase the attack success rate of existing jailbreaks by up to $2\times$. Finally, we trace the root cause of this failure using linear probing, which reveals that while models encode severity in their latent space to drive refusal decisions, they possess no distinguishable internal representation of execution cost, making them "blind" to this critical dimension of risk.
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All authors Yen-Shan Chen, Zhi Rui Tam, Cheng-Kuang Wu, Yun-Nung Chen
Cryptography and Security · Cross-listed from math.AG
A new criterion for the absolute irreducibility of multivariate polynomials over finite fields
Carlos Agrinsoni, Heeralal Janwa and Moises Delgado
A key property of an algebraic variety is whether it is absolutely irreducible, meaning that it remains irreducible over the algebraic closure of its defining field, and determining absolute irreducibility is important in algebraic geometry and its applications in coding theory, cryptography, and other fields. Among the applications of absolute irreducibility are bounding the number of rational points via the Weil
conjectures and establishing exceptional APN and permutation properties of functions over finite fields. In this article, we present a new criterion for the absolute irreducibility of hypersurfaces defined by multivariate
polynomials over finite fields. Our criterion does not require testing for irreducibility in the ground or extension fields, assuming that the leading form is square-free. We just require multivariate GCD computations and the square-free property. Since almost all
polynomials are known to be square-free, our absolute irreducibility criterion is valid for almost all multivariate
polynomials.
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Cryptography and Security
HACK NDSU: A Real-world Event to Promote Student Interest in Cybersecurity
Enrique Garcia and Jeremy Straub
Hack NDSU let students scan, probe, and hack North Dakota State University's campus network, under professionals' supervision, providing an aspirational experience, potentially motivating them to enter the field. This paper provides a blueprint for educational hacking events against production systems. No prior educational event of this type is known.
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Cryptography and Security
Are Security Cues Static? Rethinking Warning and Trust Indicators for Life Transitions
Sarah Tabassum
Security cues, such as warnings and trust signals, are designed as stable interface elements, even though people's lives, contexts, and vulnerabilities change over time. Life transitions including migration, aging, or shifts in institutional environments reshape how risk and trust are understood and acted upon. Yet current systems rarely adapt their security cues to these changing conditions, placing the burden of interpretation on users. In this Works-in-Progress paper, we argue that the static nature of security cues represents a design mismatch with transitional human lives. We draw on prior empirical insights from work on educational migration as a motivating case, and extend the discussion to other life transitions. Building on these insights, we introduce the Transition-Aware Security Cues (TASeC) framework and present speculative design concepts illustrating how security cues might evolve across transition stages. We invite HCI to rethink security cues as longitudinal, life-centered design elements collectively.
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Cryptography and Security · Cross-listed from eess.IV
MarkCleaner: High-Fidelity Watermark Removal via Imperceptible Micro-Geometric Perturbation
Xiaoxi Kong, Jieyu Yuan, Pengdi Chen et al. (+3 more)
Semantic watermarks exhibit strong robustness against conventional image-space attacks. In this work, we show that such robustness does not survive under micro-
geometric perturbations: spatial displacements can remove watermarks by breaking the phase
alignment. Motivated by this observation, we introduce MarkCleaner, a watermark removal framework that avoids semantic drift caused by regeneration-based watermark removal. Specifically, MarkCleaner is trained with micro-geometry-perturbed supervision, which encourages the model to separate semantic content from strict spatial
alignment and enables robust reconstruction under subtle
geometric displacements. The framework adopts a mask-guided encoder that learns explicit spatial representations and a 2D Gaussian Splatting-based decoder that explicitly parameterizes
geometric perturbations while preserving semantic content. Extensive experiments demonstrate that MarkCleaner achieves superior performance in both watermark removal effectiveness and visual fidelity, while enabling efficient real-time inference. Our code will be made available upon acceptance.
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All authors Xiaoxi Kong, Jieyu Yuan, Pengdi Chen, Yuanlin Zhang, Chongyi Li, Bin Li
Cryptography and Security
Implementation Challenges in Quantum Key Distribution
Abel C. H. Chen
In recent years,
quantum computing technologies have steadily matured and have begun to find practical applications across various domains. One important area is network communication security, where
Quantum Key Distribution (QKD) enables communicating parties to establish a shared secret that can then be used to generate symmetric keys for subsequent encryption and decryption. This study focuses on implementing and comparing two well-known QKD protocols, namely BB84 and E91, within an actual
quantum computing environment. It also proposes the use of SX gate operations to generate uniform
quantum superposition states. By leveraging the properties of
quantum superposition and
quantum entanglement, the study illustrates how communicating parties can securely obtain a shared secret while preventing adversaries from intercepting it. The experiments are conducted using the IBM
Quantum Platform to demonstrate the feasibility of the BB84 and E91 protocols on actual
quantum hardware. The evaluation considers several metrics, including
entropy, Independent and Identically Distributed (IID), and error-rate verifications.
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Cryptography and Security
Sleep Reveals the Nonce: Breaking ECDSA using Sleep-Based Power Side-Channel Vulnerability
Sahan Sanjaya and Prabhat Mishra
Security of
Elliptic Curve Digital Signature
Algorithm (ECDSA) depends on the secrecy of the per-signature nonce. Even partial nonce leakage can expose the long-term private key through
lattice-based cryptanalysis. In this paper, we introduce a previously unexplored power side-channel vulnerability that exploits sleep-induced power spikes to extract ECDSA nonces. Unlike conventional power-based side-channel attacks, this vulnerability leverages power fluctuations generated during processor context switches invoked by sleep functions. These fluctuations correlate with nonce-dependent operations in scalar multiplication, enabling nonce recovery even under constant-time and masked implementations. We evaluate the attack across multiple cryptographic libraries, RustCrypto, BearSSL, and GoCrypto, and processor architectures, including ARM and RISC-V. Our experiments show that subtle variations in the power envelope during sleep-induced context switches provide sufficient leakage for practical ECDSA nonce extraction, recovering 20 bits of the nonce. These results establish sleep-induced power spikes as a practical cross-platform side-channel threat and highlight the need to reconsider design choices in cryptographic systems.
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