Cryptography and Security
SoK: A Systematic Bidirectional Literature Review of AI & DLT Convergence
Ali Irzam Kathia, Yimika Erinle, Abylay Satybaldy et al. (+3 more)
The integration of Artificial Intelligence (AI) with Distributed Ledger Technology (DLT) has become a growing research area, yet contributions tend to cluster around specific application domains or examine only one direction of the integration, leaving the broader architectural interplay between the two technologies poorly understood. This work addresses that gap through a structured, bidirectional review of peer-reviewed studies published between 2020 and 2025. We classify contributions along two directions: AI-enhanced DLT, and DLT-enhanced AI. In the first case, we examine how AI techniques improve DLT systems across five layers: data, network, consensus, execution, and application layers. In the second case, we analyse how DLT supports AI systems across five layers: infrastructure, data, model, inference, and application layers, with particular
attention to
federated learning, model evaluation, and multi-
agent coordination. The analysis reveals that most works concentrate on a small subset of layers: execution and consensus for AI-enhanced DLT, data and model for DLT-enhanced AI. Other layers remain comparatively neglected. Despite reported improvements in controlled settings, no study demonstrates deployment at production scale, and the field has not yet offered satisfying answers to fundamental questions around scalability, interoperability, and verifiable execution. We argue that progress will require cross-layer co-design and empirical validation in real-world settings.
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All authors Ali Irzam Kathia, Yimika Erinle, Abylay Satybaldy, Paolo Tasca, Nikhil Vadgama, Marco Alberto Javarone
Cryptography and Security
A Note on Banaszczyk's Inequality
Hongyuan Qu, Chengliang Tian and Guangwu Xu
Banaszczyk's inequality establishes a tail estimate for the discrete Gaussian measure on a
lattice in $\mathbb{R}^n$. This classic result has been influential and plays an important role in
lattice-based cryptography. An improvement of the inequality with a transparent proof was given by Tian, Liu and Xu. In this note, we further improve this inequality by imposing an appropriate condition, obtaining a significantly better bound. This refined inequality can be used to investigate dual attacks against the Learning With Errors (LWE) problem.
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Cryptography and Security
DRIFT: Drift-Resilient Invariant-Feature Transformer for DGA Detection
Chaeyoung Lee, Chaeri Jung and Seonghoon Jeong
Domain Generation
Algorithms (DGAs) evolve continuously to evade botnet detection, posing a persistent challenge for dependable network defense. While deep learning-based detectors achieve strong performance under static conditions, they suffer severe degradation when facing temporal drift. Through a 9-year longitudinal study (2017-2025), we empirically show that state-of-the-art character- and word-based DGA classifiers rapidly lose effectiveness as new DGA variants emerge. To address this problem, we propose a drift-resilient
Transformer-based framework that learns invariant representations through a hybrid tokenization strategy and multi-task self-supervised pre-training. The model integrates (i) character-level encoding to capture
stochastic morphological patterns and (ii) subword-level encoding for word-based DGAs. Three pre-training tasks enable the model to learn robust structural and contextual features prior to supervised fine-tuning. Comprehensive evaluations demonstrate that our method significantly mitigates temporal degradation and consistently outperforms state-of-the-art baselines in forward-chaining experiments. The proposed approach offers a dependable foundation for long-term DGA defense in evolving threat landscapes. Our code is available at: https://github.com/snsec-net/2026-DSN-DRIFT.
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Cryptography and Security · Cross-listed from cs.AR
ObfAx: Obfuscation and IP Piracy Detection in Approximate Circuits
Lukas Sekanina and Vojtech Mrazek
Approximate
circuits often achieve exceptional trade-offs between computational accuracy and hardware efficiency, making them attractive for deployment as reusable Intellectual Property (IP) cores. However, safeguarding such
circuits against piracy is critical for enabling sustainable commercialization of approximate computing. This work addresses the emerging challenge of IP protection and piracy detection in the context of approximate hardware. We introduce a novel
adversarial threat model, approximate obfuscation, in which an attacker not only conceals the design through structural obfuscation but also introduces functional modifications to ensure that the resulting
circuit exhibits nearly identical error characteristics and hardware metrics as the original IP. To counter this threat, we propose an automated framework that extracts and compares statistical error profiles of protected IP cores and suspicious
circuits, enabling systematic detection of potential IP theft. Through extensive experiments on a diverse set of approximate multipliers, we analyze the resilience of different approximate multipliers against approximate obfuscation. Our results provide new insights into the interplay between obfuscation, approximation, and IP protection.
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Cryptography and Security
Mapping Partisan Fault Lines Within DAOs
Thomas Lloyd, Daire Ó Broin and Martin Harrigan
Decentralised Autonomous Organisations (DAO) can fragment when partisan communities emerge within their governance structures, leading to organisational splits known as "forks". We present a method to detect these emerging communities by analysing on-chain voting behaviour before fragmentation occurs. Our approach extracts voting events from governance smart contracts, constructs voter
matrices encoding participation patterns, and applies pairwise dissimilarity analysis to quantify voting divergence between addresses. We visualise these relationships using multidimensional scaling and identify partisan communities through k-means clustering with silhouette score optimisation. Using Nouns DAO as a case study, a protocol that has experienced multiple documented forks, we demonstrate that addresses that would later fork cluster together months before actual fragmentation events. Our analysis of 330 proposals spanning from contract deployment to the first major fork shows that 90% of fork addresses cluster together in the final 44 proposals, compared with only 47% in randomised data. These results indicate that partisan communities can be detected and visualised through on-chain governance analysis, providing retrospective evidence of emerging divisions before they cause organisational fragmentation.
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Cryptography and Security · Cross-listed from cs.LG
DP-LAC: Lightweight Adaptive Clipping for Differentially Private Federated Fine-tuning of Language Models
Haaris Mehmood, Jie Xu, Karthikeyan Saravanan et al. (+2 more)
Federated learning (FL) enables the collaborative training of large-scale
language models (LLMs) across edge devices while keeping user data on-device. However, FL still exposes sensitive information through client-provided gradients. Differentially private
stochastic gradient descent (DP-SGD) mitigates this risk by clipping each client's contribution to a threshold $C$ and adding noise proportional to $C$. Existing adaptive clipping techniques dynamically adjust $C$ but demand tedious hyperparameter tuning, which can erode the
privacy budget. In this paper, we introduce DP-LAC, a method that first estimates an initial clipping threshold within an order of magnitude of the optimum using private histogram estimation, and then adapts this threshold during training without consuming additional
privacy budget or introducing new hyperparameters. Empirical results show that DP-LAC outperforms both state-of-the-art adaptive clipping methods and vanilla DP-SGD, achieving an average accuracy gain of $6.6\%$.
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All authors Haaris Mehmood, Jie Xu, Karthikeyan Saravanan, Rogier Van Dalen, Mete Ozay
Cryptography and Security
Knowledge Poisoning Attacks on Medical Multi-Modal Retrieval-Augmented Generation
Peiru Yang, Haoran Zheng, Tong Ju et al. (+6 more)
Retrieval-augmented generation (RAG) is a widely adopted paradigm for enhancing LLMs in medical applications by incorporating expert
multimodal knowledge during generation. However, the underlying
retrieval databases may naturally contain, or be intentionally injected with,
adversarial knowledge, which can perturb model outputs and undermine system reliability. To investigate this risk, prior studies have explored knowledge poisoning attacks in medical RAG systems. Nevertheless, most of them rely on the strong assumption that adversaries possess prior knowledge of user queries, which is unrealistic in deployments and substantially limits their practical applicability. In this paper, we propose M\textsuperscript{3}Att, a knowledge-poisoning framework designed for medical
multimodal RAG systems, assuming only limited distribution knowledge of the underlying database. Our core idea is to inject covert misinformation into textual data while using paired visual data as a query-agnostic trigger to promote
retrieval. We first propose a unified framework that introduces imperceptible perturbations to visual inputs to manipulate
retrieval probabilities. Besides, due to the prior medical knowledge in LLMs, naively poisoned medical content with explicit factual errors can be corrected during generation. Thus, we leverage the inherent ambiguity of medical diagnosis and design a covert misinformation injection strategy that degrades diagnostic accuracy while evading model self-correction. Experiments on five LLMs and
datasets demonstrate that M\textsuperscript{3}Att consistently produces clinically plausible yet incorrect generations. Codes: https://github.com/ypr17/M3Att.
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All authors Peiru Yang, Haoran Zheng, Tong Ju, Shiting Wang, Wanchun Ni, Jiajun Liu, Shangguang Wang, Yongfeng Huang, Tao Qi
Cryptography and Security · Cross-listed from cs.SE
MARGIN: Margin-Aware Regularized Geometry for Imbalanced Vulnerability Detection
Yuteng Zhang, Huifang Ma, Jiahui Wei et al. (+2 more)
Software vulnerability detection is critical for ensuring software security and reliability. Despite recent advances in deep learning, real-world vulnerability
datasets suffer from two severe challenges: frequency imbalance and difficulty imbalance. We reinterpret these challenges from an
embedding geometry perspective, observing that such imbalances induce
geometric distortions in hyperspherical representation space. To address this issue, we propose MARGIN, a metric-based framework that learns discriminative vulnerability representations through adaptive margin metric learning and hyperspherical prototype modeling. MARGIN dynamically adjusts
geometric regularization according to the distribution structure estimated by the von Mises-Fisher concentration, aligning the probability mass of
embedding distributions with their corresponding Voronoi
cells, thereby reducing
geometric distortion and yielding more stable decision boundaries. Extensive experiments on public vulnerability
datasets show that MARGIN consistently outperforms strong baselines, achieving notable improvements in classification and detection, especially on challenging, imbalanced
datasets. Further analysis demonstrates that MARGIN produces more structured
embedding geometries, improving robustness, interpretability, and generalization.
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All authors Yuteng Zhang, Huifang Ma, Jiahui Wei, Qingqing Li, Yafei Yang
Cryptography and Security · Cross-listed from cs.CV
What Concepts Lie Within? Detecting and Suppressing Risky Content in Diffusion Transformers
Chenyu Zhang
The rise of text-to-image (T2I) models has increasingly raised concerns regarding the generation of risky content, such as sexual, violent, and copyright-protected images, highlighting the need for effective safeguards within the models themselves. Although existing methods have been proposed to eliminate risky concepts from T2I models, they are primarily developed for earlier U-Net architectures, leaving the state-of-the-art
Diffusion-
Transformer-based T2I models inadequately protected. This gap stems from a fundamental architectural shift:
Diffusion Transformers (DiTs) entangle semantic injection and visual synthesis via joint
attention, which makes it difficult to isolate and erase risky content within the generation. To bridge this gap, we investigate how semantic concepts are represented in DiTs and discover that
attention heads exhibit concept-specific sensitivity. This property enables both the detection and suppression of risky content. Building on this discovery, we propose AHV-D&S, a training-free inference-time safeguard for image generation in DiTs. Specifically, AHV-D&S quantifies each textual
token's sensitivity across all
attention heads as an
Attention Head Vector (AHV), which serves as a discriminative signature for detecting risky generation tendencies. In the inference stage, we propose a momentum-based strategy to dynamically track
token-wise AHVs across denoising steps, and a sensitivity-guided adaptive suppression strategy that suppresses the
attention weights of identified risky
tokens based on head-specific risk scores. Extensive experiments demonstrate that AHV-D&S effectively suppresses sexual, copyrighted-style, and various harmful content while preserving visual quality, and further exhibits strong robustness against
adversarial prompts and transferability across different DiT-based T2I models.
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Cryptography and Security
When Prompts Become Payloads: A Framework for Mitigating SQL Injection Attacks in Large Language Model-Driven Applications
Farzad Nourmohammadzadeh Motlagh, Mehrdad Hajizadeh, Mehryar Majd et al. (+3 more)
Natural
language interfaces to structured databases are becoming increasingly common, largely due to advances in large
language models (LLMs) that enable users to query data using conversational input rather than formal query
languages such as SQL. While this paradigm significantly improves usability and accessibility, it introduces new security risks, particularly the amplification of SQL injection vulnerabilities through the
prompt-to-SQL translation process. Malicious users can exploit these mechanisms by crafting
adversarial prompts that manipulate model behavior and generate unsafe queries. In this work, we propose a multi-layered security framework designed to detect and mitigate LLM-mediated SQL injection attacks. The framework integrates a front-end security shield for
prompt sanitization, an advanced threat detection model for behavioral and semantic anomaly identification, and a signature-based control layer for known attack patterns. We evaluate the proposed framework under diverse and realistic attack scenarios, including
prompt injection, obfuscated SQL payloads, and context-manipulation attacks. To ensure robustness, we generate and curate a comprehensive
benchmark dataset of
adversarial prompts and assess performance across a fine-tuned LLM configuration. Experimental results demonstrate that the proposed approach achieves high detection accuracy while maintaining low false-positive rates, significantly improving the secure deployment of LLM-powered database applications.
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All authors Farzad Nourmohammadzadeh Motlagh, Mehrdad Hajizadeh, Mehryar Majd, Pejman Najafi, Feng Cheng, Christoph Meinel
Cryptography and Security
Key Encapsulation Mechanism-Based Integrated Encryption Scheme (KEM-IES)
Abel C. H. Chen
The
Elliptic Curve Integrated Encryption Scheme (ECIES) is widely regarded as a practical method and has been adopted by multiple standards. However, the advancement of
quantum computing technologies poses potential security risks to ECIES. Therefore, this study proposes a Key Encapsulation Mechanism-Based Integrated Encryption Scheme (KEM-IES), which enhances resistance to
quantum attacks by incorporating a Post-
Quantum Cryptography (PQC)-based Key Encapsulation Mechanism (KEM). Furthermore, the study integrates the Ascon
algorithm, released by the National Institute of Standards and Technology (NIST) in August 2025, to further improve computational efficiency and enable applicability to embedded systems. The proposed KEM-IES and its Ascon-based variant are implemented on a Raspberry Pi 4, and evaluations are conducted to compare the performance of ECIES and KEM-IES.
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Cryptography and Security · Cross-listed from cs.AI
Benchmarking Safety Risks of Knowledge-Intensive Reasoning under Malicious Knowledge Editing
Qinghua Mao, Xi Lin, Jinze Gu et al. (+3 more)
Large
language models (LLMs) increasingly rely on knowledge editing to support knowledge-intensive
reasoning, but this flexibility also introduces critical safety risks: adversaries can inject malicious or misleading knowledge that corrupts downstream
reasoning and leads to harmful outcomes. Existing knowledge editing
benchmarks primarily focus on editing efficacy and lack a unified framework for systematically evaluating the safety implications of edited knowledge on
reasoning behavior. To address this gap, we present EditRisk-Bench, a
benchmark for systematically evaluating safety risks of knowledge-intensive
reasoning under malicious knowledge editing. Unlike prior
benchmarks that mainly emphasize edit success, generalization, and locality, EditRisk-Bench focuses on how injected knowledge affects downstream
reasoning behavior and reliability. It integrates diverse malicious scenarios, including misinformation, bias, and safety violations, together with multi-level knowledge-intensive
reasoning tasks and representative editing strategies within a unified evaluation framework measuring attack effectiveness,
reasoning correctness, and side effects. Extensive experiments on both open-source and closed-source LLMs show that malicious knowledge editing can reliably induce incorrect or unsafe
reasoning while largely preserving general capabilities, making such risks difficult to detect. We further identify several key factors influencing these risks, including edit scale, knowledge characteristics, and
reasoning complexity. EditRisk-Bench provides an extensible testbed for understanding and mitigating safety risks in knowledge editing for LLMs.
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All authors Qinghua Mao, Xi Lin, Jinze Gu, Jun Wu, Siyuan Li, Yuliang Chen
Cryptography and Security
Usability as a Weapon: Attacking the Safety of LLM-Based Code Generation via Usability Requirements
Yue Li, Xiao Li, Hao Wu et al. (+5 more)
Large
Language Models (LLMs) are increasingly used for automated software development, making their ability to preserve secure coding practices critical. In practice, however, many security requirements are implicit or underspecified, whereas usability requirements are explicit and high-signal. This asymmetry motivates our investigation of usability pressure as a practical attack surface: realistic usability-oriented requirements (e.g., new features, performance constraints, or simplicity demands) can cause coding LLMs to satisfy explicit usability goals while silently dropping implicit security constraints – a form of reward hacking. We formalize this threat as UPAttack and propose U-SPLOIT, an automated framework to craft UPAttack that (i) selects tasks where a model is initially secure, (ii) synthesizes usability pressures by identifying usability rewards of insecure alternatives across three vectors (Functionality, Implementation, Trade-off), and (iii) verifies security regression via both existing test cases and dynamically generated exploit payloads. Across 75 seed scenarios (25 CWEs x 3 cases), spanning multiple
languages (Python, C, and JavaScript), U-SPLOIT achieves attack success rates up to 98.1% on multiple state-of-the-art models (e.g., GPT-5.2-chat and Gemini-3-Flash-Preview).
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All authors Yue Li, Xiao Li, Hao Wu, Yue Zhang, Yechao Zhang, Yating Liu, Fengyuan Xu, Sheng Zhong
Cryptography and Security
Agentic Fuzzing: Opportunities and Challenges
Junyoung Park and Insu Yun
Fuzzers and static analyzers find many bugs but struggle with logic bugs in mature codebases. Triggering such a bug often requires multi-step
reasoning that produces no distinctive execution feedback, and variants can appear across implementations too different for a single pattern to match. Recent LLM-assisted approaches help, but they use LLMs as auxiliaries rather than as the
reasoning engine. We propose agentic fuzzing, a bug-finding approach seeded by historical bugs in which deep
agents perform the
reasoning directly. Given a reference bug, the
agent analyzes its root cause, hypothesizes new scenarios elsewhere in the codebase that may share that cause, and verifies each hypothesis by generating and running proof-of-concept code. This lets the
agent find variants that differ completely in trigger path or code structure from the reference. We identify three practical challenges in implementing agentic fuzzing: harness engineering, redundant investigations across seeds with similar root causes, and scheduling seeds in a large corpus. We address these in AFuzz through a four-stage
agent pipeline, scenario coverage that deduplicates previously explored scenarios, and a DPP-MAP scheduler that orders seeds by diversity. We ran AFuzz on the V8 JavaScript engine for about one month, finding 40 bugs (including three duplicates), receiving a total $35,000 bounty, and being assigned two CVEs. AFuzz also found 19 bugs (including one duplicate) in SpiderMonkey and JavaScriptCore using the seeds from V8. However, agentic fuzzing is in its early stages with several remaining open problems we discuss in the paper. Still, we think it points to a promising direction for finding logic bugs.
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Cryptography and Security
Hardness Amplification for (Sparse) LPN
Divesh Aggarwal, Rishav Gupta and Li Zeyong
We prove new hardness amplification results for Learning Parity with Noise ($\mathsf{LPN}$) and its sparse variants. In $\mathsf{LPN}_{\eta,n,m}$, the goal is to recover a secret $\vec s\in\mathbb{F}_2^n$ from $m$ noisy linear samples $(\vec a,b)$, where $\vec a\leftarrow \mathbb{F}_2^n$ is uniform and $b=\langle \vec a,\vec s\rangle + e$ with $e\leftarrow \mathrm{Ber}(\eta)$. Building on the direct-product framework introduced by Hirahara and Shimizu [HS23], we show an 'instance-fraction amplification'
theorem: for any $\varepsilon,\delta>0$, any
algorithm that solves $\mathsf{LPN}_{\eta,n,m}$ with success probability $\varepsilon$ can be transformed into an
algorithm that succeeds with probability $1-\delta$ on a related $\mathsf{LPN}$ distribution with scaled parameters $\mathsf{LPN}_{\eta/k,\;n/k,\;m}$, where $ k=\Theta\!\left(\frac{1}{\delta}\log\frac{1}{\varepsilon}\right). $ Equivalently, an
algorithm that solves $\mathsf{LPN}$ on a 'small fraction of instances' can be converted into an
algorithm that solves $\mathsf{LPN}$ on 'almost all instances', yielding a self-amplification for a wide range of parameters. We extend the same amplification approach to $\mathsf{LPN}$ over $\mathbb{F}_q$ and to Sparse-$\mathsf{LPN}$, where each query vector $\vec a$ has exactly $\sigma$ nonzero entries. Together, these results establish hardness self-amplification for a broad family of $\mathsf{LPN}$-type problems, strengthening the foundations for assuming the average-case hardness of $\mathsf{LPN}$ and its sparse variants.
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Cryptography and Security
Janus: Compiler-Based Defense Against Transient Execution Attacks Using ARM Hardware Primitives
Ciyan Ouyang, Peinan Li, Yubiao Huang et al. (+2 more)
We present Janus, a compiler-based security framework that mitigates transient execution attacks like Spectre and control-flow hijacking on ARM64 platforms. Janus integrates speculative execution and control flow dependencies with PA modifiers, using PA and BTI microarchitectural features to prevent control-flow speculation attacks and secure both control flow and speculative execution through existing control-flow integrity mechanisms. To optimize performance, Janus minimizes overhead by merging defense operations across different defense layers (modifier fusion) and reusing registers of protected variables (carrier reuse), while maintaining strong security guarantees. Evaluation on SPEC CPU2017 shows an average performance overhead of 3.85%, with real-world applications exhibiting overheads ranging from 2.97% to 7.80%. Janus offers effective speculative execution security and low performance and code size overhead, making it a robust solution for ARM-based systems.
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All authors Ciyan Ouyang, Peinan Li, Yubiao Huang, Dan Meng, Rui Hou
Cryptography and Security · Cross-listed from stat.ML
Differentially Private Sampling from Distributions via Wasserstein Projection
Shokichi Takakura, Seng Pei Liew and Satoshi Hasegawa
In this paper, we study the problem of sampling from a distribution under the constraint of differential
privacy (DP). Prior works measure the utility of DP sampling with density ratio-based measures such as KL divergence. However, such formulations suffer from two key limitations: 1) they fail to capture the
geometric structure of the support, and 2) they are not applicable when the supports of the distributions differ. To deal with these issues, we develop a novel framework for DP sampling with Wasserstein distance as the utility measure. In this formulation, we propose Wasserstein Projection Mechanism (WPM), a minimax optimal mechanism based on Wasserstein projection. Furthermore, we develop efficient
algorithms for computing the proposed mechanisms approximately and provide convergence guarantees.
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Cryptography and Security · Cross-listed from cs.HC
When Are LLM Inferences Acceptable? User Reactions and Control Preferences for Inferred Personal Information
Kyzyl Monteiro, Minjung Park, Alexander Ioffrida et al. (+5 more)
Ask ChatGPT about vacation planning, and it may infer your income. Ask it about medication, and it may infer your medical history. Because such inferences can expose more information than users intend to reveal, prior work argues that they are a defining
privacy risk of LLM-based systems. Yet prior work has mostly shown that LLMs can make potentially violating inferences, not how users experience those inferences nor what controls users may want governing their use. We built the Reflective Layer, a visualization tool that surfaces example unstated inferences from users' own ChatGPT histories, and used it in a mixed-methods study with 18 regular ChatGPT users evaluating 215 surfaced inferences from their own conversations. Counterintuitively, participants reacted more strongly with curiosity and interest rather than distress and concern. Discomfort arose mainly when inferences felt misrepresentative of the user or misaligned with expected use. Participants were also markedly less comfortable with advertisers and third-party applications using those inferences than with platform providers. These findings suggest that the acceptability of LLM inferences is governed not only by its content, but by context-sensitive norms around how they are generated, retained within the platform, and transmitted beyond it.
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All authors Kyzyl Monteiro, Minjung Park, Alexander Ioffrida, Angelina Sanna, Hao-Ping Lee, Niloofar Mireshghallah, Yang Wang, Sauvik Das
Cryptography and Security · Cross-listed from cs.HC
Sketch-based Access Control: A Multimodal Interface for Translating User Preferences into Intent-Aligned Policies
Kyzyl Monteiro and Sauvik Das
Developing simple and expressive access controls – interfaces to specify policies that define who should have access to resources and under what circumstances – is a longstanding challenge in usable security. We present Sketch-based Access Control (SBAC), a sketch-based, AI-assisted access control authoring system that combines the expressive power of sketching with the interpretive capabilities of
multimodal large
language models (MLLMs) to support the interpretation and validation of policy specifications as they are iteratively refined. Through a formative study with 14 participants, we identified three design requirements and developed a human-AI collaborative workflow composed of three stages – Specify, Analyze, and Test – enabled by the system's ability to maintain and interpret evolving access control specifications. In a user evaluation with 14 participants grounded in their real-world access control scenarios, we found the system and the workflow helped participants progressively refine initially underspecified preferences into more complete and precise policies – surfacing gaps they had not anticipated, resolving ambiguities through dialogue, and validating policy behavior through concrete scenarios.
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Cryptography and Security
Towards LLM-Based Analysis of Virtualization-Obfuscated Code through Automated Data Generation
Sangjun An, Hyeyeon Park, Yejin Son et al. (+2 more)
Virtualization-based obfuscation produces extremely large and structurally complex binaries, posing challenges for LLM-based analysis due to input size limits and the need for large-scale labeled data. We address this by focusing on structural rather than full semantic analysis. Obfuscated binaries are decomposed into the largest semantically coherent units that fit within LLM constraints and are labeled according to their structural roles. We implement a static analysis framework to automate labeling and enable large-scale
dataset generation. Our prototype shows strong performance on real-world virtualization obfuscators.
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All authors Sangjun An, Hyeyeon Park, Yejin Son, Seoksu Lee, Eun-Sun Cho
Cryptography and Security · Cross-listed from quant-ph
On Scalable Pseudorandom Unitaries and the Unitary Synthesis Problem
Zvika Brakerski and Henry Yuen
We consider the task of constructing pseudorandom
unitaries (PRUs) with scalable security, i.e. families in which the security parameter may vary independently of the dimension (or input bit-length). It is not known whether scalable PRUs can be constructed. In this work we show that if scalable PRUs can be constructed via the prevailing paradigm for analyzing PRUs, then there would be a positive solution to the Aaronson-Kuperberg
unitary synthesis problem, a longstanding question in
quantum complexity theory about whether implementing arbitrary
unitaries can be efficiently reduced to computing a Boolean function. Specifically, we formalize the notion of ROM-PRUs, which are statistically secure PRUs in the random oracle model (ROM). All prior known constructions of cryptographically secure PRUs are based on a ROM-PRU construction. We prove novel connections between ROM-PRUs, approximate
unitary designs, epsilon-nets over the
unitary group, and the
unitary synthesis problem. In particular, we prove that any
unitary synthesis
algorithm (and thus any ROM-PRU) must use a classical oracle with input length (2 - o(1)) log d bits, where d is the dimension of the
unitary to be implemented. This bound rules out all existing candidates for scalable PRUs in the literature. Together, these connections indicate that ROM-PRUs provide a fruitful idealized model for studying pseudorandom
unitaries.
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Cryptography and Security · Cross-listed from cs.CV
Evidence-based Decision Modeling for Synthetic Face Detection with Uncertainty-driven Active Learning
Qingchao Jiang, Zhenxuan Hou, Zhiying Zhu et al. (+3 more)
With the rapid development of deep generative models, forged facial images are massively exploited for illegal activities. Although existing synthetic face detection methods have achieved significant progress, they suffer from the inherent limitation of overconfidence due to their reliance on the Softmax activation function. Thus, these methods often lead to unreliable predictions when encountering unknown Out-of-Distribution (OOD) images, and cannot ascertain the model's uncertainty in its prediction. Meanwhile, most existing methods require massive high-quality annotated data, which greatly limits their practicability across diverse scenarios. To address these limitations, we propose EMSFD (Evidence-based decision Modeling for Synthetic Face Detection with uncertainty-driven active learning), an approach designed to enhance detection reliability and generalizability. Specifically, EMSFD models class evidence using the Dirichlet distribution and explicitly incorporates model uncertainty into the prediction process. Furthermore, during training, the estimated uncertainty is exploited to prioritize more informative samples from the unlabeled pool for annotation, thereby reducing labeling cost and improving model generalization. Extensive experimental evaluations demonstrate that our method enhances the interpretability of synthetic face detection. Meanwhile, our method yields a 15% increase in accuracy compared to existing state-of-the-art (SOTA) baselines, which demonstrates the superior detection performance and generalizability of our approach. Our code is available at: https://github.com/hzx111621/EMSFD.
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All authors Qingchao Jiang, Zhenxuan Hou, Zhiying Zhu, Zhenxing Qian, Xinpeng Zhang, Zaiwang Gu
Cryptography and Security
Deep Learning under Fractional-Order Differential Privacy
Mohammad Partohaghighi and Roummel Marcia
Differentially private
stochastic gradient descent (DP-SGD) is a standard approach to
privacy-preserving learning based on per-example clipping, subsampling, Gaussian perturbation, and
privacy accounting. Classical DP-SGD releases a noisy version of the current clipped subsampled gradient sum. We propose Fractional-Order Differentially Private
Stochastic Gradient Descent (FO-DP-SGD), a mechanism-level extension that replaces this current-only query, before Gaussian noise is added, with a fractional recursive query combining the current clipped sum with a finite-window, power-law-weighted aggregation of previously released private sum-level outputs. This injects fractional
memory into the release mechanism while preserving the standard sum-then-noise-then-divide structure. Under add/remove adjacency with Poisson subsampling, the current-step sensitivity analysis shows that the only newly data-dependent term is the scaled current clipped sum. Hence, conditioned on the private history, the effective \(\ell_2\)-sensitivity is at most \(\beta C\), where \(C\) is the clipping threshold and \(\beta\in(0,1]\) controls the current-step contribution. Thus, FO-DP-SGD admits standard per-step Rényi differential
privacy accounting via a Poisson-subsampled Gaussian mechanism with effective noise-to-sensitivity ratio \(\sigma/\beta\), and composes to yield overall \((\varepsilon,\delta)\)-differential
privacy guarantees. FO-DP-SGD provides a framework for studying long-
memory effects in private optimization. The fractional order,
memory window, and mixing coefficient govern the trade-off among current-step sensitivity, signal retention, and private-history influence. Experiments on SVHN, CIFAR-10, and CIFAR-100 show improved test accuracy and
privacy–utility performance over DP-SGD and private baselines including DP-Adam, DP-IS, SA-DP-SGD, ADP-AdamW, DP-SAT, and DP-Adam-AC.
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Cryptography and Security
Nautilus Compass: Black-box Persona Drift Detection for Production LLM Agents
Chunxiao Wang
Production LLM coding
agents drift over long sessions: they forget user-specified constraints, slip into mistakes the user already flagged, and confabulate prior agreements. White-box approaches such as persona vectors require model weights and so cannot be applied to closed APIs (Claude, GPT-4) that most users actually interact with. We present Nautilus Compass, a black-box persona drift detector and
agent memory layer for production coding
agents. The method operates entirely at the
prompt-text layer: cosine similarity between user
prompts and behavioral anchor texts, aggregated by a weighted top-k mean using BGE-m3
embeddings. Compass is, to our knowledge, the only public
agent memory layer (among Mem0, Letta, Cognee, Zep, MemOS, smrti verified May 2026) that does not call an LLM at index time to extract facts or build a graph; raw conversation text is embedded directly. The system ships as a Claude Code plugin, an MCP 2024-11-05 A2A server (Cursor, Cline, Hermes), a CLI, and a REST API on one daemon, with a Merkle-chained audit log for tamper-evident anchor updates. On a held-out test set built from real Claude Code session traces and labeled by an independent LLM judge, Compass reaches ROC AUC 0.83 for drift detection. The embedded
retrieval pipeline scores 56.6% on LongMemEval-S v0.8 and 44.4% on EverMemBench-Dynamic (n=500), topping the four published EverMemBench Table 4 baselines. LongMemEval-S 56.6% is ~30 points below recent white-box leaders (90+%); we treat that as the architectural ceiling of the no-extraction design. End-to-end reproduction cost is $3.50 (~14x cheaper than GPT-4o-judged stacks). A paired cross-vendor behavior A/B accompanies these numbers as preliminary system-level evidence. Code, anchors, frozen test data, and audit-log tooling are MIT-licensed at github.com/chunxiaoxx/nautilus-compass.
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