Cryptography and Security · Cross-listed from cs.AI
AgentWall: A Runtime Safety Layer for Local AI Agents
Ashwin Aravind
The safety of autonomous AI
agents is increasingly recognized as a critical open problem. As
agents transition from passive text generators to active actors capable of executing shell commands, modifying files, calling APIs, and browsing the web, the consequences of unsafe or adversarially manipulated behavior become immediate and tangible. Existing AI safety work has focused primarily on model
alignment and input filtering, but these approaches do not address what happens at the moment an
agent's intent becomes a real action on a real machine. This gap is especially acute in local environments, where developers run
agents against their own filesystems, credentials, and infrastructure with little runtime control. This paper introduces AgentWall, a runtime safety and observability layer for local AI
agents. AgentWall intercepts every proposed
agent action before it reaches the host environment, evaluates it against an explicit declarative policy, requires human approval for sensitive operations, and records a complete execution trail for audit and replay. It is implemented as a policy-enforcing MCP proxy and native OpenClaw plugin, working across Claude Desktop, Cursor, Windsurf, Claude Code, and OpenClaw with a single install command. We present the design, architecture, threat model, and policy model of AgentWall, and demonstrate 92.9% policy enforcement accuracy with sub-millisecond overhead across 14
benchmark tests. AgentWall is open-source at https://github.com/agentwall/Agentwall.
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Cryptography and Security · Cross-listed from cs.CL
Foundational Study on Authorship Attribution of Japanese Web Reviews for Actor Analysis
Hiroshi Matsubara, Shingo Matsugaya, Taichi Aoki et al. (+1 more)
This study investigates the applicability of authorship attribution based on stylistic features to support actor analysis in threat intelligence. As a foundational step toward future application to dark web forums, we conducted experiments using Japanese review data from clear web sources. We constructed
datasets from Rakuten Ichiba reviews and compared four methods: TF-IDF with logistic regression (TF-IDF+LR), BERT
embeddings with logistic regression (BERT-Emb+LR), BERT fine-tuning (BERT-FT), and metric learning with $k$-nearest neighbors (Metric+kNN). Results showed that BERT-FT achieved the best performance; however, training became unstable as the number of authors scaled to several hundred, where TF-IDF+LR proved superior in terms of accuracy, stability, and computational cost. Furthermore, Top-$k$ evaluation demonstrated the utility of candidate screening, and error analysis revealed that boilerplate text, topic dependency, and short text length were primary factors causing misclassification.
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All authors Hiroshi Matsubara, Shingo Matsugaya, Taichi Aoki, Masaki Hashimoto
Cryptography and Security · Cross-listed from astro-ph.SR
Out-of-Domain Stress Test for Temporal Braid Group Privilege Escalation Detection
Christophe Parisel
In a companion paper, we prove that the Burau-Lyapunov exponent LE discriminates focused from dispersed privilege escalation ratchets in cloud IAM graphs, and that no abelian statistic can replicate this discrimination. To strengthen this claim beyond its synthetic validation corpus, we apply the identical pipeline, with zero parameter retuning, to
solar coronal
magnetic fields: a physical system with no connection to cloud identity and access management, whose binary eruptive/confined outcome is independently established by decades of astrophysical observation.
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Cryptography and Security
AetherWeave: Sybil-Resistant Robust Peer Discovery with Stake
Kaya Alpturer, Constantine Doumanidis and Aviv Zohar
Peer-discovery protocols within P2P networks are often vulnerable: because creating network identities is essentially free, adversaries can eclipse honest nodes or partition the overlay. This threat is especially acute for blockchains, whose security depends on resilient peer connectivity. We present AetherWeave, a stake-backed peer-discovery protocol that ties network participation to deposited stake, raising the cost of large-scale attacks. We prove that, with high probability, either the honest overlay remains connected or a $(1{-}\delta)$-fraction of nodes in every smaller component raise an attack-detection flag – even against a very powerful adversary. To our knowledge, AetherWeave is the first peer-discovery protocol to simultaneously provide Sybil resistance and
privacy: nodes prove they hold valid stake without revealing which deposit they own, and gossiping does not expose peer-table contents. A cryptographic commitment scheme rate-limits discovery requests per round; exceeding the limit yields a publicly verifiable misbehavior proof that triggers on-chain slashing. Beyond deposit and slashing, the protocol requires no on-chain interaction, with per-node communication scaling as $O(s\sqrt{n})$. We validate our design through a mean-field analysis with closed-form convergence bounds, extensive
adversarial simulations, and an end-to-end prototype built by forking Prysm, a leading Ethereum consensus client.
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Cryptography and Security
The Cognitive Firewall:Securing Browser Based AI Agents Against Indirect Prompt Injection Via Hybrid Edge Cloud Defense
Qianlong Lan and Anuj Kaul
Deploying large
language models (LLMs) as autonomous browser
agents exposes a significant attack surface in the form of Indirect
Prompt Injection (IPI). Cloud-based defenses can provide strong semantic analysis, but they introduce latency and raise
privacy concerns. We present the Cognitive Firewall, a three-stage split-compute architecture that distributes security checks across the client and the cloud. The system consists of a local visual Sentinel, a cloud-based Deep Planner, and a deterministic Guard that enforces execution-time policies. Across 1,000
adversarial samples, edge-only defenses fail to detect 86.9% of semantic attacks. In contrast, the full hybrid architecture reduces the overall attack success rate (ASR) to below 1% (0.88% under static evaluation and 0.67% under adaptive evaluation), while maintaining deterministic constraints on side-effecting actions. By filtering presentation-layer attacks locally, the system avoids unnecessary cloud inference and achieves an approximately 17,000x latency advantage over cloud-only baselines. These results indicate that deterministic enforcement at the execution boundary can complement probabilistic
language models, and that split-compute provides a practical foundation for securing interactive LLM
agents.
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Cryptography and Security
Leveraging Large Language Models for Trustworthiness Assessment of Web Applications
Oleksandr Yarotskyi, José D'Abruzzo Pereira and João R. Campos
The widespread adoption of web applications has made their security a critical concern and has increased the need for systematic ways to assess whether they can be considered trustworthy. However, "trust" assessment remains an open problem as existing techniques primarily focus on detecting known vulnerabilities or depend on manual evaluation, which limits their scalability; therefore, evaluating adherence to secure coding practices offers a complementary, pragmatic perspective by focusing on observable development behaviors. In practice, the identification and verification of secure coding practices are predominantly performed manually, relying on expert knowledge and code reviews, which is time-consuming, subjective, and difficult to scale. This study presents an empirical methodology to automate the trustworthiness assessment of web applications by leveraging Large
Language Models (LLMs) to verify adherence to secure coding practices. We conduct a comparative analysis of
prompt engineering techniques across five state-of-the-art LLMs, ranging from baseline zero-shot classification to
prompts enriched with semantic definitions, structural context derived from call graphs, and explicit instructional guidance. Furthermore, we propose an extension of a hierarchical Quality Model (QM) based on the Logic Score of Preference (LSP), in which LLM outputs are used to populate the model's quality attributes and compute a holistic trustworthiness score. Experimental results indicate that excessive structural context can introduce noise, whereas rule-based instructional prompting improves assessment reliability. The resulting trustworthiness score allows discriminating between secure and vulnerable implementations, supporting the feasibility of using LLMs for scalable and context-aware trust assessment.
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Cryptography and Security
Space Fabric: A Satellite-Enhanced Trusted Execution Architecture
Filip Rezabek, Dahlia Malkhi and Amir Yahalom
The emergence of decentralized satellite networks creates a pressing need for trust architectures that operate without physical access to hardware, without pre-provisioned vendor secrets, and without dependence on a single manufacturer's attestation service. Terrestrial TEEs are insufficient: hardware-based designs are susceptible to physical attacks, and most platforms root their attestation chains in secrets provisioned during manufacturing, creating a pre-launch trust window and single-vendor dependency that cannot be independently audited. We present Space Fabric, an architecture that provides the missing trust foundation for orbital computing by relocating the trusted computing stack to satellite infrastructure, exploiting post-launch physical inaccessibility as a tamper barrier unattainable by terrestrial deployments. Our Satellite Execution Assurance Protocol binds workload execution to a specific satellite via a Byzantine-tolerant endorsement quorum of distributed ground stations, certifying not only what executes inside the TEE but also where. All cryptographic secrets are generated within co-located secure elements after launch, with no signing keys accessible on Earth at any point. To reduce single-vendor dependence, Space Fabric distributes its trust anchor across two independent secure elements, an NXP SE050 and a TROPIC01, both of which must co-sign attestation evidence. We implement Space Fabric on a USB Armory Mk II with ARM TrustZone, verify attestation end-to-end using Veraison, and provide a security analysis with satisfaction arguments and impossibility bounds under a strong adaptive adversary.
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Cryptography and Security
n-VM: A Multi-VM Layer-1 Architecture with Shared Identity and Token State
Jian Sheng Wang
Multi-chain ecosystems suffer from fragmented identity, siloed liquidity, and bridge-dependent
token transfers. We present n-VM, a Layer-1 architecture that hosts n heterogeneous virtual machines as co-equal execution environments over shared consensus and shared state. The design combines three components: a dispatcher that routes transactions by opcode prefix, a unified identity layer in which one 32-byte commitment anchors VM-specifific addresses, and a unified
token ledger that exposes VM-native interfaces such as ERC-20 and SPL over a common balance store. We formalize routing, identity derivation, and
token transfer semantics, and prove cross-VM transfer atomicity and identity isolation under standard cryptographic assumptions. We describe a concrete instantiation with five VMs: a native runtime, EVM, SVM, Bitcoin Script, and TVM. We also present context-based sharding and a write-set scheduler for parallel execution. Under an analytical throughput model, the architecture admits a projected range of about 16,000 to 66,000 transactions per second on commodity hardware.
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Cryptography and Security · Cross-listed from cs.LG
Byzantine-Robust and Differentially Private Federated Optimization under Weaker Assumptions
Rustem Islamov, Grigory Malinovsky, Alexander Gaponov et al. (+3 more)
Federated Learning (FL) enables heterogeneous clients to collaboratively train a shared model without centralizing their raw data, offering an inherent level of
privacy. However, gradients and model updates can still leak sensitive information, while malicious servers may mount
adversarial attacks such as Byzantine manipulation. These vulnerabilities highlight the need to address differential
privacy (DP) and Byzantine robustness within a unified framework. Existing approaches, however, often rely on unrealistic assumptions such as bounded gradients, require auxiliary server-side
datasets, or fail to provide convergence guarantees. We address these limitations by proposing Byz-Clip21-SGD2M, a new
algorithm that integrates robust aggregation with double momentum and carefully designed clipping. We prove high-probability convergence guarantees under standard $L$-smoothness and $\sigma$-sub-Gaussian gradient noise assumptions, thereby relaxing conditions that dominate prior work. Our analysis recovers state-of-the-art convergence rates in the absence of adversaries and improves utility guarantees under Byzantine and DP settings. Empirical evaluations on CNN and MLP models trained on MNIST further validate the effectiveness of our approach.
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All authors Rustem Islamov, Grigory Malinovsky, Alexander Gaponov, Aurelien Lucchi, Peter Richtárik, Eduard Gorbunov
Cryptography and Security
CSTS: A Canonical Security Telemetry Substrate for AI-Native Cyber Detection
Abdul Rahman
Cybersecurity data remains fragmented across vendors, formats, schemas, and deployment environments, forcing AI and analytics programs to spend disproportionate effort on ingestion, normalization, and brittle source-specific engineering. This paper introduces the Canonical Security Telemetry Substrate (CSTS), a canonical, AI-ready telemetry foundation designed to harmonize heterogeneous cyber data into a common representation over persistent entities, typed relations, events, temporal state, and provenance. CSTS is intended to move cybersecurity analytics beyond ad hoc record normalization toward a reusable substrate that supports anomaly detection, graph learning,
forecasting, behavior-based modeling, and agentic cyber AI. We formalize the core design principles of CSTS, define its representational components, and explain how it preserves source-specific nuance through explicit mappings and extensible metadata while still enabling portable downstream inference. We further position CSTS as a cloud-agnostic and deployment-agnostic substrate suitable for on-prem, hybrid, and multi-cloud environments. The result is a unifying telemetry model that reduces the blue-collar burden of cyber data engineering and creates a clearer path to scalable, interoperable, and model-agnostic cyber AI.
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Cryptography and Security
Targeted Adversarial Traffic Generation : Black-box Approach to Evade Intrusion Detection Systems in IoT Networks
Islam Debicha, Tayeb Kenaza, Ishak Charfi et al. (+3 more)
The integration of machine learning (ML)
algorithms into Internet of Things (IoT) applications has introduced significant advantages alongside vulnerabilities to
adversarial attacks, especially within IoT-based intrusion detection systems (IDS). While theoretical
adversarial attacks have been extensively studied, practical implementation constraints have often been overlooked. This research addresses this gap by evaluating the feasibility of evasion attacks on IoT network-based IDSs, employing a novel black-box
adversarial attack. Our study aims to bridge theoretical vulnerabilities with real-world applicability, enhancing understanding and defense against sophisticated threats in modern IoT ecosystems. Additionally, we propose a defense scheme tailored to mitigate the impact of evasion attacks, thereby reinforcing the resilience of ML-based IDSs. Our findings demonstrate successful evasion attacks against IDSs, underscoring their susceptibility to advanced techniques. In contrast, we proposed a defense mechanism that exhibits robust performance by effectively detecting the majority of
adversarial traffic, showcasing promising outcomes compared to current state-of-the-art defenses. By addressing these critical cybersecurity challenges, our research contributes to advancing IoT security and provides insights for developing more resilient IDS.
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All authors Islam Debicha, Tayeb Kenaza, Ishak Charfi, Salah Mosbah, Mehdi Sehaki, Jean-Michel Dricot
Cryptography and Security
An Experimental Study of Machine Learning-Based Intrusion Detection for OPC UA over Industrial Private 5G Networks
Song Son Ha, Kunal Singh, Florian Foerster et al. (+4 more)
Industrial deployments increasingly rely on Open Platform Communications Unified Architecture (OPC UA) as a secure and platform-independent communication protocol, while private Fifth Generation (5G) networks provide low-latency and high-reliability connectivity for modern automation systems. However, their combination introduces new attack surfaces and traffic characteristics that remain insufficiently understood, particularly with respect to machine learning-based intrusion detection systems (ML-based IDS). This paper presents an experimental study on detecting cyberattacks against OPC UA applications operating over an operational private 5G network. Multiple attack scenarios are executed, and OPC UA traffic is captured and enriched with statistical flow-, packet-, and protocol-aware features. Several supervised ML models are trained and evaluated to distinguish benign and malicious traffic. The results demonstrate that the proposed ML-based IDS achieves high detection performance for a representative set of OPC UA-specific attack scenarios over an operational private 5G network.
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All authors Song Son Ha, Kunal Singh, Florian Foerster, Henry Beuster, Tim Kittel, Dominik Merli, Gerd Scholl
Cryptography and Security
Canonical Byte-String Encoding for Finite-Ring Cryptosystems
Kyrylo Riabov and Serhii Kryvyi
Ring-mapping protocols need a canonical byte-to-residue layer before any algebraic encryption step can begin. This paper isolates that layer and presents the base-m length codec, a canonical map from byte strings of length less than 2^64 to lists of residues modulo m. The encoder builds on and adapts an rANS-based system proposed by Duda. Decoding is exact for all
moduli satisfying the paper's parameter bounds. Because the encoding carries the byte length in its fixed-width header, decoding is also tolerant to appended valid suffix digits. The paper is accompanied by a Rust implementation of the described protocol, a Lean 4 formalization of the abstract codec with machine-checked proofs, and performance
benchmarks. The Lean 4 formalization establishes fixed-width prefix inversion and payload-state bounds below 2^64, stream-level roundtrip correctness, and that every emitted symbol is a valid residue modulo m. We conclude with a complexity analysis and a discussion of practical considerations arising in real-world use of the codec.
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Cryptography and Security
What a Mesh: Formal Security Analysis of WPA3 SAE Wireless Authentication
Roberto Metere, Mario Lilli, Luca Arnaboldi et al. (+1 more)
The latest Wi-Fi security standard, IEEE 802.11, includes a secure authentication protocol called SAE, whose use is mandatory for WPA3-Personal networks. The protocol is specified at two separate but linked levels: a traditional cryptographic description of the communication logic between network devices, and a state machine description that realises the former in each single device. Current formal verification efforts focus mainly on communication logic. We present detailed formal models of the protocol at both levels, provide precise specifications of its security properties, and analyse machine-checked proofs in ProVerif and ASMETA. The integrated analysis of the above two models is particularly novel, enabling us to identify and address several issues in the current IEEE 802.11 specification more thoroughly than would have been possible otherwise, leading to several official revisions of the standard.
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All authors Roberto Metere, Mario Lilli, Luca Arnaboldi, Elvinia Riccobene
Cryptography and Security
Security Barriers to Trustworthy AI-Driven Cyber Threat Intelligence in Finance: Evidence from Practitioners
Emir Karaosman, Advije Rizvani and Irdin Pekaric
Financial institutions face increasing cyber risk while operating under strict regulatory oversight. To manage this risk, they rely heavily on Cyber Threat Intelligence (CTI) to inform detection, response, and strategic security decisions. Artificial intelligence (AI) is widely suggested as a means to strengthen CTI. However, evidence of trustworthy production use in finance remains limited. Adoption depends not only on predictive performance, but also on governance, integration into security workflows and analyst trust. Thus, we examine how AI is used for CTI in practice within financial institutions and what barriers prevent trustworthy deployment. We report a mixed-methods, user-centric study combining a CTI-finance-focused systematic literature review, semi-structured interviews, and an exploratory survey. Our review screened 330 publications (2019-2025) and retained 12 finance-relevant studies for analysis; we further conducted six interviews and collected 14 survey responses from banks and consultancies. Across research and practice, we identify four recurrent socio-technical failure modes that hinder trustworthy AI-driven CTI: (i) shadow use of public AI tools outside institutional controls, (ii) license-first enablement without operational integration, (iii) attacker-perception gaps that limit
adversarial threat modeling, and (iv) missing security for the AI models themselves, including limited monitoring, robustness evaluation and audit-ready evidence. Survey results provide additional insights: 71.4% of respondents expect AI to become central within five years, 57.1% report infrequent current use due to interpretability and assurance concerns and 28.6% report direct encounters with
adversarial risks. Based on these findings, we derive three security-oriented operational safeguards for AI-enabled CTI deployments.
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Cryptography and Security
Not All Tokens Are Created Equal: Query-Efficient Jailbreak Fuzzing for LLMs
Wenyu Chen, Xiangtao Meng, Chuanchao Zang et al. (+6 more)
Large
Language Models(LLMs) are widely deployed, yet are vulnerable to jailbreak
prompts that elicit policy-violating outputs. Although prior studies have uncovered these risks, they typically treat all
tokens as equally important during
prompt mutation, overlooking the varying contributions of individual
tokens to triggering model refusals. Consequently, these attacks introduce substantial redundant searching under query-constrained scenarios, reducing attack efficiency and hindering comprehensive vulnerability assessment. In this work, we conduct a
token-level analysis of refusal behavior and observe that
token contributions are highly skewed rather than uniform. Moreover, we find strong cross-model consistency in refusal tendencies, enabling the use of a surrogate model to estimate
token-level contributions to the target model's refusals. Motivated by these findings, we propose TriageFuzz, a
token-aware jailbreak fuzzing framework that adapts the fuzz testing approach with a series of customized designs. TriageFuzz leverages a surrogate model to estimate the contribution of individual
tokens to refusal behaviors, enabling the identification of sensitive regions within the
prompt. Furthermore, it incorporates a refusal-guided evolutionary strategy that adaptively weights candidate
prompts with a lightweight scorer to steer the
evolution toward bypassing safety constraints. Extensive experiments on six open-source LLMs and three commercial APIs demonstrate that TriageFuzz achieves comparable attack success rates (ASR) with significantly reduced query costs. Notably, it attains a 90% ASR with over 70% fewer queries compared to baselines. Even under an extremely restrictive budget of 25 queries, TriageFuzz outperforms existing methods, improving ASR by 20-40%.
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All authors Wenyu Chen, Xiangtao Meng, Chuanchao Zang, Li Wang, Xinyu Gao, Jianing Wang, Peng Zhan, Zheng Li, Shanqing Guo
Cryptography and Security
On the Vulnerability of FHE Computation to Silent Data Corruption
Jianan Mu, Ge Yu, Zhaoxuan Kan et al. (+6 more)
Fully Homomorphic Encryption (FHE) is rapidly emerging as a promising foundation for
privacy-preserving cloud services, enabling computation directly on encrypted data. As FHE implementations mature and begin moving toward practical deployment in domains such as secure finance, biomedical analytics, and
privacy-preserving AI, a critical question remains insufficiently explored: how reliable is FHE computation on real hardware? This question is especially important because, compared with plaintext computation, FHE incurs much higher computational overhead, making it more susceptible to transient hardware faults. Moreover, data corruptions are likely to remain silent: the FHE service has no access to the underlying plaintext, causing unawareness even though the corresponding decrypted result has already been corrupted. To this end, we conduct a comprehensive evaluation of SDCs in FHE ciphertext computation. Through large-scale fault-injection experiments, we characterize the vulnerability of FHE to transient faults, and through a theoretical analysis of error-propagation behaviors, we gain deeper algorithmic insight into the mechanisms underlying this vulnerability. We further assess the effectiveness of different fault-tolerance mechanisms for mitigating these faults.
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All authors Jianan Mu, Ge Yu, Zhaoxuan Kan, Song Bian, Liang Kong, Zizhen Liu, Cheng Liu, Jing Ye, Huawei Li
Cryptography and Security
The Power of Power Codes: New Classes of Easy Instances for the Linear Equivalence Problem
Michele Battagliola, Anna-Lena Horlemann, Abhinaba Mazumder et al. (+4 more)
Given two linear codes, the Linear Equivalence Problem (LEP) asks to find (if it exists) a linear isometry between them; as a special case, we have the Permutation Equivalence Problem (PEP), in which isometries must be permutations. LEP and PEP have recently gained renewed interest as the security foundations for several post-
quantum schemes, including LESS. A recent paper has introduced the use of the Schur product to solve PEP, identifying many new easy-to-solve instances. In this paper, we extend this result to LEP. In particular, we generalize the approach and rely on the more general notion of power codes. Combining it with Frobenius
automorphisms and Hermitian hulls, we identify many classes of easy LEP instances. To the best of our knowledge, this is the first work exploiting algebraic weaknesses for LEP. Finally we show an improved reduction to PEP whenever the coefficients of the monomial
matrix are in a subgroup of the multiplicative group of the finite field.
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All authors Michele Battagliola, Anna-Lena Horlemann, Abhinaba Mazumder, Rocco Mora, Paolo Santini, Michael Schaller, Violetta Weger
Cryptography and Security
Gyokuro: Source-assisted Private Membership Testing using Trusted Execution Environments
Yoshimichi Nakatsuka, Nicolas Dutly, Kari Kostiainen et al. (+1 more)
Private Membership Testing (PMT) protocols enable clients to verify whether a certain data item is included in a database without revealing the item to the database operator or other external parties. This paper examines Source-assisted PMT (SPMT), in which clients leverage compact data source-provided information issued when the data item is first submitted to the database. SPMT is relevant in applications such as certificate transparency and supply-chain
auditing; yet, designing an approach that is efficient, scalable, and
privacy-preserving remains a challenge. This work presents Gyokuro, which takes a different approach to conventional membership testing schemes. Instead of requesting the server to produce a proof attesting that a certain data item exists in the database, we leverage Trusted Execution Environments (TEEs) to produce proofs demonstrating that the server has made enough progress to add the data item to the database. With the help of existing monitoring services, clients can infer that no items have been removed from the database. This allows Gyokuro to provide strong
privacy guaranties and achieve high efficiency, as a client's membership testing query does not include any information regarding their interests, and eliminates the need for complex and inefficient protection mechanisms. Additionally, this approach enables membership testing on large-scale databases, since the communication and computation required are independent of the database size. Our evaluations show practical feasibility, achieving 7 ms membership testing latency and throughput of around 1400 requests/sec/core.
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All authors Yoshimichi Nakatsuka, Nicolas Dutly, Kari Kostiainen, Srdjan Capkun
Cryptography and Security
PRETTINESS – Privacy pResErving aTTrIbute maNagEment SyStem
Jelizaveta Vakarjuk and Alisa Pankova
European Digital Identity (EUDI) Wallet aims to provide end users with a way to get attested credentials from issuers, and present them to different relying parties. An important property mentioned in the regulatory frameworks is the possibility to revoke a previously issued credential. While it is possible to issue a short-lived credential, in some cases it may be inconvenient, and a separate revocation service which allows to revoke a credential at any time may be necessary. In this work, we propose a full end-to-end description of a generic credential revocation system, which technically relies on a single server and secure transmission channels between parties. We prove security of the proposed revocation functionality in the universal composability model, and estimate its efficiency based on a proof-of-concept implementation.
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Cryptography and Security
Privacy-Aware Smart Cameras: View Coverage via Socially Responsible Coordination
Chuhao Qin, Lukas Esterle and Evangelos Pournaras
Coordination of view coverage via
privacy-aware smart cameras is key to a more socially responsible urban intelligence. Rather than maximizing view coverage at any cost or over relying on expensive cryptographic techniques, we address how cameras can coordinate to legitimately monitor public spaces while excluding
privacy-sensitive regions by design. This article proposes a decentralized framework in which interactive smart cameras coordinate to autonomously select their orientation via collective learning, while eliminating
privacy violations via soft and hard constraint satisfaction. The approach scales to hundreds up to thousands of cameras without any centralized control. Experimental evidence shows 18.42% higher coverage efficiency and 85.53% lower
privacy violation than baselines and other state-of-the-art approaches. This significant advance further unravels practical guidelines for operators and policymakers: how the field of view, spatial placement, and budget of cameras operating by ethically-aligned artificial intelligence jointly influence coverage efficiency and
privacy protection in large-scale and sensitive urban environments.
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