Cryptography and Security
Grant, Verify, Revoke: A User-Centric Pattern for Blockchain Compliance
Supriya Khadka and Sanchari Das
In decentralized web applications, users face an inherent conflict between public verifiability and personal
privacy. To participate in regulated on-chain services, users must currently disclose sensitive identity documents to centralized intermediaries, permanently linking real-world identities to public transaction histories. This binary choice between total
privacy loss or total exclusion strips users of agency and exposes them to persistent surveillance. In this work, we introduce a Selective Disclosure Framework designed to restore user sovereignty by decoupling eligibility verification from identity revelation. We present ZK-Compliance, a prototype that leverages browser-based zero-knowledge proofs to shift the interaction model, enabling users to prove specific attributes (e.g., "I am over 18") locally without revealing the underlying data. We implement a user-governed Grant, Verify, Revoke lifecycle that transforms the user's mental model of compliance from a permanent data handover into a dynamic, revocable authorization session. Our evaluation shows that client-side proof generation takes under 200ms, enabling a seamless interactive experience on commodity hardware. This work provides early evidence that regulatory compliance need not come at the cost of user
privacy or autonomy.
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Cryptography and Security
How Vulnerable Are AI Agents to Indirect Prompt Injections? Insights from a Large-Scale Public Competition
Mateusz Dziemian, Maxwell Lin, Xiaohan Fu et al. (+28 more)
LLM based
agents are increasingly deployed in high stakes settings where they process external data sources such as emails, documents, and code repositories. This creates exposure to indirect
prompt injection attacks, where
adversarial instructions embedded in external content manipulate
agent behavior without user awareness. A critical but underexplored dimension of this threat is concealment: since users tend to observe only an
agent's final response, an attack can conceal its existence by presenting no clue of compromise in the final user facing response while successfully executing harmful actions. This leaves users unaware of the manipulation and likely to accept harmful outcomes as legitimate. We present findings from a large scale public red teaming competition evaluating this dual objective across three
agent settings: tool calling, coding, and computer use. The competition attracted 464 participants who submitted 272000 attack attempts against 13 frontier models, yielding 8648 successful attacks across 41 scenarios. All models proved vulnerable, with attack success rates ranging from 0.5% (Claude Opus 4.5) to 8.5% (Gemini 2.5 Pro). We identify universal attack strategies that transfer across 21 of 41 behaviors and multiple model families, suggesting fundamental weaknesses in instruction following architectures. Capability and robustness showed weak correlation, with Gemini 2.5 Pro exhibiting both high capability and high vulnerability. To address
benchmark saturation and obsoleteness, we will endeavor to deliver quarterly updates through continued red teaming competitions. We open source the competition environment for use in evaluations, along with 95 successful attacks against Qwen that did not transfer to any closed source model. We share model-specific attack data with respective frontier labs and the full
dataset with the UK AISI and US CAISI to support robustness research.
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All authors Mateusz Dziemian, Maxwell Lin, Xiaohan Fu, Micha Nowak, Nick Winter, Eliot Jones, Andy Zou, Lama Ahmad, Kamalika Chaudhuri, Sahana Chennabasappa, Xander Davies, Lauren Deason, Benjamin L. Edelman, Tanner Emek, Ivan Evtimov, Jim Gust, Maia Hamin, Kat He, Klaudia Krawiecka, Riccardo Patana, Neil Perry, Troy Peterson, Xiangyu Qi, Javier Rando, Zifan Wang, Zihan Wang, Spencer Whitman, Eric Winsor, Arman Zharmagambetov, Matt Fredrikson, Zico Kolter
Cryptography and Security
Remarks on the Relevance of Privacy Expectations for Default Opt-out Settings
Sebastian Zimmeck
Over the past few years an increasing number of states in the US have adopted new
privacy laws. The majority of these laws require compliance with universal opt-out mechanisms (UOOMs), which allow consumers to send legally binding opt-out signals. However, a number of laws generally do not allow UOOMs to be enabled by default. While some laws exempt
privacy-protective software from this prohibition, the exemption does not apply to pre-installed software, e.g., a
privacy-protective web browser bundled with an operating system. The reason for not allowing default opt-out settings for pre-installed software is to ensure that settings reflect consumers' "affirmative, freely given, and unambiguous choice," as, for example, the Colorado
Privacy Act (CPA) is putting it. However, prohibiting vendors of
privacy-protective software from turning on UOOMs by default can force them into committing unfair or deceptive acts or practices under the FTC Act and equivalent state laws. Thus, whether UOOMs can be turned on by default on pre-installed software should depend on consumers'
privacy expectations. For pre-installed software that is creating a reasonable expectation for consumers that their
privacy will be protected, the simple use of such software should be considered a valid choice for enabling UOOMs. In such software a turned-on UOOM is not a "default setting" but rather the software's inherent behavior that a consumer expects and chooses through its use. This interpretation of consumer choice is preferable under the CPA and similar laws as it grounds the notice and choice principle in the
privacy expectations of consumers and enables companies to compete on better
privacy for consumers.
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Cryptography and Security
BadLLM-TG: A Backdoor Defender powered by LLM Trigger Generator
Ruyi Zhang, Heng Gao, Songlei Jian et al. (+2 more)
Backdoor attacks compromise model reliability by using triggers to manipulate outputs. Trigger inversion can accurately locate these triggers via a generator and is therefore critical for
backdoor defense. However, the discrete nature of text prevents existing noise-based trigger generator from being applied to nature
language processing (NLP). To overcome the limitations, we employ the rich knowledge embedded in large
language models (LLMs) and propose a
Backdoor defender powered by LLM Trigger Generator, termed BadLLM-TG. It is optimized through
prompt-driven reinforcement learning, using the victim model's feedback loss as the reward signal. The generated triggers are then employed to mitigate the
backdoor via
adversarial training. Experiments show that our method reduces the attack success rate by 76.2% on average, outperforming the second-best defender by 13.7.
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All authors Ruyi Zhang, Heng Gao, Songlei Jian, Yusong Tan, Haifang Zhou
Cryptography and Security · Cross-listed from stat.AP
Differential Privacy for Network Connectedness Indices
Tom A. Rutter, Yuxin Liu and M. Amin Rahimian
Researchers increasingly use data on social and economic networks to study a range of social science questions, but releasing statistics derived from networks can raise significant
privacy concerns. We show how to release network connectedness indices that quantify assortative mixing across node attributes under edge-adjacent differential
privacy. Standard
privacy techniques perform poorly in this setting both because connectedness indices have high global sensitivity and because a single node's attribute can potentially be an input to connectedness in thousands of
cells, leading to poor composition. Our method, which is straightforward to apply, first adds noise to node attributes, then analytically debiases downstream statistics, and finally applies a second layer of noise to protect the presence or absence of individual edges. We prove consistency and asymptotic normality of our
estimators for both discrete and continuous labels and show our method works well in simulations and on real networks with as few as 200 nodes collected by social scientists.
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Cryptography and Security
Evasive Intelligence: Lessons from Malware Analysis for Evaluating AI Agents
Simone Aonzo, Merve Sahin, Aurélien Francillon et al. (+1 more)
Artificial intelligence (AI) systems are increasingly adopted as tool-using
agents that can plan, observe their environment, and take actions over extended time periods. This
evolution challenges current evaluation practices where the AI models are tested in restricted, fully observable settings. In this article, we argue that evaluations of AI
agents are vulnerable to a well-known failure mode in computer security: malicious software that exhibits benign behavior when it detects that it is being analyzed. We point out how AI
agents can infer the properties of their evaluation environment and adapt their behavior accordingly. This can lead to overly optimistic safety and robustness assessments. Drawing parallels with decades of research on malware sandbox evasion, we demonstrate that this is not a speculative concern, but rather a structural risk inherent to the evaluation of adaptive systems. Finally, we outline concrete principles for evaluating AI
agents, which treat the system under test as potentially
adversarial. These principles emphasize realism, variability of test conditions, and post-deployment reassessment.
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All authors Simone Aonzo, Merve Sahin, Aurélien Francillon, Daniele Perito
Cryptography and Security · Cross-listed from cs.LG
Amplification Effects in Test-Time Reinforcement Learning: Safety and Reasoning Vulnerabilities
Vanshaj Khattar, Md Rafi ur Rashid, Moumita Choudhury et al. (+4 more)
Test-time training (TTT) has recently emerged as a promising method to improve the
reasoning abilities of large
language models (LLMs), in which the model directly learns from test data without access to labels. However, this reliance on test data also makes TTT methods vulnerable to harmful
prompt injections. In this paper, we investigate safety vulnerabilities of TTT methods, where we study a representative self-consistency-based test-time learning method: test-time reinforcement learning (TTRL), a recent TTT method that improves LLM
reasoning by rewarding self-consistency using majority vote as a reward signal. We show that harmful
prompt injection during TTRL amplifies the model's existing behaviors, i.e., safety amplification when the base model is relatively safe, and harmfulness amplification when it is vulnerable to the injected data. In both cases, there is a decline in
reasoning ability, which we refer to as the
reasoning tax. We also show that TTT methods such as TTRL can be exploited adversarially using specially designed "HarmInject"
prompts to force the model to answer jailbreak and
reasoning queries together, resulting in stronger harmfulness amplification. Overall, our results highlight that TTT methods that enhance LLM
reasoning by promoting self-consistency can lead to amplification behaviors and
reasoning degradation, highlighting the need for safer TTT methods.
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All authors Vanshaj Khattar, Md Rafi ur Rashid, Moumita Choudhury, Jing Liu, Toshiaki Koike-Akino, Ming Jin, Ye Wang
Cryptography and Security
TrinityGuard: A Unified Framework for Safeguarding Multi-Agent Systems
Kai Wang, Biaojie Zeng, Zeming Wei et al. (+7 more)
With the rapid development of LLM-based multi-
agent systems (MAS), their significant safety and security concerns have emerged, which introduce novel risks going beyond single
agents or LLMs. Despite attempts to address these issues, the existing literature lacks a cohesive safeguarding system specialized for MAS risks. In this work, we introduce TrinityGuard, a comprehensive safety evaluation and monitoring framework for LLM-based MAS, grounded in the OWASP standards. Specifically, TrinityGuard encompasses a three-tier fine-grained risk taxonomy that identifies 20 risk types, covering single-
agent vulnerabilities, inter-
agent communication threats, and system-level emergent hazards. Designed for scalability across various MAS structures and platforms, TrinityGuard is organized in a trinity manner, involving an MAS abstraction layer that can be adapted to any MAS structures, an evaluation layer containing risk-specific test modules, alongside runtime monitor
agents coordinated by a unified LLM Judge Factory. During Evaluation, TrinityGuard executes curated attack probes to generate detailed vulnerability reports for each risk type, where monitor
agents analyze structured execution traces and issue real-time alerts, enabling both pre-development evaluation and runtime monitoring. We further formalize these safety metrics and present detailed case studies across various representative MAS examples, showcasing the versatility and reliability of TrinityGuard. Overall, TrinityGuard acts as a comprehensive framework for evaluating and monitoring various risks in MAS, paving the way for further research into their safety and security.
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All authors Kai Wang, Biaojie Zeng, Zeming Wei, Chang Jin, Hefeng Zhou, Xiangtian Li, Chao Yang, Jingjing Qu, Xingcheng Xu, Xia Hu
Cryptography and Security
SFCoT: Safer Chain-of-Thought via Active Safety Evaluation and Calibration
Yu Pan, Wenlong Yu, Tiejun Wu et al. (+4 more)
Large
language models (LLMs) have demonstrated remarkable capabilities in complex
reasoning tasks. However, they remain highly susceptible to jailbreak attacks that undermine their safety
alignment. Existing defense mechanisms typically rely on post hoc filtering applied only to the final output, leaving intermediate
reasoning steps unmonitored and vulnerable to
adversarial manipulation. To address this gap, this paper proposes a SaFer Chain-of-Thought (SFCoT) framework, which proactively evaluates and calibrates potentially unsafe
reasoning steps in real time. SFCoT incorporates a three-tier safety scoring system alongside a multi-perspective consistency verification mechanism, designed to detect potential risks throughout the
reasoning process. A dynamic intervention module subsequently performs targeted calibration to redirect
reasoning trajectories toward safe outcomes. Experimental results demonstrate that SFCoT reduces the attack success rate from $58.97\%$ to $12.31\%$, demonstrating it as an effective and efficient LLM safety enhancement method without a significant decline in general performance.
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All authors Yu Pan, Wenlong Yu, Tiejun Wu, Xiaohu Ye, Qiannan Si, Guangquan Xu, Bin Wu
Cryptography and Security · Cross-listed from cs.SE
SKILLS: Structured Knowledge Injection for LLM-Driven Telecommunications Operations
Ivo Brett
As telecommunications operators accelerate adoption of AI-enabled automation, a practical question remains unresolved: can general-purpose large
language model (LLM)
agents reliably execute telecom operations workflows through real API interfaces, or do they require structured domain guidance? We introduce SKILLS (Structured Knowledge Injection for LLM-driven Service Lifecycle operations), a
benchmark framework comprising 37 telecom operations scenarios spanning 8 TM Forum Open API domains (TMF620, TMF621, TMF622, TMF628, TMF629, TMF637, TMF639, TMF724). Each scenario is grounded in live mock API servers with seeded production-representative data, MCP tool interfaces, and deterministic evaluation rubrics combining response content checks, tool-call verification, and database state assertions. We evaluate open-weight models under two conditions: baseline (generic
agent with tool access but no domain guidance) and with-skill (
agent augmented with a portable SKILL.md document encoding workflow logic, API patterns, and business rules). Results across 5 open-weight model conditions and 185 scenario-runs show consistent skill lift across all models. MiniMax M2.5 leads (81.1% with-skill, +13.5pp), followed by Nemotron 120B (78.4%, +18.9pp), GLM-5 Turbo (78.4%, +5.4pp), and Seed 2.0 Lite (75.7%, +18.9pp).
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Cryptography and Security
Unsupervised Cross-Protocol Anomaly Analysis in Mobile Core Networks via Multi-Embedding Models Consensus
Aayush Garg and Orlando Amaral Cejas
Mobile core networks rely on several signalling protocols in parallel, such as SS7, Diameter, and GTP, so many security-relevant problems become visible only when their interactions are analyzed jointly. At the same time, labeled examples of real attacks and cross-protocol misconfigurations are scarce, which complicates supervised detection. We therefore study unsupervised cross-protocol anomaly analysis on fused representations that combine SS7, Diameter, and GTP signalling. For each subscriber, we aggregate messages into per-minute fused records, serialize each record as text, embed it with several models, and apply unsupervised anomaly detection. We then assign each record a consensus score equal to the number of
embedding models that flag it as anomalous. For evaluation, we generate cross-protocol-plausible synthetic anomalies by swapping one field group at a time between pairs of records, preserving per-message validity while making the fused view contradictory. On 219,294 fused records, 44.15% are flagged by at least one model, but only 0.97% reach full agreement across all six. Higher consensus is strongly associated with synthetic records, where for k=1-4 the odds that a flagged record is synthetic are hundreds of times greater than for original records, and for k>=5 all flagged records are synthetic, with extremely small p-values. Cosine distances between synthetic and original records also increase with consensus, suggesting clearer separation in
embedding space. These results support the use of multi-
embedding consensus to prioritize a much smaller set of candidate cross-protocol inconsistencies for further inspection.
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Cryptography and Security
Comparative Analysis of SRAM PUF Temperature Susceptibility on Embedded Systems
Martina Zeinzinger, Josef Langer, Florian Eibensteiner et al. (+4 more)
An SRAM Physical Unclonable Function (PUF) can distinguish SRAM modules by analyzing the inherent randomness of their start-up behavior. However, the effectiveness of this technique varies depending on the design and fabrication of the SRAM module. This study compares two similar microcontrollers, both equipped with on-chip SRAM, to determine which device produces a better SRAM PUF. Both microcontrollers are programmed with an identical SRAM PUF authentication routine and tested under varying ambient temperatures (ranging from 10 {\deg}C to 50 {\deg}C) to evaluate the impact of temperature on SRAM PUF performance. One embedded SRAM works significantly better than the other, even though the two models are closely related. The presented results can be used early in the design process to compare arbitrary on-chip SRAM models and see which is best suited for implementing an SRAM PUF.
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All authors Martina Zeinzinger, Josef Langer, Florian Eibensteiner, Phillip Petz, Lucas Drack, Daniel Dorfmeister, Rudolf Ramler
Cryptography and Security · Cross-listed from cs.LG
Ye Wang, Jing Liu and Toshiaki Koike-Akino
The safety and reliability of
vision-
language models (VLMs) are a crucial part of deploying trustworthy agentic AI systems. However, VLMs remain vulnerable to jailbreaking attacks that undermine their safety
alignment to yield harmful outputs. In this work, we extend the Randomized
Embedding Smoothing and
Token Aggregation (RESTA) defense to VLMs and evaluate its performance against the JailBreakV-28K
benchmark of multi-modal jailbreaking attacks. We find that RESTA is effective in reducing attack success rate over this diverse corpus of attacks, in particular, when employing directional
embedding noise, where the injected noise is aligned with the original
token embedding vectors. Our results demonstrate that RESTA can contribute to securing VLMs within agentic systems, as a lightweight, inference-time defense layer of an overall security framework.
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Cryptography and Security
vCause: Efficient and Verifiable Causality Analysis for Cloud-based Endpoint Auditing
Qiyang Song, Qihang Zhou, Xiaoqi Jia et al. (+5 more)
In cloud-based endpoint
auditing, security administrators often rely on the cloud to perform causality analysis over log-derived versioned provenance graphs to investigate suspicious attack behaviors. However, the cloud may be distrusted or compromised by attackers, potentially manipulating the final causality analysis results. Consequently, administrators may not accurately understand attack behaviors and fail to implement effective countermeasures. This risk underscores the need for a defense scheme to ensure the integrity of causality analysis. While existing tamper-evident logging schemes and trusted execution environments show promise for this task, they are not specifically designed to support causality analysis and thus face inherent security and efficiency limitations. This paper presents vCause, an efficient and verifiable causality analysis system for cloud-based endpoint
auditing. vCause integrates two authenticated data structures: a graph accumulator and a verifiable provenance graph. The data structures enable validation of two critical steps in causality analysis: (i) querying a point-of-interest node on a versioned provenance graph, and (ii) identifying its causally related components. Formal security analysis and experimental evaluation show that vCause can achieve secure and verifiable causality analysis with only <1% computational overhead on endpoints and 3.36% on the cloud.
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All authors Qiyang Song, Qihang Zhou, Xiaoqi Jia, Zhenyu Song, Wenbo Jiang, Heqing Huang, Yong Liu, Dan Meng
Cryptography and Security · Cross-listed from math.NT
Infinite families of APN permutations in constrained trivariate classes over $\mathbb{F}_{2^m}$
Daniele Bartoli and Pantelimon Stanica
We study trivariate permutation
polynomials over $\mathbb{F}_{2^{m}}$ extending two APN permutation families of Li–Kaleyski (IEEE Trans. Inform. Theory, 2024) by allowing the scalar parameter to vary over $\mathbb{F}_{2^m}^*$. For \[ G_a(x,y,z)=(x^{q+1}+ax^qz+yz^q,\; x^qz+y^{q+1},\; xy^q+ay^qz+z^{q+1}), \] where $a\in\mathbb{F}_{2^m}^*$, $q=2^i$, $\gcd(i,m)=1$, and $m$ is odd, we prove that $G_a$ is a permutation if and only if an associated univariate
polynomial has no root in $\mathbb{F}_{2^m}^*$, and that this condition is also equivalent to $G_a$ being APN. Hence, writing $d=q^2+q+1$, at least \[ \frac{2^m+1-(d-1)(d-2)2^{m/2}-d}{d} \] values of $a$ yield APN permutations $G_a$. In the binary case $q=2$, we show that $a=1$ is good whenever $7\nmid m$, recovering the Li–Kaleyski family. For the second family \[ H_a(x,y,z)=(x^{q+1}+axy^q+yz^q,\; xy^q+z^{q+1},\; x^qz+y^{q+1}+ay^qz), \] we obtain the same root criterion and prove that its defining
polynomial is root-equivalent to that of $G_a$. Thus the same parameters $a$ give APN permutations in both families. We also prove strong inequivalence results. First, $G_a$ (resp.\ $H_a$) is diagonally equivalent to $G_1$ (resp.\ $H_1$) if and only if $a^{q^2+q+1}=1$; moreover, for $m>4$, $m\neq 6$, and $7\nmid m$, diagonal non-equivalence implies CCZ non-equivalence by the monomial restriction
theorem of Shi et al.\ (DCC, 2025). In particular, when $q=2$ and $7\nmid m$, every good $a\neq 1$ gives APN permutations CCZ-inequivalent to Li–Kaleyski. Second, for the same range of $m$, no $G_a$ is CCZ-equivalent to any $H_b$. Hence these constructions yield two genuinely new, mutually inequivalent families of APN permutations on $\mathbb{F}_{2^{3m}}$.
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Cryptography and Security
From Storage to Steering: Memory Control Flow Attacks on LLM Agents
Zhenlin Xu, Xiaogang Zhu, Yu Yao et al. (+2 more)
Modern agentic systems allow Large
Language Model (LLM)
agents to tackle complex tasks through extensive tool usage, forming structured control flows of tool selection and execution. Existing security analyses often treat these control flows as ephemeral, one-off sessions, overlooking the persistent influence of
memory. This paper identifies a new threat from
Memory Control Flow Attacks (MCFA) that
memory can dominate the control flow, forcing unintended tool usage even against explicit user instructions and inducing persistent behavioral deviations across tasks. To understand the impact of this vulnerability, we further design MEMFLOW, an automated evaluation framework that systematically identifies and quantifies MCFA across heterogeneous tasks and long interaction horizons. To evaluate MEMFLOW, we attack state-of-the-art LLMs, including GPT-5 mini, Claude Sonnet 4.5 and Gemini 2.5 Flash on real-world tools from two major LLM
agent development frameworks, LangChain and LlamaIndex. The results show that in general over 90% of trials are vulnerable to MCFA even under strict safety constraints, highlighting critical security risks that demand immediate
attention.
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All authors Zhenlin Xu, Xiaogang Zhu, Yu Yao, Minhui Xue, Yiliao Song
Cryptography and Security · Cross-listed from cs.DB
DP-S4S: Accurate and Scalable Select-Join-Aggregate Query Processing with User-Level Differential Privacy
Yuan Qiu, Xiaokui Xiao and Yin Yang
Answering Select-Join-Aggregate queries with DP is a fundamental problem with important applications in various domains. The current SOTA methods ensure user-level DP (i.e., the adversary cannot infer the presence or absence of any given individual user with high confidence) and achieve instance-optimal accuracy on the query results. However, these solutions involve solving expensive optimization programs, which may incur prohibitive computational overhead for large databases. One promising direction to achieve scalability is through sampling, which provides a tunable trade-off between result utility and computational costs. However, applying sampling to differentially private SJA processing is a challenge for two reasons. First, it is unclear what to sample, in order to achieve the best accuracy within a given computational budget. Second, prior solutions were not designed with sampling in mind, and their mathematical tool chains are not sampling-friendly. To our knowledge, the only known solution that applies sampling to private SJA processing is S&E, a recent proposal that (i) samples users and (ii) combines sampling directly with existing solutions to enforce DP. We show that both are suboptimal designs; consequently, even with a relatively high sample rate, the error incurred by S&E can be 10x higher than the underlying DP mechanism without sampling. Motivated by this, we propose Differentially Private Sampling for Scale (DP-S4S), a novel mechanism that addresses the above challenges by (i) sampling aggregation units instead of users, and (ii) laying the mathematical foundation for SJA processing under RDP, which composes more easily with sampling. Further, DP-S4S can answer both scalar and vector SJA queries. Extensive experiments on real data demonstrate that DP-S4S enables scalable SJA processing on large
datasets under user-level DP, while maintaining high result utility.
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Cryptography and Security
Rethinking LLM Watermark Detection in Black-Box Settings: A Non-Intrusive Third-Party Framework
Zhuoshang Wang, Yubing Ren, Yanan Cao et al. (+3 more)
While watermarking serves as a critical mechanism for LLM provenance, existing secret-key schemes tightly couple detection with injection, requiring access to keys or provider-side scheme-specific detectors for verification. This dependency creates a fundamental barrier for real-world governance, as independent
auditing becomes impossible without compromising model security or relying on the opaque claims of service providers. To resolve this dilemma, we introduce TTP-Detect, a pioneering black-box framework designed for non-intrusive, third-party watermark verification. By decoupling detection from injection, TTP-Detect reframes verification as a relative hypothesis testing problem. It employs a proxy model to amplify watermark-relevant signals and a suite of complementary relative measurements to assess the
alignment of the query text with watermarked distributions. Extensive experiments across representative watermarking schemes,
datasets and models demonstrate that TTP-Detect achieves superior detection performance and robustness against diverse attacks.
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All authors Zhuoshang Wang, Yubing Ren, Yanan Cao, Fang Fang, Xiaoxue Li, Li Guo
Cryptography and Security
Fine-tuning RoBERTa for CVE-to-CWE Classification: A 125M Parameter Model Competitive with LLMs
Nikita Mosievskiy
We present a fine-tuned RoBERTa-base classifier (125M parameters) for mapping Common Vulnerabilities and Exposures (CVE) descriptions to Common Weakness Enumeration (CWE) categories. We construct a large-scale training
dataset of 234,770 CVE descriptions with AI-refined CWE labels using Claude Sonnet 4.6, and agreement-filtered evaluation sets where NVD and AI labels agree. On our held-out test set (27,780 samples, 205 CWE classes), the model achieves 87.4% top-1 accuracy and 60.7% Macro F1 – a +15.5 percentage-point Macro F1 gain over a TF-IDF baseline that already reaches 84.9% top-1, demonstrating the model's advantage on rare weakness categories. On the external CTI-Bench
benchmark (NeurIPS 2024), the model achieves 75.6% strict accuracy (95% CI: 72.8-78.2%) – statistically indistinguishable from Cisco Foundation-Sec-8B-
Reasoning (75.3%, 8B parameters) at 64x fewer parameters. We release the
dataset, model, and training code.
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Cryptography and Security
Architecture-Agnostic Feature Synergy for Universal Defense Against Heterogeneous Generative Threats
Bingxue Zhang, Yang Gao, Feida Zhu et al. (+2 more)
Generative AI deployment poses unprecedented challenges to content safety and
privacy. However, existing defense mechanisms are often tailored to specific architectures (e.g.,
Diffusion Models or GANs), creating fragile "defense silos" that fail against heterogeneous generative threats. This paper identifies a fundamental optimization barrier in naive pixel-space ensemble strategies: due to divergent objective functions, pixel-level gradients from heterogeneous generators become statistically orthogonal, causing destructive interference. To overcome this, we observe that despite disparate low-level mechanisms, high-level feature representations of generated content exhibit
alignment across architectures. Based on this, we propose the Architecture-Agnostic Targeted Feature Synergy (ATFS) framework. By introducing a target guidance image, ATFS reformulates multi-model defense as a unified feature space
alignment task, enabling intrinsic gradient
alignment without complex rectification. Extensive experiments show ATFS achieves SOTA protection in heterogeneous scenarios (e.g.,
Diffusion+GAN). It converges rapidly, reaching over 90% performance within 40 iterations, and maintains strong attack potency even under tight perturbation budgets. The framework seamlessly extends to unseen architectures (e.g., VQ-VAE) by switching the feature extractor, and demonstrates robust resistance to JPEG compression and scaling. Being computationally efficient and lightweight, ATFS offers a viable pathway to dismantle defense silos and enable universal generative security. Code and models are open-sourced for reproducibility.
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All authors Bingxue Zhang, Yang Gao, Feida Zhu, Yanyan Shen, Yang Shi
Cryptography and Security · Cross-listed from quant-ph
Security-enhanced Blockchain with Twin-Field Quantum Key Distribution: A Physical Layer enabled Architecture
Xuan Li, Yun Mao and Ying Guo
Quantum computing provides a feasible multi-layered security challenge to classical blockchain networks.
Quantum blockchains that rely on
quantum key distribution (QKD) to establish secure channels can address this feasible threat. Whereas, there are still architecture limitations to practical security resulted in the measurement devices while implementing the QKD-secured blockchains in physical layer. This paper presents a
quantum-classical hybrid architecture in a distributed blockchain to address the connectivity and distance limitations of the blockchain-embedded
quantum networks. A decoupled architecture is designed felicitously so that it pairs a linearly scalable measurement-device-independent (MDI) physical layer with a decentralized consensus. It can optimize the complexity of infrastructure from quadratic to linear scaling, ascribed to leveraging the twin-field (TF) QKD protocol with the MDI-structurized
star topology. Additionally, the dual-key stratification strategy transforms symmetric information-theoretic security into publicly auditable forward-secret blockchain evidence. This architecture can integrate the exact information-theoretic security (ITS) with distributed consensus mechanisms, allowing the scalable system to overcome the potential rate-loss limits inherent in classical security-weakened blockchains.
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Cryptography and Security
P$^2$RAG: Efficient Privacy-Preserving RAG Service Supporting Arbitrary Top-$k$ Retrieval
Yulong Ming, Mingyue Wang, Jijia Yang et al. (+4 more)
Retrieval-Augmented Generation (RAG) enables large
language models to use external knowledge, but outsourcing the RAG service raises
privacy concerns for both data owners and users.
Privacy-preserving RAG systems address these concerns by performing secure top-$k$
retrieval, which is typically implemented using secure sorting to identify relevant documents. However, existing systems face challenges supporting arbitrary $k$ due to their inability to change $k$, new security issues, and in particular, efficiency degradation with large $k$. This is a significant limitation because applications such as finance, law, and healthcare require a $k$ that is large enough to cause huge overhead for existing systems. Also, modern long-context models generally achieve higher accuracy with larger
retrieval sets. We propose P$^2$RAG, an efficient
privacy-preserving RAG service that supports arbitrary top-$k$
retrieval. Unlike existing systems, P$^2$RAG avoids sorting candidate documents. Instead, it uses an interactive bisection method to determine the set of top-$k$ documents. For security, P$^2$RAG uses secret sharing on two semi-honest non-colluding servers to protect the data owner's database and the user's
prompt. It enforces restrictions and verification to defend against malicious users and tightly bounds the information leakage of the database. The experiments show that P$^2$RAG is 3–300$\times$ faster than the state-of-the-art PRAG for $k = 16$–$1024$.
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All authors Yulong Ming, Mingyue Wang, Jijia Yang, Jie Xu, Zihan Wu, Cong Wang, Xiaohua Jia