Research paper AgentLSD: Evaluating AI Security Agents Under Adversarial Task Contamination
Matteo Golinelli1, Idilio Drago2, Matteo Boffa3, Francesco Bergadano2, Bruno Crispo1
- 1University of Trento
- 2University of Turin
- 3Politecnico di Torino
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AI agents for security inspect web pages, source code, logs, configuration files, and command outputs. These environments may contain deceptive artifacts that influence the agent’s behavior. We call this adversarial task contamination. Whereas prompt injection relies on attacker-supplied instructions, task contamination also includes non-instructional evidence, such as fake results and decoy endpoints. We present AgentLSD, a controlled framework for studying adversarial task contamination. AgentLSD uses Capture the Flag (CTF) challenges as its experimental environment. We inject trap artifacts, such as fake flags, misleading hints, decoy endpoints, and hidden cues, while preserving the intended CTF solution. The framework supports paired clean and trap-augmented experiments with deterministic trap generation, runtime injection, telemetry, and delivery verification. We evaluate six models on 11 web CTF challenges. In the clean condition, agents capture 41% of the flags, and no model solves every challenge. We then measure the impact of task contamination. Even when the agent still recovers the flag, traps increase the number of turns (+20) and reasoning tokens (+2k). Solve-rate effects are more heterogeneous, as some model–challenge pairs are largely unaffected while others follow decoys or submit wrong flags. These results show that clean CTF performance understates vulnerability to deceptive task evidence. AgentLSD isolates this effect and provides a reproducible benchmark for studying it. We release the framework, configurations, trap specifications, and raw traces.
Research paper Calibrating One-Round Membership Inference with Neighbors
Francesco Rita, Jie Zhang, Florian Tramèr
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The state-of-the-art Membership Inference (MI) methods calibrate their signal separately for each example using reference models, auxiliary models trained to exclude the target. This paradigm scales poorly to modern large models, however, whose training is too expensive to replicate. This has motivated one-round settings, where only a single trained model is available; but without reference models the per-example calibration that drives the strongest attacks can no longer be estimated, leaving the membership signal weak. We ask whether neighbors of the target point can recover this calibration without training any additional model. Our key observation is that reference models serve only to reveal how an example behaves under models not trained on it, and that querying the target model on nearby samples yields the same information. We propose two complementary ways to obtain such neighbors, and show that querying them against an early training checkpoint further sharpens the signal. We evaluate across three image classification datasets and three training setups, showing that neighbors yield strong membership signals and competitive attack performance at no additional training cost.
Research paper Compositional Dual-Trigger Backdoors for Independent Prediction and Explanation Manipulation
Mina Mehrvarz1, Stjepan Picek1,2
- 1Radboud University, Nijmegen, Netherlands
- 2University of Zagreb Faculty of Electrical Engineering and Computing, Zagreb, Croatia
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Backdoor attacks traditionally manipulate model predictions, while recent explanation-aware attacks have shown that post-hoc explanations can also be compromised. However, it remains unclear whether prediction and explanation backdoors can coexist as independently activated behaviors within a single model. We introduce a compositional dual-trigger framework in which one trigger manipulates Grad-CAM explanations while preserving predictions, and a second trigger causes targeted misclassification while preserving the previously learned explanation behavior. The two backdoors are embedded sequentially using partial layer freezing and replay-based regularization, enabling independent or simultaneous activation. We evaluate the framework using BadNet-, WaNet-, and Grond-based triggers across five CNN and Vision Transformer architectures on CIFAR-10, CIFAR-100, and Tiny ImageNet. The results show that explanation-aware backdoors extend beyond visible patch triggers and that prediction and explanation manipulation can coexist in most evaluated settings. However, their compatibility depends on the architecture, dataset, and trigger composition. These findings demonstrate that backdoored models may contain multiple independently activated malicious behaviors and highlight the need to evaluate explanation integrity alongside predictive integrity.
Research paper Controlling Autonomous Vehicles using Continuous Adversarial Patches Spotlight
Pia Hanfeld1,2, Erik Imgrund1,2, Felix Weissberg1,2, Thorsten Eisenhofer3, Wolfgang Hönig2, Konrad Rieck1,2
- 1BIFOLD
- 2TU Berlin
- 3CISPA Helmholtz Center for Information Security
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Autonomous vehicles, including self-driving cars and drones, heavily rely on machine learning models for perception and control. This reliance introduces a significant attack surface through adversarial patches—visual patterns that mislead learning models. While prior work has demonstrated that such patches can induce misclassifications or tracking failures, they fall short of enabling sustained control over autonomous systems in rapidly changing conditions.
In this paper, we introduce continuous adversarial patches, a proof-of-concept attack that demonstrates the potential for sustained control over autonomous vehicles that rely on single object tracking. When displayed on a video screen, these patches guide drones along adversary-defined trajectories. We implement a diffusion model to produce continuous adversarial patches in real time, targeting PULP-Frontnet and YOLOv5, two object detection models used in drone research. Our method demonstrates successful trajectory manipulation under controlled conditions, including slingshot and freestyle maneuvers. We release our simulation environment and code to facilitate further investigation of this attack class and the development of robust countermeasures.
Position paper Emergence-Driven Security of LLM Agents
Nektaria Kaloudi1, Georgios Kavallieratos2, Georgios Spathoulas1, Sokratis Katsikas1
- 1Norwegian University of Science and Technology
- 2Aristotle University of Thessaloniki
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Large language model (LLM) agents are no longer limited to text generators, but they can also plan, call tools, delegate tasks to other agents, act within external environments, and change states in response to their actions. In Anthropic's recent report on an AI-orchestrated cyber-espionage campaign involving Claude Code, individual subtasks appeared legitimate when evaluated in isolation but became malicious when combined into an autonomous attack sequence. Consequently, the security of such complex LLM-based agentic systems may fail even when each component appears secure in isolation. This position and open-problem paper argues that LLM agent security should be studied as emergence-driven security: the analysis of security properties that arise from the interactions among agents and its components over time. We define emergence-driven security and provide a conceptual taxonomy to classify emergent security-related phenomena in LLM agents, covering both beneficial and harmful forms of emergence. Based on these insights, we propose EASE, an Emergence-Aware Security Evaluation framework that provides a systematic process for assessing how interactions among agents combine over time to produce harmful or beneficial system-level security outcomes. Finally, we conclude by outlining open problems for studying emergent behavior in LLM agents in the context of security. The paper is intended to provide a foundation for examining how the emerging capabilities and operational needs of LLM agents may shape security evaluations that go beyond static, model-level testing.
Research paper False Prophets: On the Security of World Models in Agentic Systems Spotlight
Erik Imgrund1,2, Anna Wimbauer1,2, Klim Kireev1,2, Konrad Rieck1,2
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Large language models now power autonomous agents capable of complex, multi-step tasks in different environments. Accurate and reliable execution of these tasks requires the agent to predict the results of its actions. Recent research proposes to enhance predictive capabilities via specially trained environment simulators–world models. While world models can improve performance, they can also mislead agents into executing harmful actions, creating significant security and privacy risks. In this paper, we raise security concerns regarding the usage of world models in agentic systems. We discover a range of world model specific vulnerabilities, which can be exploited in terminal-based agents to execute malicious code or extract sensitive data. To facilitate future development, we introduce a security benchmark dataset designed for text-based world models. We argue that some risks are intrinsic to approximate world modeling, and show that attackers can induce mispredictions in agentic pipelines with up to 95 % success rate, possibly resulting in unintended command execution, denial of service, drainage of wallet and private information extraction. Finally, we provide practical recommendations for practitioners to mitigate the discovered harms and harden agentic systems.
Research paper Fooling Local Optimizers: Adversarial Initialization Attacks on LiDAR Localization
Madhurima Ghosh1, Pranav Shetty1, Hyungsub Kim2, Mridula Singh1
- 1CISPA Helmholtz Center for Information Security
- 2Indiana University
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LiDAR (light detection and ranging) localization is a key component of autonomous driving systems, enabling accurate vehicle pose estimation through optimization-based scan registration methods (e.g., the normal distributions transform algorithm). Existing adversarial attacks mainly target the observation space by manipulating LiDAR point clouds, overlooking another important dependency: the position prior used to initialize the optimizer. In this paper, we identify the initialization space as a previously unexplored attack surface and show that GNSS spoofing can drive LiDAR localization to incorrect local optima. Experiments on the Autoware-CARLA platform reveal a convergence basin of approximately 4 m, beyond which initialization perturbations lead to localization failures. Our analysis of observation-space attacks shows that localization errors induced by LiDAR spoofing exhibit a stable magnitude and a dominant drift direction over time. Leveraging these insights, we propose a cross-space adversarial attack that jointly exploits the initialization and observation spaces by coordinating GNSS spoofing with LiDAR manipulation, demonstrating that coordinated perturbations across sensing modalities can propagate through the complete localization stack. The proposed attack increases the mean localization error by approximately 7 m for A-LOAM and 15 m for HDL-Localizer compared to observation-space attacks alone. These findings expose vulnerabilities arising from interactions between initialization and observation spaces and provide a basis for evaluating the security of autonomous vehicle localization systems.
Research paper Ghost Approvals: Approval-Provenance Failure in Agentic AI Frameworks
Yuvraj Pradhan1, Aman Singh1, Archana Kumari1, Abhishek Pradhan2, Deepak Kumar Singh3
- 1MIT ADT University
- 2Independent Researcher
- 3NVIDIA
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Agentic AI systems increasingly execute actions for users, including transfers, deployments, account changes, and data release. Human approval gates are meant to prevent these actions from running until a reviewer has inspected the proposed action and issued a decision. Because approval can arrive after a delay, frameworks often persist workflow state and resume later. The resume path therefore becomes a security boundary: it must distinguish evidence that a human approved from approval-shaped values stored in mutable state. We define Approval-Provenance Failure as a condition in which a workflow resume path treats mutable approval-relevant state as evidence that a trusted human approval path produced a decision. Our adversary can write approval-relevant workflow state, but cannot use the approval path, change the model, modify tool code, invoke the tool directly, write the business database, mint a valid approval artifact, or access the approval issuer key. We evaluate 18 agent frameworks with human approval, interruption, or pause-resume behavior. Thirteen are exposed, three are resistant, and two are non-applicable. In exposed cases, state-only approval forgery causes gated action execution after a negative control blocks ordinary resume. The failure also forges the evidence of human oversight itself: across 500 paired audit traces, genuine and forged records are statistically indistinguishable, with exact-match rate 1.0 and AUC 0.5 under the tested native audit-field projection, while provenance evidence separates them with AUC 1.0. Finally, we evaluate a provenance-bound approval artifact that blocks 13 adversarial variants on five representative targets with microsecond-scale verification cost per resume.
Research paper HideOut - User Protection Against Localization with Throughput Guarantees in Mobile Networks
Navidreza Asadi1, Michele Guardiani1, Wolfgang Kellerer1, Jafar Mohammadi2
- 1Technical University of Munich
- 2Nokia
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Channel state information (CSI) in cellular networks is primarily used to maintain quality of service (QoS), yet it leaks privacy-sensitive information, in particular the user equipment’s (UE) location. CSI is reported in plaintext on a publicly available schedule; thus, capturing it on the air and using a well trained AI model to localize the UE is straightforward. This simplicity in the attack execution makes it a serious privacy vulnerability. Using conventional privacy enhancing techniques, such as additive perturbation from differential privacy, to protect location data can potentially degrade the downlink communication quality. We present HideOut, a client-side defense mechanism that preserves the user’s location from neural-based localization methods, while maintaining their downlink Spectral Efficiency (SE). Unlike generic adversarial attacks, HideOut treats downlink SE as a strict constraint in an optimization setting. Under maximum ratio transmission (MRT) beamforming, we show that a user-selected SE loss budget can be converted into an angular rate-feasible constraint on the reported channel vector. HideOut then performs gradient-based localization obfuscation while projecting each update onto this rate-feasible set. We evaluate HideOut against four CSI-based localization architectures under both white-box and black-box assumptions. Across models, HideOut increases localization ambiguity (error) from approximately 1–2 m to 72–85 m while keeping downlink SE loss within a 1% budget. These results show that CSI-based localization can be substantially degraded at negligible communication quality loss when adversarial perturbations are made aware of the wireless link.
Research paper InferD: A Honeypot Framework for AI Inference Infrastructure
Hicham Hammouchi, Gabriele Lenzini
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Large language model serving stacks, commercial inference APIs, vector databases, and agent orchestration gateways are now ex- posed on the public internet and indexed by commodity scanners within hours of deployment. The threat characteristics of this sur- face are only beginning to be measured, and the honeypot frame- works that could measure it were designed for conventional net- work services rather than for AI infrastructure. In fact, emulating an AI service is a distinct deception problem: the observable behavior of the service, including model inventories, token formats, tool-call protocols, and authorization flows, must be reproduced faithfully, while the underlying computation, model inference and tool ex- ecution, must never occur. We present InferD, a low-interaction honeypot framework organized around a single principle we call deception without inference: every request an adversary can observe is answered from static response pools, and nothing an adversary submits is ever executed. InferD decomposes the emulation into four deception planes, transport, service protocol, vulnerability surface, and agentic session, adds a provenance plane that links a planted credential to evidence of downstream model-mediated processing.
Research paper LEASH: Zero-Trust Containment for AI Agent Swarms
Saurabh Deochake
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Autonomous AI agents increasingly spawn sub-agent swarms that carry derived credentials to APIs, databases, and production infrastructure. When an operator kills a misbehaving orchestrator, its descendants keep exercising valid credentials for minutes to hours, since every deployed revocation mechanism needs network connectivity to a central authority, unavailable precisely when the network is degraded or adversarial. This paper presents LEASH - Liveness-Enforced Authorization for Swarm Hierarchies, which applies the zero-trust principle of continuous verification to a delegation hierarchy without a reachable authority. A parent emits a signed, epoch-indexed liveness beacon every Δh seconds (beacon interval), each child staples a fresh beacon into every authentication proof, and the enforcement point checks freshness using only cached public keys and a local clock. Revocation happens by omission: when beacons stop, all descendants fail closed within a bounded zombie window Wz ≤ Wmax + Δh + ϵ, where Wmax is the maximum beacon age and ϵ is the clock skew. Immediate-parent verification at O(1) and full-chain verification at O(d), where d is the hierarchy depth, extend this bound against compromised intermediates. We evaluate LEASH with real GPT-4o-mini agent swarms: 0.71% tool-call overhead, cascading revocation across a 49-agent four-level hierarchy within bound, and 295× less credential-theft exposure versus OAuth 2.0. Under prompt injection that bypasses application-layer guardrails, LEASH denies every post-revocation tool call, since enforcement sits below the LLM.
Research paper MCP Tool Poisoning in Agentic AI Frameworks: A Cross-Framework Measurement Study
Farooq Shaikh, Biagio Montaruli
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The Model Context Protocol (MCP) enables agentic AI frameworks to connect language models to external tool providers, yet its design carries attacker-controlled content, spanning tool descriptions, schema fields, and response data, directly into model context without validation. Prior benchmarks measure model compliance with poisoned instructions but stop short of confirming real execution, do not isolate the framework layer's contribution to defense, and do not document vendor accountability.
We present the first cross-framework measurement of MCP tool poisoning with real tool execution. A 25-class root-cause taxonomy unifies prior classifications (Invariant Labs, MCPTox, OWASP MCP03, MSB, AgentDojo, ETDI, CSA) across all protocol entry points, and an open-source tool mcpvenom drives a 9,720-cell susceptibility matrix across 12 frameworks, 18 models, and 45 attack scenarios, with a dual oracle that independently confirms exfiltration via canary HTTP receipt.
The overall attack success rate is 22.9% (2,113 vulnerable cells) across three evidence tiers: dispatched attacker tool call (64.9%), confirmed network contact with the attacker endpoint (23.0%), and verified secret exfiltration (12.1%); verdicts were validated by hand across 1,259 transcripts. All observed resistance is model-level: across the tested configurations, nine core frameworks cluster within 23 to 26% (χ² = 3.30, p = 0.91), with no framework implementing intentional defense, though incidental framework properties do provide mitigation in specific cases: duplicate-tool-name rejection in Pydantic AI (16.6% ASR) and executor constraints in AG2 (4.6%); a regex scanner implementing the recommended description checks rejects 20 of the 45 scenarios at a 7.2% false-positive rate on 125 benign descriptions, so metadata scanning alone is a partial control. Model ASR ranges from 0.4% (Claude Fable 5) to 49.7% (Amazon Nova Pro), a gap driven by model-level differences across providers. Claude Opus 4.8 is vulnerable in only 8 of 530 cells (1.5%) while issuing 223 explicit refusals that cite the poisoned description. Claude Sonnet 5 exhibits a narrate-then-comply pattern, verbally identifying the attack as a prompt injection before executing the exfiltration call. Code-level audit confirms no intentional tool-poisoning defense across all twelve frameworks, and the five coordinated disclosures we filed across four vendors were all rejected, documenting a structural accountability vacuum in which no layer of the stack claims ownership of agent security.
Research paper Position Matters: Feature Inversion Attacks in ViT Split Inference with Token Reduction and Shuffling
Stefano Leggio, Giulio Rossolini, Alessandro Biondi
- Scuola Superiore Sant'Anna
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Vision Transformers (ViTs) are increasingly used in split-inference systems, where edge devices transmit intermediate token representations to a remote cloud. In this setting, token reduction lowers computation and communication costs, while token shuffling disrupts the spatial organization of the transmitted tokens, potentially limiting information leakage. However, their privacy benefits remain unclear against feature inversion attacks, which attempt to reconstruct the input from the transmitted embeddings. In this work, we show that, despite disrupting the spatial structure required by conventional reconstruction attacks, transmitted token embeddings retain substantial positional information. Based on this observation, we introduce the Spatially Aligned Reconstruction Attack (SARA), a unified pipeline that predicts token positions, restores their spatial layout, reconstructs missing embeddings using a feature-space masked autoencoder, and recovers the input image. Our results demonstrate that token shuffling provides only apparent privacy, as SARA largely reconstructs the original token organization. Token reduction offers stronger protection, but significant leakage persists when the retained tokens preserve sufficient semantic and positional information. Finally, we introduce a lightweight edge-side defense that removes positional embeddings and progressively adapts the edge-side transformer blocks through knowledge distillation. It substantially reduces attack performance against SARA, while preserving downstream task accuracy and requiring no changes to the cloud-side model.
Research paper PromptLeaks: Assessing Data Leakage in Guardrails and Automated Jailbreak Tools Spotlight
Kobe Sauwens, Simon Knuts, Tim Van Hamme, Lieven Desmet
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Large language models (LLMs) have become ubiquitous, and with their adoption comes a range of ethical and security risks that has made alignment, and resistance to jailbreaking, a central concern. Guardrails are a widely adopted defense against such jailbreaks, yet their reported effectiveness is only as reliable as the data on which they are evaluated. This paper identifies a largely unexamined source of inflated performance: data leakage between the datasets used to seed red-teaming frameworks and those used to train guardrails. As both are derived from a shared corpus of human-authored jailbreak prompts, a guardrail may be evaluated on instances present in its own training data, in which case high detection rates reflect memorization rather than a generalized alignment policy. We quantify this contamination, which we term PromptLeaks, using a deterministic syntactic comparison of prompt datasets adapted from bioinformatics. Across three open-source red-teaming frameworks and five open-source guardrail datasets we observe severe leakage, with one test-prompt dataset almost entirely contained within the guardrail training corpora. Guardrail detection further deteriorates markedly on prompts that do not overlap the training corpus, indicating that current guardrails rely substantially on memorization rather than on generalizing an alignment policy.
Research paper Protecting User Prompts Via Character-Level Differential Privacy
Shashie Dilhara Batan Arachchige, Hassan Jameel Asghar, Benjamin Zi Hao Zhao, Dinusha Vatsalan, Dali Kaafar
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Large Language Models (LLMs) generate responses based on user prompts. Often, these prompts may contain highly sensitive information, including personally identifiable information (PII), which could be exposed to third parties hosting these models. In this work, we propose a new method to sanitize user prompts. Our mechanism uses the randomized response mechanism of differential privacy to randomly and independently perturb each character in a word. The perturbed text is then sent to a remote LLM, which first restores the prompt and then performs the intended downstream task. The idea is that non-sensitive words can often be reconstructed using cues from the context, as well as the fact that these words are often very common. In contrast, perturbation makes sensitive words more difficult to reconstruct because they are rare. Our mechanism belongs to the broader class of prompt-sanitization methods and may still be vulnerable to reconstruction from contextual or auxiliary information. However, it does not require sensitive information in the prompt to be identified in advance. We evaluate our method on the i2b2/UTHealth and Enron datasets using two LLMs and compare it with two word-level differentially private mechanisms and Microsoft Presidio under a unified privacy-utility evaluation. We also consider stronger adversaries, including a more capable LLM and one with auxiliary information. Our results show that sensitive PII is reconstructed at rates close to the theoretical random-word baseline, while non-sensitive words are recovered at much higher rates. We also provide a mechanism for selecting ϵ ϵ values for different reconstruction models to improve the privacy-utility tradeoff.
Benchmark paper Rag n' Roll: A framework to Evaluate Indirect Prompt Manipulation Attacks against RAG-based Applications
Gianluca De Stefano, Lea Schönherr, Giancarlo Pellegrino
- CISPA Helmholtz Center for Information Security
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Retrieval Augmented Generation (RAG) is a technique commonly used to equip LLMs with out-of-distribution knowledge by collecting, indexing, retrieving, and providing to the model specific information useful to answer user questions. The knowledge is often collected from public document repositories, providing a gateway for indirect prompt injections: attackers may craft documents specifically optimized to control the generated answer.
In this paper, we investigate the practical performance of optimization techniques in hijacking the outputs of RAG pipelines. First, we review the frameworks commonly used to build RAG applications, derive a prototypical architecture, and identify critical parameters. We then examine prior work, seeking techniques for performing indirect prompt manipulations. We adopted five techniques across two macro-families and evaluated the criteria used to assess their effectiveness. With this knowledge, we implement Rag n' Roll, a framework to evaluate the end-to-end results of LLM-based pipelines, introducing new metrics to better understand the benign or malicious nature of the generated answers.
Our results show that established evaluation practices are insufficient to precisely assess attacks against RAG-based pipelines, leading to overestimates of their success. Furthermore, while attacks can successfully control up to 70% of the generated answers, we show that these performances depend heavily on previously ignored pipeline parameters.
Finally, we distill our findings into actionable tips for developers looking to harden their RAG pipelines.
Research paper Repeat-After-Me: Black-Box Adaptive Visual Prompt Injection
Sizhe Chen1, Yu-Lin Tsai1, Ivan Evtimov2, Kamalika Chaudhuri2, Raluca Popa1, David Wagner1, Arman Zharmagambetov2
- 1University of California, Berkeley
- 2Meta
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Prompt injection is widely recognized as a major security threat to AI agents that interact with untrusted external data, such as websites, documents, and emails. Prior work has shown that, in the text domain, black-box prompt injection can achieve near-perfect attack success rates (ASRs). In the image domain, however, existing visual prompt injection methods are substantially less effective in attacking frontier commercial VLMs for materially harmful behavior. Achieving such outputs is hard because it requires a long and/or format-compliant target string, such as a precise, parseable native tool call with exact function names and arguments.
We present Repeat-After-Me, a black-box adaptive visual prompt injection attack that can reveal personally identifiable information or make malicious tool calls. Across both open-weight and commercial frontier VLMs, including Qwen3.6-27B and GPT-5.5, our method achieves ASRs exceeding 82% and 47%, respectively, under a realistic setting in which the benign user prompt is semantically unrelated to the injected task and does not verbally authorize it. Our optimized injection has non-trivial attack transferability across commercial VLMs and benign samples. We show our attack works in cases where adaptive textual prompt injection fails. In a real-world OpenClaw agent connected to Discord, an untrusted user can use a minimally injected image from our attack to overwrite TOOLS.md, enabling future sensitive behaviors like remote code execution and secret exfiltration. We discuss potential defenses.
Research paper SecAgg++: A Post-Quantum Privacy Perserving Federated Learning Protocol
Alessandro Perez1, Giulia Cavicchioni1, Silvio Cretti1, Riccardo Longo1, Alessandro Tomasi1, Silvio Ranise2,1
- 1Fondazione Bruno Kessler
- 2University of Trento
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Secure aggregation is a fundamental building block for privacy-preserving federated learning, yet most existing masking-based secure aggregation protocols do not provide post-quantum security. In this work, we present SecAgg++, a masking-based post-quantum secure aggregation protocol for the single-server setting. SecAgg++ integrates post-quantum cryptographic primitives while preserving the communication and computational efficiency of classical frameworks such as SecAgg and SecAgg+, and supports client dropout handling through an efficient recovery procedure.
Research paper Semi-Automated Detection of Gaps in LLM Security Knowledge
Shufan Chai, Liangliang Sun, Jessica Staddon
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Large language models (LLMs) are increasingly used for a range of software, hardware and human-centered security tasks. Consequently, LLM performance on security tasks is an active area of measurement and research, often with a focus on identifying areas in which LLM security “knowledge” may be insufficient. Popular strategies for identifying LLM security knowledge gaps include building corpora of challenge questions or task benchmarks, strategies that require substantial manual work and security expertise to design and execute. We introduce a partially-automated method for assessing LLM knowledge of a security area. The method uses authoritative information from Consumer Protection Agencies (CPAs) to identify instability in LLM responses that can be indicative of knowledge gaps. We demonstrate the method for 2 security topics, identity theft and impostor scams, and 5 LLMs in 2 leading LLM families, Gemini and GPT, using publicly available information about identity theft and impostor scams from 6 CPAs. The method distinguishes between models that have and don’t have sufficient knowledge to accurately identify the security topics in text narratives.
Research paper SENTRA: Privacy-Preserving Training in Outsourced Cloud Environments
Maryam Zarezadeh1, Jana Eisoldt1, Bhavish Mohee2, Stefan Köpsell1, Behzad Abdolmaleki2
- 1Barkhausen Institut
- 2University of Sheffield
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Training machine learning models in untrusted clouds requires strong guarantees of confidentiality, integrity, and correctness, while remaining scalable and resilient to node churn. These challenges are further amplified in emerging agentic AI systems, where autonomous and distributed learning components require trustworthy coordination and secure state management across heterogeneous cloud environments. Existing Trusted Execution Environments (TEEs) lack scalability and remain vulnerable to side-channel attacks for large workloads, while pure secure multi-party computation (MPC) approaches incur prohibitive overhead in practice. SENTRA (Secure ENclave-based TRaining Architecture) addresses these challenges through a hybrid architecture that combines TEEs, secret sharing, and communication-efficient MPC with system-level mechanisms that secure the entire training lifecycle. SENTRA introduces a scalable collective attestation protocol that verifies all participating enclaves and enforces hardware exclusivity before any node may store or process secret shares. Training data and model parameters are stored as secret shares in a versioned enclave-backed key–value store (KVS), providing rollback resistance and consistent state under the stated threat model. SENTRA further supports dynamic, fault-tolerant membership management, rollback resistance, and recovery from node failures. Evaluation of a prototype implementation shows that SENTRA achieves up to 8.89 samples/s throughput in software-only mode. In hardware-enclave mode, SENTRA provides memory-isolated confidentiality, fault-tolerant membership management, rollback resistance under the stated threat model, and recovery from node failures in approximately 8 seconds.
Research paper TERMon: Detecting Persistent Behavioral Threats in Edge AI via Hardware-Native Ternary Runtime Monitor
Arish Sateesan, Edlira Dushku
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Edge AI accelerators are increasingly deployed in safety-critical environments, where model outputs may control physical actuators, make access-control decisions, or trigger alarms. In these settings, runtime failures often remain undetected because model corruption, distribution shift, and adversarial inputs can still produce well-formed, confident predictions. This paper presents TERMon, a lightweight hardware runtime monitor that detects such anomalies by observing inference behavior rather than re-executing or formally verifying the model. TERMon represents class-conditional trusted behavior as hardware-efficient ternary patterns that are matched in parallel against a thermometer-encoded fingerprint. The ternary encoding reproduces the corresponding unquantized range decision exactly. TERMon detects harmful weight corruptions in proportion to their behavioral impact, while out-of-distribution and adversarial inputs are largely not separable using the monitored features at a strict false-positive operating point. We implemented TERMon on a PYNQ-Z2 FPGA, and the pipelined design requires no on-chip block RAM or DSPs and has a two-cycle decision latency.
Position paper Towards a General Framework for AI Forensics
Wei Herng Choong, Daniel Kowatsch, Bettina Zieger, Maximilian Wendlinger, Pascal Debus
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As artificial intelligence (AI) is deployed in safety- and security-critical domains, AI systems have become attractive targets for attacks that exploit their learning mechanisms, dependence on training data, and sensitivity to input perturbations. Such attacks create a need for methods and protocols to analyze, detect, and prove their occurrence, both for organizations improving defenses after incidents and for law enforcement agencies proving criminal offenses in court. AI forensics addresses this need by adapting forensic principles to AI systems. The development of AI forensics tools and measures remains at an early stage. Existing work mainly proposes isolated methods for specific attacks rather than structured approaches for reasoning about forensic measures. Moreover, forensic techniques are not systematically distinguished from reactive defenses, and uniform guidelines for producing comparable and admissible forensic findings are lacking. In this paper, we analyze the relationship between AI forensics and AI defenses and identify limitations in current descriptions of attack scenarios and forensic measures. Based on this analysis, we propose guidelines for the systematic analysis of attack scenarios and for the development as well as documentation of forensic measures. These guidelines enable clearer definitions of the hypotheses tested by individual forensic measures and help situate each measure within a plausible attack scenario and in relation to other measures that test related hypotheses. We demonstrate the applicability of our guidelines through a case study, thereby contributing to the development of AI forensics as a structured and legally defensible discipline.
Benchmark paper Trojan Hippo Bench: A Dynamic Benchmark for Persistent Memory Attacks and Defenses in LLM Agents Plugins Spotlight
Debeshee Das1, Julien Piet2, Darya Kaviani2, Luca Beurer-Kellner3, Florian Tramèr1, David Wagner2
- 1ETH Zurich
- 2University of California, Berkeley
- 3Snyk
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Memory systems enable otherwise-stateless LLM agents to persist user information across sessions, but also introduce a new attack surface. The Trojan Hippo attack is a class of persistent memory attacks that operates under a more realistic threat model than prior memory poisoning work. The attacker plants a dormant payload into an agent's long-term memory via a single untrusted tool call (e.g., a crafted email), which activates only when the user later discusses sensitive topics such as finance, health, or identity, and exfiltrates high-value personal data to the attacker. While anecdotal demonstrations of such attacks have appeared against deployed systems, no prior work systematically evaluates them across heterogeneous memory architectures and defenses.
We introduce Trojan Hippo Bench, a dynamic evaluation framework for persistent memory attacks and memory-layer defenses, comprising two components: (1) an OpenEvolve-based adaptive red-teaming benchmark that stress-tests defenses and memory backends against continuously refined attacks, and (2) a capability-aware security/utility analysis for persistent memory systems, enabling principled reasoning about defense deployment across different usage profiles. Instantiated on an email assistant across four memory backends (explicit tool memory, agentic memory, RAG, and sliding-window context), the undefended Trojan Hippo attack achieves up to 85–100% attack success rate (ASR) against current frontier models from OpenAI and Google, with planted memories successfully activating even after 100 benign sessions. We evaluate four memory-system defenses inspired by basic security principles; they reduce attack success to as low as 0–5%, but at utility costs that vary widely with the task mix. Effective real-world deployment thus remains an open challenge that Trojan Hippo Bench is built to study; we release it to support reuse and extension.
Benchmark paper What Breaks Local Watermarks? A Robustness Benchmark for Local Invisible Image Watermarking
Kai Yao1, Bence Szilágyi2, Sebestyén Kamp2,1, Máté Poór2, Máté Szilveszter2, Matyas K. Zsoldos2, Marc Juarez1
- 1University of Edinburgh
- 2Garandor
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Local image watermarking embeds an invisible signal into selected image regions rather than spreading it across the entire image, enabling payload recovery from specific objects or regions without perceptibly altering the image. Existing studies evaluate the robustness of payload recovery and localization under image transformations, but they often focus on their own proposed method, resulting in narrow evaluations with inconsistent choices of transformations, datasets, and metrics. These inconsistencies across studies limit direct comparisons across methods and muddle the overall picture of local watermark robustness. To address this gap, we present the first systematic robustness benchmark for local watermarks across 55 image transformations, including (i) signal distortions, (ii) changes in image coordinate alignment, (iii) indirect local edits, and (iv) direct watermark edits. The benchmark evaluates MaskWM, WAM, OmniGuard, TrustMark, and PixelSeal, all methods that either provide native localization or require minimal adaptation to support it. Our results show that all evaluated methods are vulnerable to some transformation, with MaskWM standing out as offering the strongest payload recovery and localization, although it has the lowest image quality in the clean setting. Synchronization further improves MaskWM's payload recovery under several geometric transformations, albeit at an additional cost to image quality. A key finding is that local watermark robustness depends strongly on the nature of the transformation: signal distortions are often tolerated by the strongest methods, while geometric misalignment and generative local edits, such as inpainting and outpainting, can completely impair payload recovery. We observe that payload recovery and localization are related but not interchangeable, and both strongly depend on the transformation's impact on the watermark region.