48 results for “server”

PrivacyTrace is a benchmark of 1,000 synthetic user profiles and 4,000 agent trajectories across four domains, built with real tools from 25 MCP servers. Four LLM attackers inferred user attributes from tool-call traces alone at a 26.25% success rate, against 17.97% for prior-based guessing. Tool arguments and returned results gave the main evidence, and linking traces across sessions raised the risk.

arxiv.orgpaperAdded 3 Nov 2026, published 30 Oct 2026🛡️ Security

PrivacyTrace is a benchmark from the Shanghai AI Laboratory (AgentDoG Team, October 2026) that tests how much a passive observer can infer about a user from MCP tool-call traces alone. It has 1,000 synthetic profiles, 4,000 trajectories and 67,950 calls across 25 MCP servers. Four LLM attackers reached 26.25% attribute accuracy against a 17.97% prior baseline, and tool arguments leaked most.

arxiv.orgpaperAdded 3 Nov 2026, published 30 Oct 2026🧠 AI

Cryptanalysis of VTBSAE, a verifier-based PAKE protocol for the Industrial Internet of Things, showing it fails to resist client impersonation after server compromise. The authors propose E-VTBSAEv1, which binds the client point E1 to fresh server randomness, and prove AKE security and forward secrecy in the random-oracle model under CDH. Raspberry Pi 4B tests show runtime comparable to VTBSAE with the same communication and storage overhead.

eprint.iacr.orgpaperAdded 31 Oct 2026, published 29 Oct 2026🛡️ Security

CRISP is a combination-aware framework that co-designs pruning and runtime scheduling for Mixture-of-Experts inference on memory-constrained edge platforms. It reorders neurons by importance so one stored expert supports several execution widths, gives hot, warm and cold expert combinations different widths, and overlaps expert loading with computation. On Mixtral-8x7B and DeepSeek-MoE-16B it raises throughput up to 2.1x at the same memory budget, with accuracy loss limited to 3.6%.

arxiv.orgpaperAdded 28 Oct 2026, published 27 Oct 2026🧠 AI

AlgOssa is a decentralized secure aggregation protocol built on Ossa, a generic committee-aided, single-server construction for one-shot clients (following OPA and Willow, CRYPTO 2025). Ossa realizes secure aggregation with non-selective abort against a malicious server. AlgOssa adds Algorand-style sortition to rotate leaders and committees, bounds the chance of an honest server, and gives eventual delivery. Classical and post-quantum routes are evaluated.

eprint.iacr.orgpaperAdded 28 Oct 2026, published 27 Oct 2026🛡️ Security

Measurement study of 23,102 third-party Discord bots and 183,142 user reviews (2021-2026, 49 languages). A fine-tuned DeBERTa classifier plus manual validation yields 8,832 security and privacy reviews, mapped to a 31-theme taxonomy; Data Sharing (30.5%) and Data Collection (16.2%) dominate. Permission count and admin status correlate only weakly with user concerns. The authors build BotLens, an MCP-server auditing framework with six tools.

arxiv.orgpaperAdded 28 Oct 2026, published 27 Oct 2026🛡️ Security

Log-To-Leak is a prompt-injection attack on tool-using LLM agents that abuses Model Context Protocol tool metadata to trigger an attacker-controlled logging call after the last legitimate call, leaking the user query, server name, server response and agent response. Evaluated on five MCP servers and four agents, it reaches 62.64-100% attack success with 76.55-95.64% logging accuracy. Three defenses leave over 55% residual ASR on GitHub MCP with GPT-4o.

arxiv.orgpaperAdded 28 Oct 2026, published 26 Oct 2026🛡️ Security

LINE-Break is a security analysis of Letter Sealing v2, the custom end-to-end encryption protocol in the LINE messenger. A TLS man-in-the-middle attacker or malicious server can replay, reorder and block messages undetected, and colluding users can forge message authorship in one-to-one and group chats. Stickers and URL previews leak plaintext. The attacks were verified on the real iOS app and an independent implementation.

eprint.iacr.orgpaperPublished and added 26 Oct 2026🛡️ Security

SynTrace is a single-round compiler that adds accountability to linear private information retrieval (PIR). The client mixes the retrieval query with m audit queries, so audit syndromes identify up to d deviating servers among t colluding ones before reconstruction. The paper proves perfect query privacy and zero false identification within the threshold. For Shamir-based PIR it needs k=t+d+1 servers. For a 32 KiB record from a 1 GiB database it uses 2.25 MiB, against 8.96 MiB for the Eriguchi, Kurosawa and Nuida (TCC 2022) homomorphic-MAC construction.

eprint.iacr.orgpaperPublished and added 26 Oct 2026🛡️ Security

DISCO is a distributed, fully oblivious database system that combines hardware enclaves (TEEs) with oblivious primitives to hide access patterns from side-channel and leakage-abuse attacks. New distributed frameworks and communication optimizations let it run in parallel across servers. It reports 88x speedup over Jodes and 180x over SODA on non-foreign-key joins with 2^25 elements, and the first terabyte-scale results.

eprint.iacr.orgpaperAdded 21 Oct 2026, published 20 Oct 2026🛡️ Security

HERMES is a privacy-preserving inference (PI) system optimised for multi-token LLM decoding rather than prefill. It swaps high-round nonlinear protocols for compute- and bandwidth-heavy ones with fewer rounds, and adds a homomorphic-encryption matrix-multiplication protocol that keeps the KV cache encrypted on the server and uses grouped-query attention. On Llama 3.1 8B Instruct it cuts TPOT by up to 2.7× and total PI latency by up to 2.1×.

eprint.iacr.orgpaperAdded 19 Oct 2026, published 18 Oct 2026🧠 AI

ToFu is a tool-aware fuzzing framework for LLM tools, including MCP servers. It maps each tool argument, using its metadata, to one of 74 CWE-guided semantics-aware sanitizers (path, URL, SQL and similar). It then generates schema-valid Atheris harnesses and semantic oracles, using runtime tracers for in-process tools and outcome oracles for opaque ones. The LLM (gpt-4.1) only maps sanitizers and writes seeds; it is never the security judge. The paper also shows a "Repeat-After-Me" trick, where an LLM told to repeat attacker-crafted text emits a tool call the orchestrator executes, reproduced on LangGraph, MAF, ADK 2.0, AutoGen, Strands and CrewAI. Across 273 runnable MCP servers (3,405 tools) it reports 253 verified bugs in 343 tools across 118 servers, such as path traversal, log injection and exfiltration. These are failures a crash-based fuzzer would miss. The result matters because it shows LLM-generated tool arguments cannot be treated as trusted.

arxiv.orgpaperAdded 18 Oct 2026🧠 AI

ToFu is a tool-aware fuzzing framework that derives semantic security checks for LLM tools (mainly MCP servers) from their metadata and a corpus of 74 CWE-guided sanitizers. It generates schema-valid Atheris harnesses, uses runtime tracers and outcome oracles to catch bugs that don't crash, and uses an LLM only to map sanitizers and seed inputs, never as the judge. It also describes a "Repeat-After-Me" attack, in which the LLM is told to repeat attacker-written text that the orchestrator then dispatches as a tool call. It was reproduced on LangGraph, MAF, ADK, AutoGen, Strands and CrewAI. On 273 MCP servers it reports 253 verified bugs across 343 tools in 118 repositories, including path traversal, log injection, exfiltration and command bypass.

arxiv.orgpaperAdded 18 Oct 2026🛡️ Security

FedRAPP is a personalized aggregation framework for Source-Free Federated Test-Time Prompt Tuning (SF-FTTPT), where clients adapt CLIP soft prompts on unlabeled, non-IID test streams without source data. It combines reliability-aware client assessment, a server-side exponential moving-average prompt memory and similarity-guided peer aggregation. Across nine CLIP benchmark datasets and ImageNet variants it beats standard federated aggregation baselines while keeping prompt-only efficiency.

arxiv.orgpaperAdded 20 Oct 2026, published 16 Oct 2026🧠 AI

The paper proposes a traceable and aggregatable tagged witness signature (TA-TWS) and builds SwiftAuth on it, a conditional privacy-preserving anonymous authentication framework for UAVs and other dynamic terminals. Issuers can create authorization components while users are offline. Several credentials compress into one constant-size proof, verifiers can batch-verify across users, and a regulatory trapdoor lets authorities trace misbehaving users. TA-TWS is proven unforgeable and witness-hiding, and benchmarks with the MIRACL Core library on constrained devices and Aliyun servers show it is practical.

eprint.iacr.orgpaperAdded 17 Oct 2026, published 16 Oct 2026🛡️ Security

DK-VLM adds Dual-Kernel Attention to a vision-language model. A semantic kernel keeps the pretrained attention and positional encoding. A separate geometric kernel uses estimated 3D points and camera poses to modulate attention through point displacements and relative view transformations, and a learned gate fuses the two outputs. Geometry therefore enters attention as position, not as fused 3D reconstruction features. The paper also adds Reference-Frame Composition (RC) supervision, which gives stepwise turn and heading targets derived from verified single-step annotations, to train multi-step spatial reasoning as the observer moves. DK-VLM-8B reports the highest average score across six spatial benchmarks among the compared methods, with 74.33 on VSI-Bench and 58.28 on ReVSI-32, and it preserves general video understanding.

arxiv.orgpaperAdded 17 Oct 2026, published 15 Oct 2026🧠 AI

Studies "filesystem capability laundering" in MCP servers: client approval of a tool call grants the server process broad host filesystem access, so attacker-steered arguments can reach sensitive files outside the tool's declared contract. The authors build MCP-FSD, which infers per-tool least-privilege boundaries, plants credential fixtures outside them, and tests exploitability and sandbox containment by paired dynamic execution. Of 21,097 servers from nine registries, 16.4% of 4,806 triaged servers have filesystem capabilities despite non-filesystem classifications. Dynamic validation confirmed 150 vulnerable instances, and disclosure produced 13 advisories, including two CVEs in Anthropic's Git MCP Server.

arxiv.orgpaperAdded 17 Oct 2026, published 15 Oct 2026🛡️ Security

Proposes EdgeFlow, a hybrid KV cache migration scheme for distributed LLM inference across heterogeneous edge servers in Collaborative Edge Computing. It combines direct KV cache transmission with activation-based recomputation, overlapping computation and communication to cut migration time when servers disconnect or overload. The authors formulate a multi-node KV migration optimization problem and give a 2-approximation algorithm built on improved LP relaxation and bipartite graph techniques. Experiments on a real distributed LLM inference platform show up to 45% lower migration time.

arxiv.orgpaperAdded 17 Oct 2026, published 15 Oct 2026🧠 AI

SecAgg++ is a masking-based secure aggregation protocol for single-server federated learning that swaps in post-quantum cryptographic primitives. It keeps the communication and computation efficiency of SecAgg and SecAgg+ and handles client dropout through an efficient recovery procedure built on secret sharing and additive masking. It matters because existing masking-based aggregation protocols are not post-quantum secure, so client model updates would be exposed to quantum-capable adversaries.

eprint.iacr.orgpaperPublished and added 15 Oct 2026🛡️ Security

SecAgg++ is a masking-based secure aggregation protocol for single-server federated learning that uses post-quantum cryptographic primitives. It keeps the communication and computation efficiency of SecAgg and SecAgg+ and handles client dropout through an efficient recovery procedure. It matters because most masking-based secure aggregation protocols are not post-quantum secure, which leaves federated model updates exposed to future quantum adversaries.

eprint.iacr.orgpaperPublished and added 15 Oct 2026🧠 AI

Cryptography paper that extends Chen and Fischlin's two-user Signal analysis (Eurocrypt 2024) to group chats. It introduces "causal awareness": a receiver can reconstruct part of the causal context in which an accepted message was sent. Network delay or adversarial interference can otherwise show an authentic message in a misleading context. Senders transmit records of what they have sent and received, and receivers verify these records and compare them with their own. The paper gives correctness and security definitions parameterized by how much causal information must be recovered, baseline constructions with proofs, and checkpoint-aided and server-aided variants. It also discusses how to surface this information in a messenger's UI.

eprint.iacr.orgpaperAdded 14 Oct 2026, published 13 Oct 2026🛡️ Security

Endor Labs' 2025 State of Dependency Management report examines how AI coding agents and MCP servers add supply chain risk. Researchers analysed 10,663 GitHub MCP server repositories and tested AI-generated dependency recommendations across PyPI, npm, Maven and NuGet, finding agents import vulnerable or non-existent packages. MCP servers are immature: 75% are built by individuals, 41% lack license info, and 82% use sensitive APIs. The report advises treating AI-generated code as untrusted third-party input subject to code review, SAST/SCA and dependency governance.

endorlabs.compaperPublished and added 12 Oct 2026🛡️ Security

TokenRouter is a serving system for token-level routed LLM inference, where different tokens of one request are routed across different models. It uses request-centric programming with model-centric execution: developers write routing logic per request while the runtime launches a subserver per LLM and dispatches requests asynchronously. Each subserver uses a delayed-batching scheduler whose hyperparameters come from a mathematical throughput model, fixing step desynchronization and batch admission delays and giving 2.01-64.15x higher decoding throughput than existing systems.

huggingface.copaperAdded 9 Oct 2026🧠 AI

Presents Reverse-Bleichenbacher, a variant of the Bleichenbacher RSA PKCS#1 v1.5 padding-oracle attack that recovers the least significant bytes first and stops once the TLS PreMasterSecret is found. With improved trimmers and coverage-optimized search, median oracle queries against a 2048-bit key drop from 11,428 to 1,801, and 68.3% of runs finish within a 30s timeout under single-server conditions. The authors find 640 vulnerable domains in the Tranco Top 1M (many behind Alibaba Cloud load balancers) and demonstrate MITM malicious update injection leading to remote code execution.

eprint.iacr.orgpaperAdded 11 Oct 2026, published 8 Oct 2026🛡️ Security

Evaluates delivering security requirements from a governed security-by-design knowledge base (SbD-ToE) to a code-generating LLM through an MCP server at generation time. On DualGauge (59 Python tasks) the share passing all security tests rose from 44.1% to 78.0%; on BaxBench (28 backend scenarios) the share of functionally correct solutions with no successful exploit rose from 65% to 86%, matching the authors' Oracle Security Reminder (85%). The joint secure-and-functional metric did not improve significantly, since stricter code failed functional tests that fix unstated values. The study used one model and one generation per task, and it proposes measuring conformance with applicable requirements rather than only detecting known weaknesses.

arxiv.orgpaperAdded 9 Oct 2026, published 7 Oct 2026🛡️ Security

The preprint tests whether security requirements from a governed security-by-design knowledge base (SbD-ToE), delivered to a code generator through a Model Context Protocol server at generation time, make AI-written code more secure. On DualGauge (59 Python tasks, LLM-judge scoring) the share of tasks passing all security tests rose from 44.1% to 78.0%. On BaxBench (28 backend scenarios with real exploits in containers) the share of functionally correct solutions with no successful exploit rose from 65% to 86%, comparable to the authors' Oracle Security Reminder (85%). The pre-specified joint secure-and-functional metric did not improve significantly, and the stricter code failed functional tests that fix values the task never states. The study used one model and one generation per task. The authors argue that current benchmarks only detect the weaknesses their evaluators were built for, and propose measuring conformance with the requirements that apply.

arxiv.orgpaperAdded 9 Oct 2026, published 7 Oct 2026🧠 AI

PQ-DVSA is a verifiable secure aggregation protocol for federated learning that aims to be post-quantum secure, tolerate client dropouts, let clients verify a server's aggregation result, and resist bounded collusion between the server and clients, while also protecting the aggregation weights, not just model updates. The authors report learning performance comparable to exact weighted aggregation and up to 96 percent lower per-client encrypted-submission runtime than SWAS, the closest prior scheme.

eprint.iacr.orgpaperAdded 8 Oct 2026, published 7 Oct 2026🛡️ Security

PQ-DVSA is a verifiable secure aggregation protocol for federated learning that combines post-quantum cryptography, resilience to client dropouts, and verifiability of the server's aggregation result under bounded server-client collusion. It protects both clients' local model updates and their aggregation weights, lets the server reconstruct the aggregate mask for the active client set after dropouts, and lets clients cryptographically check the aggregation result. Experiments show learning accuracy comparable to exact weighted aggregation while cutting per-client encrypted-submission runtime by up to 96% versus SWAS, the closest prior scheme.

eprint.iacr.orgpaperAdded 8 Oct 2026, published 7 Oct 2026🧠 AI

EntroPrefill proposes a Renyi-entropy-guided mechanism for pruning context mid-prefill in retrieval-augmented generation, using sink-isolated regularized head pooling compatible with grouped-query attention to decide which tokens can be safely discarded. It derives a mixture-to-head deletion envelope bounding feasible token removal, a finite-sample observer guarantee valid under adaptive layer selection, and a conditional transformer perturbation bound with explicit Lipschitz constants and a first-token decision-margin corollary, plus a systems-level break-even analysis of KV-transfer payload versus pruning savings. The paper is explicitly theoretical, defining assumptions and formal limits without reporting empirical speedup or accuracy-preservation results.

arxiv.orgpaperAdded 8 Oct 2026, published 7 Oct 2026🧠 AI

An IACR ePrint paper benchmarks whether running the classical and post-quantum components of hybrid TLS 1.3 key exchange (ECDHE–ML-KEM) and Composite ML-DSA signatures in parallel on separate pthread worker threads reduces handshake latency versus sequential execution. Across three RFC 10024 ECDHE–ML-KEM groups with server and mutual authentication, parallelism sped up all six tested conditions on a standard ARM and x86 system (1.04×–1.28×), with the largest gains in signature stages where component times are balanced, but slowed every condition on a low-power x86 system (0.80×–0.92×) because thread wake/wait overhead outweighed savings. The authors conclude that component independence alone doesn't guarantee a speedup and that parallelization decisions must be validated per target environment.

eprint.iacr.orgpaperAdded 8 Oct 2026, published 5 Oct 2026🛡️ Security

COPEX (COntext Provider EXploitation) is a benchmark that isolates the tool-selecting LLM as the unit of evaluation in Model Context Protocol systems, fixing the surrounding agent stack and varying only the model to measure its intrinsic susceptibility to adversarial context. It covers 25 attack types across 125 scenarios spanning four entry surfaces — model/agent, client, server/tool, and transport — and tests nine models across 3,375 trials, finding a mean attack success rate of 64.4% (58.3%–71.4% by surface); combined input and context scanning cut mean attack success by 49.6% on an eight-attack defense subset. The work separates "system exposure" (attacks succeeding outside the model's observation/control) from "model susceptibility," and the benchmark itself is released publicly.

arxiv.orgpaperAdded 6 Oct 2026, published 3 Oct 2026🛡️ Security

LLMLeak is an attack that abuses an LLM agent's legitimate web-fetching tool as a covert exfiltration channel for malware that cannot itself reach the internet. A local malicious component embeds a secret in a URL disguised as useful reference material (e.g. for a library migration task); when the LLM fetches it, the secret reaches an attacker-controlled DNS or web server, achieving a 79.7% attack success rate across eleven open-parameter models and working against real-world chatbots.

arxiv.orgpaperAdded 2 Oct 2026, published 1 Oct 2026🛡️ Security

Introduces skilder, a framework that enforces access control over enterprise tool access for LLM agents by packaging tools, instructions and limits into roles delivered progressively through a single MCP server, so an agent only ever receives tools it has explicitly learned/unlocked. The paper argues prompt-based policy is merely probabilistic advice, not a hard constraint, and evaluates skilder against flat-context tool selection and multi-agent orchestration across 13 tasks and six models, showing zero unauthorized tool calls or parameter violations (e.g., spending-limit breaches) once agents completed discovery.

arxiv.orgpaperAdded 26 Sep 2026🛡️ Security

Introduces "skilder," a framework that bundles LLM agent capabilities into roles (skills, tools, instructions, and limits) delivered progressively through a single MCP server, so an agent starts with a minimal catalog and only gains tool access as it learns the roles a task requires. This structural approach enforces access control deterministically at the server layer rather than relying on prompt-based policy, addressing context bloat and governance gaps in enterprise tool-using agents. Evaluated against flat-context tool selection and multi-agent orchestration across 13 tasks and six models, showing zero unauthorized tool calls or parameter violations when agents completed the discovery protocol.

arxiv.orgpaperAdded 26 Sep 2026🧠 AI

This preregistered study audits whether black-box LLM judges give stable, reproducible readings on shared serving endpoints, running two campaigns across 52,988 request attempts. Same-window repeat rankings only reached Spearman 0.400 against a required 0.90, and byte-identical next-day replays agreed at 0.78 against a required 0.99, showing that a model name on a shared endpoint is not a frozen measurement instrument. The authors trace the failure to label-to-meaning mapping bias, tiny candidate gaps relative to instrument noise, and non-deterministic outputs on identical inputs, and propose a three-level snapshot-identity ladder plus design rules and a reporting checklist for anyone freezing eval gates on LLM judges.

arxiv.orgpaperAdded 26 Sep 2026🧠 AI

This paper proposes no-box vulnerability analysis, a new paradigm for auditing systems using only functionality metadata when neither system access nor runtime interaction is available. The authors build MCPSEC, a prototype that audits Model Context Protocol servers for indirect prompt injection vulnerabilities purely from tool metadata exposed at server registration, evaluating it against 20 widely-deployed MCP servers with 177 tools where human evaluators confirmed 95 vulnerable tools; MCPSEC achieved 98.9% recall versus 84.2% for an LLM baseline, also producing hypothesized exploitation techniques per finding.

arxiv.orgpaperAdded 26 Sep 2026🛡️ Security

ShareLock is a novel Tool Poisoning Attack against the Model Context Protocol that uses Shamir's secret-sharing scheme to split a malicious instruction into benign-looking fragments distributed across multiple tool descriptions, evading detectors that look for monolithic malicious text in a single tool. A covert trigger planted during a server update reconstructs the hidden instruction, and the authors report over 90% attack success across mainstream LLMs and two MCP clients while evading tool-description-based detection far better than prior single-tool poisoning approaches.

arxiv.orgpaperAdded 26 Sep 2026🛡️ Security

The first large-scale measurement study of authentication security across real-world remote MCP servers, scanning 7,973 live deployments and finding 40.55% expose tools with no authentication at all. For the 119 testable OAuth-enabled servers, the authors built a semi-automated (passive traffic inspection + active dynamic probing) detection framework and derived a taxonomy of nine flaw types across four categories — three MCP-specific (open client environments, dynamic client registration, delegated authorization) and conventional OAuth misconfigurations — finding every tested server had at least one flaw, with dynamic client registration flaws hitting 96.6% of servers and leading to information leakage or account takeover; the work resulted in 9 CVEs via responsible disclosure.

arxiv.orgpaperAdded 26 Sep 2026🛡️ Security

MCPTox is a benchmark for evaluating Tool Poisoning Attacks against LLM agents using the Model Context Protocol, where malicious instructions are hidden in a tool's metadata rather than its output. Built on 45 live real-world MCP servers and 353 authentic tools, it generates 1312 malicious test cases across 10 risk categories via three attack templates, and finds widespread vulnerability across 20 LLM agents: o1-mini has a 72.8% attack success rate, more capable models are often more susceptible due to stronger instruction-following, and even the best model (Claude-3.7-Sonnet) refuses less than 3% of attacks.

arxiv.orgpaperAdded 26 Sep 2026🛡️ Security

A2M (Attraction-to-Manipulation) is a two-stage black-box framework for hijacking agents that use the Model Context Protocol to select tools from third-party MCP servers. The Attraction phase optimizes attacker-controlled tool metadata to raise invocation probability, while the Manipulation phase uses execution traces to craft adversarial tool outputs that steer agent behavior; on LiveMCPBench it achieves a 93.6% malicious tool invocation rate against GLM-4.6, inflates token cost 32.4x under a cognitive denial-of-service variant, and reaches a 74.4% mean attack success rate across information exfiltration, environment integrity compromise, and reasoning derailment, with partial transfer (63.6%/2.7x/24.5%) to four other models without re-optimization. The authors argue this exposes a semantic supply-chain risk in MCP tool ecosystems and call for stronger tool vetting and runtime isolation.

arxiv.orgpaperAdded 2 Oct 2026, published 22 Sep 2026🛡️ Security

This paper analyzes authentication/authorization gaps in the six official Model Context Protocol SDKs (Python, TypeScript, Go, Rust, C#, Swift), identifying structural shortcomings for enterprise zero-trust deployments: single-header credential binding that breaks dual-persona (human SSO vs. service-account) setups, no pre-authentication tool discovery, and no fine-grained per-tool authorization. The authors propose composable FastMCP extensions — cross-header credential normalization, cached cross-IdP token verification, an unauthenticated metadata/discovery endpoint, and permission-filtered tool visibility enforced consistently at invocation — and test them against four frontier LLMs over 2160 attempts, showing an in-body-check-only server leaks forbidden tools 21.1% of the time versus 0% with permission-aware visibility, while also showing visibility-only filtering is still bypassable by scripted clients and models can infer hidden tool names up to 94% of the time from prompt context.

arxiv.orgpaperAdded 2 Oct 2026, published 18 Sep 2026🛡️ Security

VIPER-MCP is an end-to-end automated auditing framework that combines two-pass static taint analysis (anchor queries mapping alerts to specific MCP tool handlers) with feedback-driven LLM prompt evolution to both detect and dynamically confirm taint-style vulnerabilities (command injection, SSRF, path traversal) in Model Context Protocol servers. Run against 39,884 real-world open-source MCP server repositories, it discovered 106 0-day vulnerabilities — all confirmed via end-to-end exploit traces with concrete proof-of-concept natural-language prompts — resulting in 67 assigned CVEs, including a root-privilege RCE in the bytebot computer-use agent. It reports 0% false positive rate and 7.7% false negative rate, substantially outperforming existing static and dynamic MCP security baselines.

arxiv.orgpaperAdded 22 Sep 2026, published 17 Sep 2026🛡️ Security

This arXiv paper identifies tool hallucination — LLM agents calling nonexistent tools or passing undeclared arguments — as a structural blind spot that existing tool-selection and tool-gating defenses cannot catch, since a hallucinated call was never a real gating decision. The authors propose a five-class taxonomy (H1-H5) of tool hallucination and a training-free closed-world resolver (the Resolution Rung, based on registry membership plus signature checking) that must run before any causal gate, then extend the analysis to the Model Context Protocol where merging multiple servers into one namespace creates a second hallucination class (M1-M5) from tool collisions and shadowing. Across ten hosted models they measure 322 hallucinations on single-registry tool calls and 154 on a live MCP surface, and release the versioned Hallucinated-Tools Benchmark (HTB) for comparing resolvers.

arxiv.orgpaperAdded 2 Oct 2026, published 16 Sep 2026🛡️ Security

This arXiv paper studies tool hallucination in tool-augmented LLM agents, where agents call tools that do not exist or pass arguments no schema declares, arguing existing tool-selection and tool-gating defenses structurally cannot catch it since a hallucinated call was never a decision a gate made. The authors give a five-class taxonomy (H1 to H5), propose the Resolution Rung, a training-free closed-world resolver based on registry membership plus a signature check that must run before any causal gate, and extend the analysis to the Model Context Protocol with a second taxonomy (M1 to M5) covering collisions and shadowing when multiple servers are merged into one namespace. Across ten hosted models they measure 322 hallucinations on two invocation surfaces and 154 on a live MCP surface, and release the versioned Hallucinated-Tools Benchmark for comparing resolvers.

arxiv.orgpaperAdded 2 Oct 2026, published 16 Sep 2026🧠 AI

NIST IR 8587 is a final NIST report giving federal agencies and cloud service providers implementation guidance for protecting identity tokens, access tokens, and assertions from forgery, theft, and misuse. It builds on NIST SP 800-53 (Release 5.1.1) with architectural recommendations for identity providers and authorization servers covering key management, token verification, and lifecycle controls, aimed at securing SSO, federation, and API access scenarios following recent high-profile token-forgery attacks.

csrc.nist.govpaperAdded 3 Oct 2026, published 15 Sep 2026🛡️ Security

NIST IR 8587 is a finalized interagency report, developed with CISAs Joint Cyber Defense Collaborative under Executive Order 14306, giving federal agencies and cloud service providers implementation recommendations to protect identity tokens and assertions from forgery, theft, and misuse. It builds on NIST SP 800-53 Revision 5 to detail architectural guidance for identity providers and authorization servers, plus enhancements to key management, token verification, and token lifecycle controls covering SSO, federation, API, and workload access scenarios, informed by threats seen in recent high profile token theft attacks.

csrc.nist.govpaperAdded 26 Sep 2026, published 14 Sep 2026🛡️ Security

VIPER-MCP is an automated auditing framework for Model Context Protocol servers that detects taint-style vulnerabilities in tool handlers and dynamically confirms exploitability via generated proof-of-concept prompts. It uses two-pass static analysis plus feedback-driven prompt evolution, and scanning 39,884 real-world MCP server repos found 106 0-day vulnerabilities with 67 CVE IDs assigned.

arxiv.orgpaperAdded 22 Sep 2026, published 13 Sep 2026🛡️ Security

A preregistered audit of whether identical requests to the same-named LLM API return stable outputs over time, finding they largely do not: across 52,988 audited requests, same-window repeat rankings hit Spearman 0.400 against a required 0.90, and next-day byte-identical replays hit 0.78 against a required 0.99. The authors trace the failure to label-mapping bias, candidate gaps far below the instrument's noise floor, and non-deterministic outputs for identical inputs, tested across four providers and self-hosted batch-invariant kernels, concluding a model name on shared infrastructure is not a frozen measurement instrument and that evaluations must characterize instrument noise before freezing any gate on it.

arxiv.orgpaperAdded 22 Sep 2026, published 3 Sep 2026🧠 AI