Search arXiv⌕ Search

arXiv · 2610.28067

Contextual Candour: Role-Aware Graduated Disclosure for LLMs over Mixed-Sensitivity Contexts

Abstract

LLMs increasingly operate over mixed-sensitivity contexts, where they must reason over information ranging from public to confidential while disclosing only what the user is authorised to receive. Existing approaches enforce access control as a binary decision: either fully answering or refusing, without regulating how much or what kind of information is revealed if access is granted, leading to over-refusal or unintended leakage. We introduce graduated disclosure, an access-control formulation in which the level of detail and sensitivity in a model's response is calibrated to the user's authorisation rather than treated as a grant-or-deny decision. We model graduated disclosure as a disclosure-aware generation problem and propose a reward-based optimisation framework that shapes responses toward level-appropriate abstractions while penalising unauthorised factual leakage, including paraphrases and approximations. We evaluate our approach on enterprise and clinical benchmarks and compare it with prompt-based, gating, and supervised baselines. Experiments show that our method substantially reduces information leakage while preserving correctness and utility. These results suggest that disclosure control must be integrated into the generation process itself to enable secure yet useful LLM deployments.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Devansh Srivastav, David Pape, Samira Abedini, Lea Schönherr. 2026-10-20. Contextual Candour: Role-Aware Graduated Disclosure for LLMs over Mixed-Sensitivity Contexts. https://arxiv.org/abs/2610.28067

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

AuthOr: Lower Cost Privacy-Free Garbling of Arbitrary Boolean Circuits

Privacy-free garbling schemes of Frederiksen et al. (Eurocrypt '15) are designed to satisfy only the authenticity criterion of Bellare et al. (ACM CCS '12) and to be more efficient than full-fledged garbling schemes. In this work, we improve the state-of-the-art privacy-free version of half-gates (HG) garbling of Zahur et al. (Crypto '15) by allowing an AND gate to be garbled with zero ciphertexts whenever at least one of its input wires is freely settable by the garbler. Our full solution, AuthOr, then combines the ideas from the information-theoretic garbling of Kondi and Patra (Crypto '17) with the improved HG-based scheme we obtain. AuthOr has a lower communication cost (i.e., garbled-circuit size) than HG garbling without any additional security assumptions. Theoretically, AuthOr's garbled-circuit size reduction over HG garbling ranges from 0% to 100%, with the exact improvement depending on the circuit structure. We have implemented our scheme and evaluated it on various circuits constructed by independent researchers. Our experimental results show that, in practice, the garbled-circuit size reduction can reach roughly 98%.

cs.CR↗

Sharing is caring: Attestable and Trusted Workflows out of Distrustful Components

Trusted Execution Environments (TEEs) protect private memory and attest initial code and configuration, but neither constrain nor attest shared channels between TEEs or with the untrusted host. Confidentiality thus depends on the functional correctness of all in-TEE code accessing these channels: a single misuse can leak data and compromise a pipeline. This assumption is increasingly untenable for agentic applications that generate code at runtime and cloud pipelines of mutually distrustful components. We present MICA, a confidential-computing firmware extension that decouples confidentiality from trust in in-TEE code. MICA lets tenants define, restrict, and attest channel constraints between TEEs and with the untrusted host, including transitive constraints spanning a pipeline. It extends attestation to groups of communicating TEEs, letting external parties verify the confidentiality properties induced by these constraints across a pipeline. We implement MICA on Arm CCA by extending the Realm Management Monitor with a small policy language, requiring no hardware changes and minor QEMU and KVM changes. Our evaluation demonstrates support for confidential agentic applications and pipeline computations without trusting the functional correctness of in-TEE code. MICA increases the TCB by 7% and incurs infrequent setup costs: 2-4% boot-time overhead, approximately 1.5 s for policy upload, and 246-598 ms for group attestation. Once established, Realm communication is direct, uses protected memory, and requires no MICA intervention or software encryption, yielding up to 14.5 times lower cross-TEE message latency than encrypted communication over untrusted memory.

cs.CR↗

SUDP: Secret-Use Delegation Protocol for Agentic Systems

Agentic systems now act with user secrets for APIs, messaging platforms, and cloud services. Today's agent runtimes typically implement authorization by exposure: enabling action means placing a reusable secret, or a reusable artifact derived from it, inside the runtime, so a transient prompt-injection or tool-side compromise becomes durable account compromise. Existing defenses cover adjacent pieces such as secret storage, scoped delegation, sender-constrained tokens, and runtime monitoring, but none states the combined requirement: an untrusted autonomous requester should be able to cause a user-authorized secret-backed operation without gaining reusable authority over it. We formalize this as the Agent Secret Use (ASU) problem and identify seven security properties any solution must satisfy, spanning authorization integrity and secret confidentiality. We propose the Secret-Use Delegation Protocol (SUDP), in which a requester proposes a canonical operation, the user authorizes it with a fresh authenticator-backed grant, and a custodian redeems the grant to perform the bounded use; reusable authority never crosses the requester boundary. We specialize SUDP for LLM-driven agents, where it applies whenever a tool call would exercise user-enrolled authority-bearing material. Under standard cryptographic assumptions, SUDP satisfies six of the seven properties; the seventh, runtime-memory confidentiality, is closed by composition with a hardware-rooted runtime. A reference implementation, available at https://github.com/xhyumiracle/sudp, adds sub-millisecond protocol overhead per mediated call.

cs.CR↗