3 papers
cs.CR2026
Coverage Is Not Containment: A Fundamental Limit of Admission-Time Defenses Against Coordinated Poisoning of Vector Retrieval
Prashant Kumar Pathak, Tarun Kumar Sharma
Retrieval-augmented generation (RAG) answers a question by retrieving passages from a vector store and trusting them as context, so anyone who can add documents can try to steer th…
cs.CR2026
HaloMark: A Spectral Threshold for Embedding-Vector Watermarking under C2PA
Tarun Sharma
Foundation-model embeddings are now a primary data asset, but the content-provenance machinery built for images and audio does not transfer to them. C2PA binds to an asset with a s…
cs.CR2026
When Global Gating Is Enough: Admission-Time Hubness Control in Anisotropic Vector Retrieval Systems
Prashant Kumar Pathak, Tarun Kumar Sharma
Vector hubness, where a few points become nearest neighbors of many queries, creates a poisoning risk in retrieval-augmented generation (RAG): one injected document can influence u…